@article{DrayssClausHubertetal.2019, author = {Drayß, Maria and Claus, Heike and Hubert, Kerstin and Thiel, Katrin and Berger, Anja and Sing, Andreas and van der Linden, Mark and Vogel, Ulrich and L{\^a}m, Thi{\^e}n-Tr{\´i}}, title = {Asymptomatic carriage of Neisseria meningitidis, Haemophilus influenzae, Streptococcus pneumoniae, Group A Streptococcus and Staphylococcus aureus among adults aged 65 years and older}, series = {PLoS ONE}, volume = {14}, journal = {PLoS ONE}, number = {2}, doi = {10.1371/journal.pone.0212052}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-201042}, pages = {e0212052}, year = {2019}, abstract = {Objective The aim of this study was to determine the prevalence of Neisseria meningitidis, Haemophilus influenzae, Streptococcus pneumoniae, group A Streptococcus (GAS), and Staphylococcus aureus in asymptomatic elderly people and to unravel risk factors leading to colonization. Methods A multi-centre cross-sectional study was conducted including 677 asymptomatic adults aged 65 years or more, living at home or in nursing homes. Study areas were Greater Aachen (North-Rhine-Westphalia) and Wuerzburg (Bavaria), both regions with medium to high population density. Nasal and oropharyngeal swabs as well as questionnaires were collected from October 2012 to May 2013. Statistical analysis included multiple logistic regression models. Results The carriage rate was 1.9\% ([95\%CI: 1.0-3.3\%]; 13/677) for H. influenzae, 0.3\% ([95\%CI: 0-1.1\%]; 2/677) for N. meningitidis and 0\% ([95\% CI: 0-0.5\%]; 0/677) for S. pneumoniae and GAS. Staphylococcus aureus was harboured by 28.5\% of the individuals ([95\% CI: 25.1-32.1\%]; 193/677) and 0.7\% ([95\% CI: 0.2-1.7\%]; 5/677) were positive for methicillin-resistant S. aureus. Among elderly community-dwellers colonization with S. aureus was significantly associated with higher educational level (adjusted OR: 1.905 [95\% CI: 1.248-2.908]; p = 0.003). Among nursing home residents colonization was associated with being married (adjusted OR: 3.367 [1.502-7.546]; p = 0.003). Conclusion The prevalence of N. meningitidis, H. influenzae, S. pneumoniae and GAS was low among older people in Germany. The S. aureus rate was expectedly high, while MRSA was found in less than 1\% of the individuals.}, language = {en} } @article{LuberLutzAbeleHornetal.2019, author = {Luber, Verena and Lutz, Mathias and Abele-Horn, Marianne and Einsele, Hermann and Grigoleit, G{\"o}tz Ulrich and Mielke, Stephan}, title = {Excretion of Ascaris lumbricoides following reduced-intensity allogeneic hematopoietic stem cell transplantation and consecutive treatment with mebendazole}, series = {Transplant Infectious Disease}, volume = {22}, journal = {Transplant Infectious Disease}, number = {1}, issn = {1399-3062}, doi = {10.1111/tid.13224}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-219608}, pages = {1-4}, year = {2019}, abstract = {Here, we present the unique case of a 51-year-old German patient with multiple myeloma excreting Ascaris lumbricoides in his stool five weeks after allogeneic hematopoietic stem cell transplantation. Stool analysis remained negative for the presence of eggs, and there was no eosinophilia in the peripheral blood at any time around stem cell transplantation. The patient was commenced on a three-day treatment with mebendazole, which was well tolerated. No serious interactions with the concomitant post-transplant medication or negative effects on the hematopoiesis were observed, and the myeloma still is in complete remission. To our knowledge, this is the first report on excretion of A lumbricoides in the context of allogeneic stem cell transplantation. The case is remarkable with view to the fact that the parasite has supposedly survived all courses of myeloma treatment including autologous and allogeneic conditioning. Parasitosis with A lumbricoides has a worldwide prevalence of about a billion and is extremely rare in northern Europe. Possibly the patient got infected during a trip to Egypt years before multiple myeloma was diagnosed.}, language = {en} } @article{PrausseLehnertTimmeetal.2018, author = {Prauße, Maria T. E. and Lehnert, Teresa and Timme, Sandra and H{\"u}nniger, Kerstin and Leonhardt, Ines and Kurzai, Oliver and Figge, Marc Thilo}, title = {Predictive Virtual Infection Modeling of Fungal Immune Evasion in Human Whole Blood}, series = {Frontiers in Immunology}, volume = {9}, journal = {Frontiers in Immunology}, number = {560}, issn = {1664-3224}, doi = {10.3389/fimmu.2018.00560}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-197493}, year = {2018}, abstract = {Bloodstream infections by the human-pathogenic fungi Candida albicans and Candida glabrata increasingly occur in hospitalized patients and are associated with high mortality rates. The early immune response against these fungi in human blood comprises a concerted action of humoral and cellular components of the innate immune system. Upon entering the blood, the majority of fungal cells will be eliminated by innate immune cells, i.e., neutrophils and monocytes. However, recent studies identified a population of fungal cells that can evade the immune response and thereby may disseminate and cause organ dissemination, which is frequently observed during candidemia. In this study, we investigate the so far unresolved mechanism of fungal immune evasion in human whole blood by testing hypotheses with the help of mathematical modeling. We use a previously established state-based virtual infection model for whole-blood infection with C. albicans to quantify the immune response and identified the fungal immune-evasion mechanism. While this process was assumed to be spontaneous in the previous model, we now hypothesize that the immune-evasion process is mediated by host factors and incorporate such a mechanism in the model. In particular, we propose, based on previous studies that the fungal immune-evasion mechanism could possibly arise through modification of the fungal surface by as of yet unknown proteins that are assumed to be secreted by activated neutrophils. To validate or reject any of the immune-evasion mechanisms, we compared the simulation of both immune-evasion models for different infection scenarios, i.e., infection of whole blood with either C. albicans or C. glabrata under non-neutropenic and neutropenic conditions. We found that under non-neutropenic conditions, both immune-evasion models fit the experimental data from whole-blood infection with C. albicans and C. glabrata. However, differences between the immune-evasion models could be observed for the infection outcome under neutropenic conditions with respect to the distribution of fungal cells across the immune cells. Based on these predictions, we suggested specific experimental studies that might allow for the validation or rejection of the proposed immune-evasion mechanism.}, language = {en} } @article{BecamWalterBurgertetal.2017, author = {Becam, J{\´e}r{\^o}me and Walter, Tim and Burgert, Anne and Schlegel, Jan and Sauer, Markus and Seibel, J{\"u}rgen and Schubert-Unkmeir, Alexandra}, title = {Antibacterial activity of ceramide and ceramide analogs against pathogenic Neisseria}, series = {Scientific Reports}, volume = {7}, journal = {Scientific Reports}, doi = {10.1038/s41598-017-18071-w}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-159367}, pages = {17627}, year = {2017}, abstract = {Certain fatty acids and sphingoid bases found at mucosal surfaces are known to have antibacterial activity and are thought to play a more direct role in innate immunity against bacterial infections. Herein, we analysed the antibacterial activity of sphingolipids, including the sphingoid base sphingosine as well as short-chain C\(_{6}\) and long-chain C\(_{16}\)-ceramides and azido-functionalized ceramide analogs against pathogenic Neisseriae. Determination of the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) demonstrated that short-chain ceramides and a ω-azido-functionalized C\(_{6}\)-ceramide were active against Neisseria meningitidis and N. gonorrhoeae, whereas they were inactive against Escherichia coli and Staphylococcus aureus. Kinetic assays showed that killing of N. meningitidis occurred within 2 h with ω-azido-C\(_{6}\)-ceramide at 1 X the MIC. Of note, at a bactericidal concentration, ω-azido-C\(_{6}\)-ceramide had no significant toxic effect on host cells. Moreover, lipid uptake and localization was studied by flow cytometry and confocal laser scanning microscopy (CLSM) and revealed a rapid uptake by bacteria within 5 min. CLSM and super-resolution fluorescence imaging by direct stochastic optical reconstruction microscopy demonstrated homogeneous distribution of ceramide analogs in the bacterial membrane. Taken together, these data demonstrate the potent bactericidal activity of sphingosine and synthetic short-chain ceramide analogs against pathogenic Neisseriae.}, language = {en} } @article{WagenerLoiko2017, author = {Wagener, Johannes and Loiko, Veronika}, title = {Recent insights into the paradoxical effect of echinocandins}, series = {Journal of Fungi}, volume = {4}, journal = {Journal of Fungi}, number = {1}, issn = {2309-608X}, doi = {10.3390/jof4010005}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-197960}, pages = {5}, year = {2017}, abstract = {Echinocandin antifungals represent one of the most important drug classes for the treatment of invasive fungal infections. The mode of action of the echinocandins relies on inhibition of the β-1,3-glucan synthase, an enzyme essentially required for the synthesis of the major fungal cell wall carbohydrate β-1,3-glucan. Depending on the species, echinocandins may exert fungicidal or fungistatic activity. Apparently independent of this differential activity, a surprising in vitro phenomenon called the "paradoxical effect" can be observed. The paradoxical effect is characterized by the ability of certain fungal isolates to reconstitute growth in the presence of higher echinocandin concentrations, while being fully susceptible at lower concentrations. The nature of the paradoxical effect is not fully understood and has been the focus of multiple studies in the last two decades. Here we concisely review the current literature and propose an updated model for the paradoxical effect, taking into account recent advances in the field.}, language = {en} } @article{SturmGeisselMartinetal.2020, author = {Sturm, Laura and Geißel, Bernadette and Martin, Ronny and Wagener, Johannes}, title = {Differentially Regulated Transcription Factors and ABC Transporters in a Mitochondrial Dynamics Mutant Can Alter Azole Susceptibility of Aspergillus fumigatus}, series = {Frontiers in Microbiology}, volume = {11}, journal = {Frontiers in Microbiology}, issn = {1664-302X}, doi = {10.3389/fmicb.2020.01017}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-204874}, year = {2020}, abstract = {Azole resistance of the fungal pathogen Aspergillus fumigatus is an emerging problem. To identify novel mechanisms that could mediate azole resistance in A. fumigatus, we analyzed the transcriptome of a mitochondrial fission/fusion mutant that exhibits increased azole tolerance. Approximately 12\% of the annotated genes are differentially regulated in this strain. This comprises upregulation of Cyp51A, the azole target structure, upregulation of ATP-binding cassette (ABC) superfamily and major facilitator superfamily (MFS) transporters and differential regulation of transcription factors. To study their impact on azole tolerance, conditional mutants were constructed of seven ABC transporters and 17 transcription factors. Under repressed conditions, growth rates and azole susceptibility of the mutants were similar to wild type. Under induced conditions, several transcription factor mutants showed growth phenotypes. In addition, four ABC transporter mutants and seven transcription factor mutants exhibited altered azole susceptibility. However, deletion of individual identified ABC transporters and transcription factors did not affect the increased azole tolerance of the fission/fusion mutant. Our results revealed the ability of multiple ABC transporters and transcription factors to modulate the azole susceptibility of A. fumigatus and support a model where mitochondrial dysfunctions trigger a drug resistance network that mediates azole tolerance of this mold.}, language = {en} } @article{MoremiClausMshana2016, author = {Moremi, Nyambura and Claus, Heike and Mshana, Stephen E.}, title = {Antimicrobial resistance pattern: a report of microbiological cultures at a tertiary hospital in Tanzania}, series = {BMC Infectious Diseases}, volume = {16}, journal = {BMC Infectious Diseases}, number = {756}, doi = {10.1186/s12879-016-2082-1}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-161185}, year = {2016}, abstract = {Background Antimicrobial resistance has been declared by the World Health Organization as a threat to the public health. The aim of this study was to analyze antimicrobial resistance patterns of the common pathogens occurring at the Bugando Medical Centre (BMC), Mwanza, Tanzania to provide data for antimicrobial stewardship programmes. Methods A total of 3330 microbiological culture results scripts representing non-repetitive specimens reported between June 2013 and May 2015 were retrieved and analyzed for pathogens and their susceptibility patterns using STATA-11 software. Results Out of 3330 specimens, 439 (13.2\%) had positive culture. Staphylococcus aureus (n = 100; 22.8\%), Klebsiella pneumoniae (n = 65; 14.8\%) and Escherichia coli (n = 41; 9.3\%) were the most frequently isolated bacteria. Of 78 Staphylococcus aureus tested, 27 (34.6\%) were found to be methicillin resistant Staphylococcus aureus (MRSA). Rates of resistance of Klebsiella pneumoniae and Escherichia coli isolates to third generation cephalosporins were 38.5\% (25/65) and 29.3\% (12/41) respectively. Staphylococcus aureus and Klesbiella pneumoniae were commonly isolated from bloodstream infections while Escherichia coli and Pseudomonas aeruginosa were the predominant isolates from urinary tract and wounds infections respectively. Of 23 Salmonella species isolated, 22 (95\%) were recovered from the blood. Nine of the 23 Salmonella species isolates (39\%) were found to be resistant to third generation cephalosporins. The resistance rate of gram-negative bacteria to third generation cephalosporins increased from 26.5\% in 2014 to 57.9\% in 2015 (p = 0.004) while the rate of MRSA decreased from 41.2\% in 2013 to 9.5\% in 2015 (p = 0.016). Multidrug-resistant gram-negative isolates were commonly isolated from Intensive Care Units and it was noted that, the majority of invasive infections were due to gram-negative bacteria. Conclusion There is an increase in proportion of gram-negative isolates resistant to third generation cephalosporins. The diversity of potential pathogens resistant to commonly prescribed antibiotics underscores the importance of sustained and standardized antimicrobial resistance surveillance and antibiotic stewardship programmes in developing countries.}, language = {en} } @article{GlaserSilwedelFehrholzetal.2017, author = {Glaser, Kirsten and Silwedel, Christine and Fehrholz, Markus and Waaga-Gasser, Ana M. and Henrich, Birgit and Claus, Heike and Speer, Christian P.}, title = {Ureaplasma Species Differentially Modulate Pro- and Anti-Inflammatory Cytokine Responses in Newborn and Adult Human Monocytes Pushing the State Toward Pro-Inflammation}, series = {Frontiers in Cellular and Infection Microbiology}, volume = {7}, journal = {Frontiers in Cellular and Infection Microbiology}, number = {484}, doi = {10.3389/fcimb.2017.00484}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-169958}, year = {2017}, abstract = {Background: Ureaplasma species have been associated with chorioamnionitis and preterm birth and have been implicated in the pathogenesis of neonatal short and long-term morbidity. However, being mostly commensal bacteria, controversy remains on the pro-inflammatory capacity of Ureaplasma. Discussions are ongoing on the incidence and impact of prenatal, perinatal, and postnatal infection. The present study addressed the impact of Ureaplasma isolates on monocyte-driven inflammation. Methods: Cord blood monocytes of term neonates and adult monocytes, either native or LPS-primed, were cultured with Ureaplasma urealyticum (U. urealyticum) serovar 8 (Uu8) and Ureaplasma parvum serovar 3 (Up3). Using qRT-PCR, cytokine flow cytometry, and multi-analyte immunoassay, we assessed mRNA and protein expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-8, IL-12p40, IL-10, and IL-1 receptor antagonist (IL-1ra) as well as Toll-like receptor (TLR) 2 and TLR4. Results: Uu8 and Up3 induced mRNA expression and protein release of TNF-α, IL-1β and IL-8 in term neonatal and adult monocytes (p < 0.01 and p < 0.05). Intracellular protein expression of TNF-α, IL-1β and IL-8 in Ureaplasma-stimulated cells paralleled those results. Ureaplasma-induced cytokine levels did not significantly differ from LPS-mediated levels except for lower intracellular IL-1β in adult monocytes (Uu8: p < 0.05). Remarkably, ureaplasmas did not induce IL-12p40 response and promoted lower amounts of anti-inflammatory IL-10 and IL-1ra than LPS, provoking a cytokine imbalance more in favor of pro-inflammation (IL-1β/IL-10, IL-8/IL-10 and IL-8/IL-1ra: p < 0.01, vs. LPS). In contrast to LPS, both isolates induced TLR2 mRNA in neonatal and adult cells (p < 0.001 and p < 0.05) and suppressed TLR4 mRNA in adult monocytes (p < 0.05). Upon co-stimulation, Uu8 and Up3 inhibited LPS-induced intracellular IL-1β (p < 0.001 and p < 0.05) and IL-8 in adult monocytes (p < 0.01), while LPS-induced neonatal cytokines were maintained or aggravated (p < 0.05). Conclusion: Our data demonstrate a considerable pro-inflammatory capacity of Ureaplasma isolates in human monocytes. Stimulating pro-inflammatory cytokine responses while hardly inducing immunomodulatory and anti-inflammatory cytokines, ureaplasmas might push monocyte immune responses toward pro-inflammation. Inhibition of LPS-induced cytokines in adult monocytes in contrast to sustained inflammation in term neonatal monocytes indicates a differential modulation of host immune responses to a second stimulus. Modification of TLR2 and TLR4 expression may shape host susceptibility to inflammation.}, language = {en} } @article{HeidrichBauriedlBarquistetal.2017, author = {Heidrich, Nadja and Bauriedl, Saskia and Barquist, Lars and Li, Lei and Schoen, Christoph and Vogel, J{\"o}rg}, title = {The primary transcriptome of Neisseria meningitidis and its interaction with the RNA chaperone Hfq}, series = {Nucleic Acids Research}, volume = {45}, journal = {Nucleic Acids Research}, number = {10}, doi = {10.1093/nar/gkx168}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-170828}, pages = {6147-6167}, year = {2017}, abstract = {Neisseria meningitidis is a human commensal that can also cause life-threatening meningitis and septicemia. Despite growing evidence for RNA-based regulation in meningococci, their transcriptome structure and output of regulatory small RNAs (sRNAs) are incompletely understood. Using dRNA-seq, we have mapped at single-nucleotide resolution the primary transcriptome of N. meningitidis strain 8013. Annotation of 1625 transcriptional start sites defines transcription units for most protein-coding genes but also reveals a paucity of classical σ70-type promoters, suggesting the existence of activators that compensate for the lack of -35 consensus sequences in N. meningitidis. The transcriptome maps also reveal 65 candidate sRNAs, a third of which were validated by northern blot analysis. Immunoprecipitation with the RNA chaperone Hfq drafts an unexpectedly large post-transcriptional regulatory network in this organism, comprising 23 sRNAs and hundreds of potential mRNA targets. Based on this data, using a newly developed gfp reporter system we validate an Hfq-dependent mRNA repression of the putative colonization factor PrpB by the two trans-acting sRNAs RcoF1/2. Our genome-wide RNA compendium will allow for a better understanding of meningococcal transcriptome organization and riboregulation with implications for colonization of the human nasopharynx.}, language = {en} } @article{HellenbrandClausSchinketal.2016, author = {Hellenbrand, Wiebke and Claus, Heike and Schink, Susanne and Marcus, Ulrich and Wichmann, Ole and Vogel, Ulrich}, title = {Risk of Invasive Meningococcal Disease in Men Who Have Sex with Men: Lessons Learned from an Outbreak in Germany, 2012-2013}, series = {PLoS ONE}, volume = {11}, journal = {PLoS ONE}, number = {8}, doi = {10.1371/journal.pone.0160126}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-166842}, pages = {e0160126}, year = {2016}, abstract = {Background We undertook investigations in response to an invasive meningococcal disease (IMD) outbreak in men who have sex with men (MSM) in Berlin 2012-2013 to better understand meningococcal transmission and IMD risk in MSM. Methods We retrospectively searched for further IMD cases in MSM in Germany through local health departments and undertook exploratory interviews. We performed antigen sequence typing, characterized fHbp and aniA genes of strains with the outbreak finetype and reviewed epidemiologically or spatiotemporally linked cases from 2002-2014. Results Among the 148 IMD-cases notified from 01.01.2012-30.09.2013 in 18-59 year-old men we identified 13 MSM in 6 federal states: 11 serogroup C (MenC, all finetype C:P1.5-1,10-8:F3-6), 2 MenB. Interviews with 7 MSM revealed frequent meeting of multiple partners online or via mobile apps and illicit drug use as potential risk factors. MenC incidence was 13-fold higher in MSM than non-MSM. MenC isolates from 9/11 MSM had a novel fHbp allele 766. All C:P1.5-1,10-8:F3-6 strains from MSM versus 16/23 from non-MSM had intact aniA genes (p = 0.04). Although definitive evidence for transmission among MSM in epidemiological or spatiotemporal clusters in 2002-2014 was lacking, clusters were more frequent in men aged 20-49 years. Molecular analysis of C:P1.5-1,10-8:F3-6 strains revealed cases with intact aniA since 2007, mainly associated with fHbp361, fHbp766 and fHbp813, all involving one or more MSM. Conclusions MenC incidence was elevated in MSM during the study period. Multiple casual sexual contacts and illicit drug use were common in affected MSM. In all strains from MSM we detected an intact aniA gene coding for a nitrite reductase, which permits survival in microanaerobic environments and could play a role in meningococcal transmission in MSM through urogenital colonization. Furthermore, meningococcal transmission among MSM may be sustained over large areas and thus require modified spatiotemporal scanning algorithms for timely detection and control.}, language = {en} } @article{MachataSreekantapuramHuennigeretal.2021, author = {Machata, Silke and Sreekantapuram, Sravya and H{\"u}nniger, Kerstin and Kurzai, Oliver and Dunker, Christine and Schubert, Katja and Kr{\"u}ger, Wibke and Schulze-Richter, Bianca and Speth, Cornelia and Rambach, G{\"u}nter and Jacobsen, Ilse D.}, title = {Significant Differences in Host-Pathogen Interactions Between Murine and Human Whole Blood}, series = {Frontiers in Immunology}, volume = {11}, journal = {Frontiers in Immunology}, issn = {1664-3224}, doi = {10.3389/fimmu.2020.565869}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-222575}, year = {2021}, abstract = {Murine infection models are widely used to study systemic candidiasis caused by C. albicans. Whole-blood models can help to elucidate host-pathogens interactions and have been used for several Candida species in human blood. We adapted the human whole-blood model to murine blood. Unlike human blood, murine blood was unable to reduce fungal burden and more substantial filamentation of C. albicans was observed. This coincided with less fungal association with leukocytes, especially neutrophils. The lower neutrophil number in murine blood only partially explains insufficient infection and filamentation control, as spiking with murine neutrophils had only limited effects on fungal killing. Furthermore, increased fungal survival is not mediated by enhanced filamentation, as a filament-deficient mutant was likewise not eliminated. We also observed host-dependent differences for interaction of platelets with C. albicans, showing enhanced platelet aggregation, adhesion and activation in murine blood. For human blood, opsonization was shown to decrease platelet interaction suggesting that complement factors interfere with fungus-to-platelet binding. Our results reveal substantial differences between murine and human whole-blood models infected with C. albicans and thereby demonstrate limitations in the translatability of this ex vivo model between hosts.}, language = {en} } @article{DuskeClausKroneetal.2024, author = {Duske, Helene and Claus, Heike and Krone, Manuel and L{\^a}m, Thi{\^e}n-Tr{\´i}}, title = {Prevalence of piperacillin/tazobactam resistance in invasive \(Haemophilus\) \(influenzae\) in Germany}, series = {JAC-Antimicrobial Resistance}, volume = {6}, journal = {JAC-Antimicrobial Resistance}, number = {1}, issn = {2632-1823}, doi = {10.1093/jacamr/dlad148}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-350424}, year = {2024}, abstract = {Background Haemophilus influenzae (Hi) is a Gram-negative bacterium that may cause sepsis or meningitis, treatment of which mainly includes β-lactam antibiotics. Since 2019 EUCAST breakpoints for piperacillin/tazobactam have been available. Little is known about the prevalence and mechanisms of piperacillin/tazobactam resistance in Hi. Objectives To provide reliable prevalence data for piperacillin/tazobactam resistance in Hi in Germany, to evaluate different antibiotic susceptibility testing methods and to examine possible resistance mechanisms. Methods According to EUCAST breakpoints, the MIC for piperacillin/tazobactam resistance is >0.25 mg/L. All invasive Hi in Germany from 2019 were examined by gradient agar diffusion (GAD) for piperacillin/tazobactam susceptibility. Piperacillin/tazobactam broth microdilution (BMD), piperacillin GAD on tazobactam-containing agar [piperacillin GAD on Mueller-Hinton agar with horse blood (MH-F)/tazobactam) and piperacillin/tazobactam agar dilution (AD) were used for confirmation. Phenotypic testing was complemented by ftsI sequencing. Results Piperacillin/tazobactam GAD resulted in 2.9\% (21/726) resistant Hi. BMD did not confirm piperacillin/tazobactam resistance. Two strains were found resistant by AD, of which one was also resistant using piperacillin GAD on MH-F/tazobactam. Overall, we found two strains with a piperacillin/tazobactam MIC >0.25 mg/L in at least two different tests (0.3\%). Both were β-lactamase-producing amoxicillin/clavulanate-resistant with PBP3 mutations characterized as group III-like+. Relevant PBP3 mutations occurred in six strains without phenotypic piperacillin/tazobactam resistance. These mutations suggest a reduced efficacy of β-lactam antibiotics in these isolates. Conclusions Piperacillin/tazobactam resistance prevalence in invasive Hi is low in Germany. Reduced susceptibility was correlated with PBP3 mutations, in particular with group III mutations.}, language = {en} } @phdthesis{Endres2024, author = {Endres, Leo Maximilian}, title = {Development of multicellular \(in\) \(vitro\) models of the meningeal blood-CSF barrier to study \(Neisseria\) \(meningitidis\) infection}, doi = {10.25972/OPUS-34621}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-346216}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {Neisseria meningitidis (the meningococcus) is one of the major causes of bacterial meningitis, a life-threatening inflammation of the meninges. Traversal of the meningeal blood-cerebrospinal fluid barrier (mBCSFB), which is composed of highly specialized brain endothelial cells (BECs), and subsequent interaction with leptomeningeal cells (LMCs) are critical for disease progression. Due to the human-exclusive tropism of N. meningitidis, research on this complex host-pathogen interaction is mostly limited to in vitro studies. Previous studies have primarily used peripheral or immortalized BECs alone, which do not retain relevant barrier phenotypes in culture. To study meningococcal interaction with the mBCSFB in a physiologically more accurate context, BEC-LMC co-culture models were developed in this project using BEC-like cells derived from induced pluripotent stem cells (iBECs) or hCMEC/D3 cells in combination with LMCs derived from tumor biopsies. Distinct BEC and LMC layers as well as characteristic expression of cellular markers were observed using transmission electron microscopy (TEM) and immunofluorescence staining. Clear junctional expression of brain endothelial tight and adherens junction proteins was detected in the iBEC layer. LMC co-culture increased iBEC barrier tightness and stability over a period of seven days, as determined by sodium fluorescein (NaF) permeability and transendothelial electrical resistance (TEER). Infection experiments demonstrated comparable meningococcal adhesion and invasion of the BEC layer in all models tested, consistent with previously published data. While only few bacteria crossed the iBEC-LMC barrier initially, transmigration rates increased substantially over 24 hours, despite constant high TEER. After 24 hours of infection, deterioration of the barrier properties was observed including loss of TEER and altered expression of tight and adherens junction components. Reduced mRNA levels of ZO-1, claudin-5, and VE-cadherin were detected in BECs from all models. qPCR and siRNA knockdown data suggested that transcriptional downregulation of these genes was potentially but not solely mediated by Snail1. Immunofluorescence staining showed reduced junctional coverage of occludin, indicating N. meningitidis-induced post-transcriptional modulation of this protein, as previous studies have suggested. Together, these results suggest a potential combination of transcellular and paracellular meningococcal traversal of the mBCSFB, with the more accessible paracellular route becoming available upon barrier disruption after prolonged N. meningitidis infection. Finally, N. meningitidis induced cellular expression of pro-inflammatory cytokines and chemokines such as IL-8 in all mBCSFB models. Overall, the work described in this thesis highlights the usefulness of advanced in vitro models of the mBCSFB that mimic native physiology and exhibit relevant barrier properties to study infection with meningeal pathogens such as N. meningitidis.}, subject = {Bakterielle Hirnhautentz{\"u}ndung}, language = {en} } @article{DichtlKocForsteretal.2021, author = {Dichtl, Karl and Koc, {\"O}zlem and Forster, Johannes and Scharf, Christina and Suerbaum, Sebastian and Andrassy, Joachim and Wagener, Johannes and Schroeder, Ines}, title = {An invasive infection caused by the thermophilic mold Talaromyces thermophilus}, series = {Infection}, volume = {49}, journal = {Infection}, number = {6}, issn = {0300-8126}, doi = {10.1007/s15010-021-01648-z}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-308970}, pages = {1347-1353}, year = {2021}, abstract = {Background Increasing incidence of invasive infections caused by rare fungi was observed over the recent years. Case Here, we describe the first reported case of an infection caused by the thermophilic mold Talaromyces thermophilus. Cultivation and, hence, identification of this fastidious organism is challenging since standard incubation conditions are not sufficient. Retrospective analysis of patient samples and in vitro experiments demonstrated that testing for fungal antigens, i.e., the cell wall components galactomannan and β-1,3-D-glucan, is a promising tool.}, language = {en} } @phdthesis{Ulrich2024, author = {Ulrich, Johannes}, title = {Molekulare Charaktierisierung einer DyP-Typ Peroxidase des Humanparasiten \(Echinococcus\) \(multilocularis\)}, doi = {10.25972/OPUS-35714}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-357143}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {Die Alveol{\"a}re Echinokokkose (AE) ist eine t{\"o}dliche Infektionserkrankung, die durch den parasit{\"a}ren Plattwurm Echinococcus multilocularis verursacht wird. Genomanalysen von E. multilocularis ergaben ein Gen, das laut Vorhersage f{\"u}r eine DyP-Typ Peroxidase codiere. Ziel dieser Arbeit ist die biologische Funktion des codierten Enzyms besser zu verstehen und Hinweise auf eine m{\"o}gliche Rolle in der Abwehr von Reaktiven Sauerstoffspezies (ROS) zu erlangen. Das Gen wurde heterolog in E. Coli exprimiert und molekulare Charakteristika des Gens mit bioinformatischen und molekularbiologischen Methoden untersucht. Quantitative RT-PCR Untersuchungen gaben Aufschluss {\"u}ber das Transkriptprofil von emipox in unterschiedlichen Entwicklungsstadien von E. mulitlocularis. Mittels Whole-Mount In Situ-Hybridisierung (WMISH) wurden die Transkripte zudem lokalisiert und ihre Beziehung zum Stammzellsystem von E. multilocularis n{\"a}her untersucht. Die Zugeh{\"o}rigkeit von EmIPOX zur Gruppe der DyP-Typ Peroxidasen wurde best{\"a}tigt. Homologe beim Menschen kommen nicht vor. Es konnte nachgewiesen werden, dass Transkripte von emipox auch, aber keinesfalls ausschließlich, in Stammzellen vorliegen. {\"U}berdurchschnittlich viele Transkripte liegen im aktivierten Protoscolex und im Metacestoden ex vivo aus einer infizierten Wirtsleber vor. Untersuchungen zur Enzymaktivit{\"a}t von EmIPOX zeigten neben einer Peroxidase- auch eine Katalaseaktivit{\"a}t. Die vorliegende Arbeit ist die erste Charakterisierung einer DyP-Typ Peroxidase bei Tieren. Sie legt nahe, dass EmIPOX eine Rolle in der Entgiftung von ROS in E. multilocularis spielt und stellt den Charakter von EmIPOX als potenzieller pharmakologischer Zielstruktur heraus.}, subject = {Fuchsbandwurm}, language = {de} } @article{SchlesingerWeissbrichWedekinketal.2020, author = {Schlesinger, Tobias and Weißbrich, Benedikt and Wedekink, Florian and Notz, Quirin and Herrmann, Johannes and Krone, Manuel and Sitter, Magdalena and Schmid, Benedikt and Kredel, Markus and Stumpner, Jan and D{\"o}lken, Lars and Wischhusen, J{\"o}rg and Kranke, Peter and Meybohm, Patrick and Lotz, Christpher}, title = {Biodistribution and serologic response in SARS-CoV-2 induced ARDS: A cohort study}, series = {PLoS One}, volume = {15, 2020}, journal = {PLoS One}, number = {11}, doi = {10.1371/journal.pone.0242917}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-231348}, year = {2020}, abstract = {Background The viral load and tissue distribution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remain important questions. The current study investigated SARS-CoV-2 viral load, biodistribution and anti-SARS-CoV-2 antibody formation in patients suffering from severe corona virus disease 2019 (COVID-19) induced acute respiratory distress syndrome (ARDS). Methods This is a retrospective single-center study in 23 patients with COVID-19-induced ARDS. Data were collected within routine intensive care. SARS-CoV-2 viral load was assessed via reverse transcription quantitative polymerase chain reaction (RT-qPCR). Overall, 478 virology samples were taken. Anti-SARS-CoV-2-Spike-receptor binding domain (RBD) antibody detection of blood samples was performed with an enzyme-linked immunosorbent assay. Results Most patients (91\%) suffered from severe ARDS during ICU treatment with a 30-day mortality of 30\%. None of the patients received antiviral treatment. Tracheal aspirates tested positive for SARS-CoV-2 in 100\% of the cases, oropharyngeal swabs only in 77\%. Blood samples were positive in 26\% of the patients. No difference of viral load was found in tracheal or blood samples with regard to 30-day survival or disease severity. SARS-CoV-2 was never found in dialysate. Serologic testing revealed significantly lower concentrations of SARS-CoV-2 neutralizing IgM and IgA antibodies in survivors compared to non-survivors (p = 0.009). Conclusions COVID-19 induced ARDS is accompanied by a high viral load of SARS-CoV-2 in tracheal aspirates, which remained detectable in the majority throughout intensive care treatment. Remarkably, SARS-CoV-2 RNA was never detected in dialysate even in patients with RNAemia. Viral load or the buildup of neutralizing antibodies was not associated with 30-day survival or disease severity.}, language = {en} } @article{FlemmingHankirErnestusetal.2020, author = {Flemming, S. and Hankir, M. and Ernestus, R.-I. and Seyfried, F. and Germer, C.-T. and Meybohm, P. and Wurmb, T. and Vogel, U. and Wiegering, A.}, title = {Surgery in times of COVID-19 — recommendations for hospital and patient management}, series = {Langenbeck's Archives of Surgery}, volume = {405}, journal = {Langenbeck's Archives of Surgery}, issn = {1435-2443}, doi = {10.1007/s00423-020-01888-x}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-231766}, pages = {359-364}, year = {2020}, abstract = {Background The novel coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2), has escalated rapidly to a global pandemic stretching healthcare systems worldwide to their limits. Surgeonshave had to immediately react to this unprecedented clinical challenge by systematically repurposing surgical wards. Purpose To provide a detailed set of guidelines developed in a surgical ward at University Hospital Wuerzburg to safelyaccommodate the exponentially rising cases of SARS-CoV-2 infected patients without compromising the care of emergencysurgery and oncological patients or jeopardizing the well-being of hospital staff. Conclusions The dynamic prioritization of SARS-CoV-2 infected and surgical patient groups is key to preserving life whilemaintaining high surgical standards. Strictly segregating patient groups in emergency rooms, non-intensive care wards andoperating areas prevents viral spread while adequately training and carefully selecting hospital staff allow them to confidentlyand successfully undertake their respective clinical duties.}, language = {en} } @article{BeierleSchobelVogeletal.2021, author = {Beierle, Felix and Schobel, Johannes and Vogel, Carsten and Allgaier, Johannes and Mulansky, Lena and Haug, Fabian and Haug, Julian and Schlee, Winfried and Holfelder, Marc and Stach, Michael and Schickler, Marc and Baumeister, Harald and Cohrdes, Caroline and Deckert, J{\"u}rgen and Deserno, Lorenz and Edler, Johanna-Sophie and Eichner, Felizitas A. and Greger, Helmut and Hein, Grit and Heuschmann, Peter and John, Dennis and Kestler, Hans A. and Krefting, Dagmar and Langguth, Berthold and Meybohm, Patrick and Probst, Thomas and Reichert, Manfred and Romanos, Marcel and St{\"o}rk, Stefan and Terhorst, Yannik and Weiß, Martin and Pryss, R{\"u}diger}, title = {Corona Health — A Study- and Sensor-Based Mobile App Platform Exploring Aspects of the COVID-19 Pandemic}, series = {International Journal of Environmental Research and Public Health}, volume = {18}, journal = {International Journal of Environmental Research and Public Health}, number = {14}, issn = {1660-4601}, doi = {10.3390/ijerph18147395}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-242658}, year = {2021}, abstract = {Physical and mental well-being during the COVID-19 pandemic is typically assessed via surveys, which might make it difficult to conduct longitudinal studies and might lead to data suffering from recall bias. Ecological momentary assessment (EMA) driven smartphone apps can help alleviate such issues, allowing for in situ recordings. Implementing such an app is not trivial, necessitates strict regulatory and legal requirements, and requires short development cycles to appropriately react to abrupt changes in the pandemic. Based on an existing app framework, we developed Corona Health, an app that serves as a platform for deploying questionnaire-based studies in combination with recordings of mobile sensors. In this paper, we present the technical details of Corona Health and provide first insights into the collected data. Through collaborative efforts from experts from public health, medicine, psychology, and computer science, we released Corona Health publicly on Google Play and the Apple App Store (in July 2020) in eight languages and attracted 7290 installations so far. Currently, five studies related to physical and mental well-being are deployed and 17,241 questionnaires have been filled out. Corona Health proves to be a viable tool for conducting research related to the COVID-19 pandemic and can serve as a blueprint for future EMA-based studies. The data we collected will substantially improve our knowledge on mental and physical health states, traits and trajectories as well as its risk and protective factors over the course of the COVID-19 pandemic and its diverse prevention measures.}, language = {en} } @article{CucherMaricontiManciullietal.2023, author = {Cucher, Marcela A. and Mariconti, Mara and Manciulli, Tommaso and Vola, Ambra and Rosenzvit, Mara C. and Brehm, Klaus and Kamenetzky, Laura and Brunetti, Enrico}, title = {Circulating small RNA profiling of patients with alveolar and cystic echinococcosis}, series = {Biology}, volume = {12}, journal = {Biology}, number = {5}, issn = {2079-7737}, doi = {10.3390/biology12050715}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-319270}, year = {2023}, abstract = {Alveolar (AE) and cystic (CE) echinococcosis are two parasitic diseases caused by the tapeworms Echinococcus multilocularis and E. granulosus sensu lato (s. l.), respectively. Currently, AE and CE are mainly diagnosed by means of imaging techniques, serology, and clinical and epidemiological data. However, no viability markers that indicate parasite state during infection are available. Extracellular small RNAs (sRNAs) are short non-coding RNAs that can be secreted by cells through association with extracellular vesicles, proteins, or lipoproteins. Circulating sRNAs can show altered expression in pathological states; hence, they are intensively studied as biomarkers for several diseases. Here, we profiled the sRNA transcriptomes of AE and CE patients to identify novel biomarkers to aid in medical decisions when current diagnostic procedures are inconclusive. For this, endogenous and parasitic sRNAs were analyzed by sRNA sequencing in serum from disease negative, positive, and treated patients and patients harboring a non-parasitic lesion. Consequently, 20 differentially expressed sRNAs associated with AE, CE, and/or non-parasitic lesion were identified. Our results represent an in-depth characterization of the effect E. multilocularis and E. granulosus s. l. exert on the extracellular sRNA landscape in human infections and provide a set of novel candidate biomarkers for both AE and CE detection.}, language = {en} } @article{WeissGruendahlDeckertetal.2023, author = {Weiß, Martin and Gr{\"u}ndahl, Marthe and Deckert, J{\"u}rgen and Eichner, Felizitas A. and Kohls, Mirjam and St{\"o}rk, Stefan and Heuschmann, Peter U. and Hein, Grit}, title = {Differential network interactions between psychosocial factors, mental health, and health-related quality of life in women and men}, series = {Scientific Reports}, volume = {13}, journal = {Scientific Reports}, organization = {STAAB-COVID Study Group}, doi = {10.1038/s41598-023-38525-8}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-357858}, year = {2023}, abstract = {Psychosocial factors affect mental health and health-related quality of life (HRQL) in a complex manner, yet gender differences in these interactions remain poorly understood. We investigated whether psychosocial factors such as social support and personal and work-related concerns impact mental health and HRQL differentially in women and men during the first year of the COVID-19 pandemic. Between June and October 2020, the first part of a COVID-19-specific program was conducted within the "Characteristics and Course of Heart Failure Stages A-B and Determinants of Progression (STAAB)" cohort study, a representative age- and gender-stratified sample of the general population of W{\"u}rzburg, Germany. Using psychometric networks, we first established the complex relations between personal social support, personal and work-related concerns, and their interactions with anxiety, depression, and HRQL. Second, we tested for gender differences by comparing expected influence, edge weight differences, and stability of the networks. The network comparison revealed a significant difference in the overall network structure. The male (N = 1370) but not the female network (N = 1520) showed a positive link between work-related concern and anxiety. In both networks, anxiety was the most central variable. These findings provide further evidence that the complex interplay of psychosocial factors with mental health and HRQL decisively depends on gender. Our results are relevant for the development of gender-specific interventions to increase resilience in times of pandemic crisis.}, language = {en} } @article{HaederSchaeubleGehlenetal.2023, author = {H{\"a}der, Antje and Sch{\"a}uble, Sascha and Gehlen, Jan and Thielemann, Nadja and Buerfent, Benedikt C. and Sch{\"u}ller, Vitalia and Hess, Timo and Wolf, Thomas and Schr{\"o}der, Julia and Weber, Michael and H{\"u}nniger, Kerstin and L{\"o}ffler, J{\"u}rgen and Vylkova, Slavena and Panagiotou, Gianni and Schumacher, Johannes and Kurzai, Oliver}, title = {Pathogen-specific innate immune response patterns are distinctly affected by genetic diversity}, series = {Nature Communications}, volume = {14}, journal = {Nature Communications}, doi = {10.1038/s41467-023-38994-5}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-357441}, year = {2023}, abstract = {Innate immune responses vary by pathogen and host genetics. We analyze quantitative trait loci (eQTLs) and transcriptomes of monocytes from 215 individuals stimulated by fungal, Gram-negative or Gram-positive bacterial pathogens. We identify conserved monocyte responses to bacterial pathogens and a distinct antifungal response. These include 745 response eQTLs (reQTLs) and corresponding genes with pathogen-specific effects, which we find first in samples of male donors and subsequently confirm for selected reQTLs in females. reQTLs affect predominantly upregulated genes that regulate immune response via e.g., NOD-like, C-type lectin, Toll-like and complement receptor-signaling pathways. Hence, reQTLs provide a functional explanation for individual differences in innate response patterns. Our identified reQTLs are also associated with cancer, autoimmunity, inflammatory and infectious diseases as shown by external genome-wide association studies. Thus, reQTLs help to explain interindividual variation in immune response to infection and provide candidate genes for variants associated with a range of diseases.}, language = {en} } @article{SchreiberLohrBaltesetal.2023, author = {Schreiber, Laura M. and Lohr, David and Baltes, Steffen and Vogel, Ulrich and Elabyad, Ibrahim A. and Bille, Maya and Reiter, Theresa and Kosmala, Aleksander and Gassenmaier, Tobias and Stefanescu, Maria R. and Kollmann, Alena and Aures, Julia and Schnitter, Florian and Pali, Mihaela and Ueda, Yuichiro and Williams, Tatiana and Christa, Martin and Hofmann, Ulrich and Bauer, Wolfgang and Gerull, Brenda and Zernecke, Alma and Erg{\"u}n, S{\"u}leyman and Terekhov, Maxim}, title = {Ultra-high field cardiac MRI in large animals and humans for translational cardiovascular research}, series = {Frontiers in Cardiovascular Medicine}, volume = {10}, journal = {Frontiers in Cardiovascular Medicine}, issn = {2297-055X}, doi = {10.3389/fcvm.2023.1068390}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-317398}, year = {2023}, abstract = {A key step in translational cardiovascular research is the use of large animal models to better understand normal and abnormal physiology, to test drugs or interventions, or to perform studies which would be considered unethical in human subjects. Ultrahigh field magnetic resonance imaging (UHF-MRI) at 7 T field strength is becoming increasingly available for imaging of the heart and, when compared to clinically established field strengths, promises better image quality and image information content, more precise functional analysis, potentially new image contrasts, and as all in-vivo imaging techniques, a reduction of the number of animals per study because of the possibility to scan every animal repeatedly. We present here a solution to the dual use problem of whole-body UHF-MRI systems, which are typically installed in clinical environments, to both UHF-MRI in large animals and humans. Moreover, we provide evidence that in such a research infrastructure UHF-MRI, and ideally combined with a standard small-bore UHF-MRI system, can contribute to a variety of spatial scales in translational cardiovascular research: from cardiac organoids, Zebra fish and rodent hearts to large animal models such as pigs and humans. We present pilot data from serial CINE, late gadolinium enhancement, and susceptibility weighted UHF-MRI in a myocardial infarction model over eight weeks. In 14 pigs which were delivered from a breeding facility in a national SARS-CoV-2 hotspot, we found no infection in the incoming pigs. Human scanning using CINE and phase contrast flow measurements provided good image quality of the left and right ventricle. Agreement of functional analysis between CINE and phase contrast MRI was excellent. MRI in arrested hearts or excised vascular tissue for MRI-based histologic imaging, structural imaging of myofiber and vascular smooth muscle cell architecture using high-resolution diffusion tensor imaging, and UHF-MRI for monitoring free radicals as a surrogate for MRI of reactive oxygen species in studies of oxidative stress are demonstrated. We conclude that UHF-MRI has the potential to become an important precision imaging modality in translational cardiovascular research.}, language = {en} } @article{SilwedelSpeerHaarmannetal.2019, author = {Silwedel, Christine and Speer, Christian P. and Haarmann, Axel and Fehrholz, Markus and Claus, Heike and Schlegel, Nicolas and Glaser, Kirsten}, title = {Ureaplasma species modulate cytokine and chemokine responses in human brain microvascular endothelial cells}, series = {International Journal of Molecular Science}, volume = {20}, journal = {International Journal of Molecular Science}, number = {14}, issn = {1422-0067}, doi = {10.3390/ijms20143583}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-201848}, year = {2019}, abstract = {Ureaplasma species are common colonizers of the adult genitourinary tract and often considered as low-virulence commensals. Intraamniotic Ureaplasma infections, however, facilitate chorioamnionitis and preterm birth, and cases of Ureaplasma-induced neonatal sepsis, pneumonia, and meningitis raise a growing awareness of their clinical relevance. In vitro studies are scarce but demonstrate distinct Ureaplasma-driven impacts on immune mechanisms. The current study addressed cytokine and chemokine responses upon exposure of native or lipopolysaccharide (LPS) co-stimulated human brain microvascular endothelial cells (HBMEC) to Ureaplasma urealyticum or U. parvum, using qRT-PCR, RNA sequencing, multi-analyte immunoassay, and flow cytometry. Ureaplasma exposure in native HBMEC reduced monocyte chemoattractant protein (MCP)-3 mRNA expression (p < 0.01, vs. broth). In co-stimulated HBMEC, Ureaplasma spp. attenuated LPS-evoked mRNA responses for C-X-C chemokine ligand 5, MCP-1, and MCP-3 (p < 0.05, vs. LPS) and mitigated LPS-driven interleukin (IL)-1α protein secretion, as well as IL-8 mRNA and protein responses (p < 0.05). Furthermore, Ureaplasma isolates increased C-X-C chemokine receptor 4 mRNA levels in native and LPS co-stimulated HBMEC (p < 0.05). The presented results may imply immunomodulatory capacities of Ureaplasma spp. which may ultimately promote chronic colonization and long-term neuroinflammation.}, language = {en} } @article{KruegerLeskienSchulleretal.2021, author = {Kr{\"u}ger, S{\"o}ren and Leskien, Miriam and Schuller, Patricia and Prifert, Christiane and Weißbrich, Benedikt and Vogel, Ulrich and Krone, Manuel}, title = {Performance and feasibility of universal PCR admission screening for SARS-CoV-2 in a German tertiary care hospital}, series = {Journal of Medical Virology}, volume = {93}, journal = {Journal of Medical Virology}, number = {5}, doi = {10.1002/jmv.26770}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-238971}, pages = {2890 -- 2898}, year = {2021}, abstract = {Anamnestic screening of symptoms and contact history is applied to identify coronavirus disease 2019 (COVID-19) patients on admission. However, asymptomatic and presymptomatic patients remain undetected although the viral load may be high. In this retrospective cohort study, all hospitalized patients who received polymerase chain reaction (PCR) admission testing from March 26th until May 24th, 2020 were included. Data on COVID-19-specific symptoms and contact history to COVID-19 cases were retrospectively extracted from patient files and from contact tracing notes. The compliance to the universal testing protocol was high with 90\%. Out of 6940 tested patients, 27 new severe acute respiratory syndrome coronavirus-2 infections (0.4\%) were detected. Seven of those COVID-19 cases (26\% of all new cases) were asymptomatic and had no positive contact history, but were identified through a positive PCR test. The number needed to identify an asymptomatic patient was 425 in the first wave of the epidemic, 1218 in the low incidence phase. The specificity of the method was above 99.9\%. Universal PCR testing was highly accepted by staff as demonstrated by high compliance. The costs to detect one asymptomatic case in future studies need to be traded off against the costs and damage caused by potential outbreaks of COVID-19.}, language = {en} } @article{SpringerHeldMengolietal.2021, author = {Springer, Jan and Held, J{\"u}rgen and Mengoli, Carlo and Schlegel, Paul Gerhardt and Gamon, Florian and Tr{\"a}ger, Johannes and Kurzai, Oliver and Einsele, Hermann and Loeffler, Juergen and Eyrich, Matthias}, title = {Diagnostic performance of (1→3)-β-D-glucan alone and in combination with aspergillus PCR and galactomannan in serum of pediatric patients after allogeneic hematopoietic stem cell transplantation}, series = {Journal of Fungi}, volume = {7}, journal = {Journal of Fungi}, number = {3}, issn = {2309-608X}, doi = {10.3390/jof7030238}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-234179}, year = {2021}, abstract = {Data on biomarker-assisted diagnosis of invasive aspergillosis (IA) in pediatric patients is scarce. Therefore, we conducted a cohort study over two years including 404 serum specimens of 26 pediatric patients after allogeneic hematopoietic stem cell transplantation (alloSCT). Sera were tested prospectively twice weekly for Aspergillus-specific DNA, galactomannan (GM), and retrospectively for (1→3)-β-D-glucan (BDG). Three probable IA and two possible invasive fungal disease (IFD) cases were identified using the European Organization for Research and Treatment of Cancer and the Mycoses Study Group (EORTC/MSGERC) 2019 consensus definitions. Sensitivity and specificity for diagnosis of probable IA and possible IFD was 80\% (95\% confidential interval (CI): 28-99\%) and 55\% (95\% CI: 32-77\%) for BDG, 40\% (95\% CI: 5-85\%) and 100\% (95\% CI: 83-100\%) for GM, and 60\% (95\% CI: 15-95\%) and 95\% (95\% CI: 75-100\%) for Aspergillus-specific real-time PCR. However, sensitivities have to be interpreted with great caution due to the limited number of IA cases. Interestingly, the low specificity of BDG was largely caused by false-positive BDG results that clustered around the date of alloSCT. The following strategies were able to increase BDG specificity: two consecutive positive BDG tests for diagnosis (specificity 80\% (95\% CI: 56-94\%)); using an optimized cutoff value of 306 pg/mL (specificity 90\% (95\% CI: 68-99\%)) and testing BDG only after the acute posttransplant phase. In summary, BDG can help to diagnose IA in pediatric alloSCT recipients. However, due to the poor specificity either an increased cutoff value should be utilized or BDG results should be confirmed by an alternative Aspergillus assay.}, language = {en} } @article{MottolaRamirezZavalaHuenningeretal.2021, author = {Mottola, Austin and Ram{\´i}rez-Zavala, Bernardo and H{\"u}nninger, Kerstin and Kurzai, Oliver and Morschh{\"a}user, Joachim}, title = {The zinc cluster transcription factor Czf1 regulates cell wall architecture and integrity in Candida albicans}, series = {Molecular Microbiology}, volume = {116}, journal = {Molecular Microbiology}, number = {2}, doi = {10.1111/mmi.14727}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-259583}, pages = {483-497}, year = {2021}, abstract = {The fungal cell wall is essential for the maintenance of cellular integrity and mediates interactions of the cells with the environment. It is a highly flexible organelle whose composition and organization is modulated in response to changing growth conditions. In the pathogenic yeast Candida albicans, a network of signaling pathways regulates the structure of the cell wall, and mutants with defects in these pathways are hypersensitive to cell wall stress. By harnessing a library of genetically activated forms of all C. albicans zinc cluster transcription factors, we found that a hyperactive Czf1 rescued the hypersensitivity to cell wall stress of different protein kinase deletion mutants. The hyperactive Czf1 induced the expression of many genes with cell wall-related functions and caused visible changes in the cell wall structure. C. albicans czf1Δ mutants were hypersensitive to the antifungal drug caspofungin, which inhibits cell wall biosynthesis. The changes in cell wall architecture caused by hyperactivity or absence of Czf1 resulted in an increased recognition of C. albicans by human neutrophils. Our results show that Czf1, which is known as a regulator of filamentous growth and white-opaque switching, controls the expression of cell wall genes and modulates the architecture of the cell wall.}, language = {en} } @article{DickKraussHillenkampetal.2017, author = {Dick, Julia and Krauß, Patrizia and Hillenkamp, Jost and Kohlmorgen, Britta and Schoen, Christoph}, title = {Postoperative Tropheryma whipplei endophthalmitis - a case report highlighting the additive value of molecular testing}, series = {JMM Case Reports}, volume = {4}, journal = {JMM Case Reports}, doi = {10.1099/jmmcr.0.005124}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-158823}, pages = {e005124}, year = {2017}, abstract = {Introduction. Tropheryma whipplei is the causative agent of Whipple's disease. Gastrointestinal and lymphatic tissues are affected in the majority of cases, resulting in diarrhoea, malabsorption and fever. Here, we report a rare case of ocular manifestation in a patient lacking the typical Whipple symptoms. Case presentation. A 74-year-old Caucasian female presented with blurred vision in the right eye over a period of 1-2 months, accompanied by stinging pain and conjunctival hyperaemia for the last 2 days. Upon admission, visual acuity was hand motion in the affected eye. Ophthalmological examination showed typical signs of intraocular inflammation. Diagnostic and therapeutic pars plana vitrectomy including vitreous biopsy and intravitreal instillation of vancomycin and amikacin was performed within hours of initial presentation. Both microscopic analysis and microbial cultures of the vitreous biopsy remained negative for bacteria and fungi. The postoperative antibiotic regime included intravenous administration of ceftriaxone in combination with topical tobramycin and ofloxacin. Due to the empirical therapy the inflammation ceased and the patient was discharged after 5 days with cefpodoxime orally and local antibiotic and steroidal therapy. Meanwhile, the vitreous body had undergone testing by PCR for the eubacterial 16S rRNA gene, which was found to be positive. Analysis of the PCR product revealed a specific sequence of T. whipplei. Conclusion. In our patient, endophthalmitis was the first and only symptom of Morbus Whipple, while most patients with Whipple's disease suffer from severe gastrointestinal symptoms. 16S rDNA PCR should be considered for any intraocular infection when microscopy and standard culture methods remain negative.}, language = {en} } @article{TappeLauruschkatStrobeletal.2022, author = {Tappe, Beeke and Lauruschkat, Chris D. and Strobel, Lea and Pantale{\´o}n Garc{\´i}a, Jezreel and Kurzai, Oliver and Rebhan, Silke and Kraus, Sabrina and Pfeuffer-Jovic, Elena and Bussemer, Lydia and Possler, Lotte and Held, Matthias and H{\"u}nniger, Kerstin and Kniemeyer, Olaf and Sch{\"a}uble, Sascha and Brakhage, Axel A. and Panagiotou, Gianni and White, P. Lewis and Einsele, Hermann and L{\"o}ffler, J{\"u}rgen and Wurster, Sebastian}, title = {COVID-19 patients share common, corticosteroid-independent features of impaired host immunity to pathogenic molds}, series = {Frontiers in Immunology}, volume = {13}, journal = {Frontiers in Immunology}, issn = {1664-3224}, doi = {10.3389/fimmu.2022.954985}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-283558}, year = {2022}, abstract = {Patients suffering from coronavirus disease-2019 (COVID-19) are susceptible to deadly secondary fungal infections such as COVID-19-associated pulmonary aspergillosis and COVID-19-associated mucormycosis. Despite this clinical observation, direct experimental evidence for severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2)-driven alterations of antifungal immunity is scarce. Using an ex-vivo whole blood stimulation assay, we challenged blood from twelve COVID-19 patients with Aspergillus fumigatus and Rhizopus arrhizus antigens and studied the expression of activation, maturation, and exhaustion markers, as well as cytokine secretion. Compared to healthy controls, T-helper cells from COVID-19 patients displayed increased expression levels of the exhaustion marker PD-1 and weakened A. fumigatus- and R. arrhizus-induced activation. While baseline secretion of proinflammatory cytokines was massively elevated, whole blood from COVID-19 patients elicited diminished release of T-cellular (e.g., IFN-γ, IL-2) and innate immune cell-derived (e.g., CXCL9, CXCL10) cytokines in response to A. fumigatus and R. arrhizus antigens. Additionally, samples from COVID-19 patients showed deficient granulocyte activation by mold antigens and reduced fungal killing capacity of neutrophils. These features of weakened anti-mold immune responses were largely decoupled from COVID-19 severity, the time elapsed since diagnosis of COVID-19, and recent corticosteroid uptake, suggesting that impaired anti-mold defense is a common denominator of the underlying SARS-CoV-2 infection. Taken together, these results expand our understanding of the immune predisposition to post-viral mold infections and could inform future studies of immunotherapeutic strategies to prevent and treat fungal superinfections in COVID-19 patients.}, language = {en} } @article{SpringerWaltherRickertsetal.2019, author = {Springer, Jan and Walther, Grit and Rickerts, Volker and Hamprecht, Axel and Willinger, Birgit and Teschner, Daniel and Einsele, Hermann and Kurzai, Oliver and Loeffler, Juergen}, title = {Detection of Fusarium Species in Clinical Specimens by Probe-Based Real-Time PCR}, series = {Journal of Fungi}, volume = {5}, journal = {Journal of Fungi}, number = {4}, issn = {2309-608X}, doi = {10.3390/jof5040105}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-193111}, pages = {105}, year = {2019}, abstract = {The mold Fusarium is a ubiquitous fungus causing plant, animal and human infections. In humans, Fusarium spp. are the major cause of eye infections in patients wearing contact lenses or after local trauma. Systemic infections by Fusarium spp. mainly occur in immunosuppressed patients and can disseminate throughout the human body. Due to high levels of resistance to antifungals a fast identification of the causative agent is an urgent need. By using a probe-based real-time PCR assay specific for the genus Fusarium we analysed several different clinical specimens detecting Fusarium spp. commonly found in clinical samples in Germany. Also, a large collection of lung fluid samples of haematological patients was analysed (n = 243). In these, two samples (0.8\%) were reproducibly positive, but only one could be confirmed by sequencing. For this case of probable invasive fungal disease (IFD) culture was positive for Fusarium species. Here we describe a rapid, probe-based real-time PCR assay to specifically detect DNA from a broad range of Fusarium species and its application to clinically relevant specimens.}, language = {en} } @article{MoremiClausVogeletal.2017, author = {Moremi, Nyambura and Claus, Heike and Vogel, Ulrich and Mshana, Stephen E.}, title = {Faecal carriage of CTX-M extended-spectrum beta-lactamase-producing Enterobacteriaceae among street children dwelling in Mwanza city, Tanzania}, series = {PLoS ONE}, volume = {12}, journal = {PLoS ONE}, number = {9}, doi = {10.1371/journal.pone.0184592}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-170331}, pages = {e0184592}, year = {2017}, abstract = {Background Data on ESBL carriage of healthy people including children are scarce especially in developing countries. We analyzed the prevalence and genotypes of ESBL-producing Enterobacteriaceae (EPE) in Tanzanian street children with rare contact to healthcare facilities but significant interactions with the environment, animals and other people. Methodology/ Principle findings Between April and July 2015, stool samples of 107 street children, who live in urban Mwanza were analyzed for EPE. Intestinal carriage of EPE was found in 34 (31.8\%, 95\% CI; 22.7-40.3) children. Of the 36 isolates from 34 children, 30 (83.3\%) were Escherichia coli (E. coli) and six Klebsiella pneumoniae (K. pneumoniae). Out of 36 isolates, 36 (100\%), 35 (97\%), 25 (69\%) and 16 (44\%) were resistant to tetracycline, trimethoprim-sulfamethoxazole, ciprofloxacin and gentamicin, respectively. Beta-lactamase genes and the multilocus sequence types of E. coli and K. pneumoniae were characterized. ESBL gene bla\(_{CTX-M-15}\) was detected in 75\% (27/36) of ESBL isolates. Sequence types (STs) 131, 10, 448 and 617 were the most prevalent in E. coli. Use of local herbs (OR: 3.5, 95\% CI: 1.51-8.08, P = 0.003) and spending day and night on streets (OR: 3.6, 95\% CI: 1.44-8.97, P = 0.005) were independent predictors of ESBL carriage. Conclusions/ Significance We observed a high prevalence of bla\(_{CTX-M-15}\) in EPE collected from street children in Tanzania. Detection of E. coli STs 131, 10, 38 and 648, which have been observed worldwide in animals and people, highlights the need for multidisciplinary approaches to understand the epidemiology and drivers of antimicrobial resistance in low-income countries.}, language = {en} } @article{BauerConchaMendozaKreienbrocketal.2022, author = {Bauer, Hannah and Concha Mendoza, Gustavo Andr{\´e}s and Kreienbrock, Lothar and Hartmann, Maria and Frickmann, Hagen and Kann, Simone}, title = {Prevalence of common diseases in Indigenous people in Colombia}, series = {Tropical Medicine and Infectious Disease}, volume = {7}, journal = {Tropical Medicine and Infectious Disease}, number = {6}, issn = {2414-6366}, doi = {10.3390/tropicalmed7060109}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-278953}, year = {2022}, abstract = {The Indigenous tribe called the Wiwa lives retracted in the Sierra Nevada de Santa Marta, Colombia. Little is known about their health status and whether the health care system in place covers their needs. In 2017 and 2018, a permanent physician was in charge for the Wiwa. Diseases and complaints were registered, ranked, and classified with the ICD-10 coding. Datasets from the Indigenous health care provider Dusakawi, collected from local health points and health brigades travelling sporadically into the fields for short visits, were compared. Furthermore, a list of provided medication was evaluated regarding the recorded needs. The most common complaints found were respiratory, infectious and parasitic, and digestive diseases. The top ten diagnoses collected in the health points and in the health brigade datasets were similar, although with a different ranking. The available medication showed a basic coverage only, with a critical lack of treatment for many severe, chronic, and life-threatening diseases. Most of the detected diseases in the Indigenous population are avoidable by an improvement in health care access, an expansion of the provided medication, and an increase in knowledge, hygiene, and life standards.}, language = {en} } @article{StrobelSickenbergerSchoenetal.2022, author = {Strobel, Katharina and Sickenberger, Christina and Schoen, Christoph and Kneitz, Hermann and Kolb-M{\"a}urer, Annette and Goebeler, Matthias}, title = {Diagnosis and therapy of Mycobacterium marinum: a single-center 21-year retrospective analysis}, series = {Journal der Deutschen Dermatologischen Gesellschaft}, volume = {20}, journal = {Journal der Deutschen Dermatologischen Gesellschaft}, number = {9}, doi = {10.1111/ddg.14847}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-318428}, pages = {1211 -- 1218}, year = {2022}, abstract = {Background and Objectives In Europe, infections with Mycobacterium (M.) marinum are rare. We conducted a retrospective single-center study to assess the clinical spectrum of M. marinum infection and its diagnosis, treatment and outcome under real-world conditions. Patients and Methods Eighteen patients presenting with M. marinum infections between 1998 and 2018 were identified in the data warehouse of the University Hospital W{\"u}rzburg and considered for detailed analysis. Results Twelve patients reported aquatic exposure. In 16/18 cases the upper extremities were affected. No invasive infections were detected. Mean time to diagnosis was 15 weeks. Histology revealed granulomatous inflammation in 14 patients while mycobacterial cultures were positive for M. marinum in 16 cases. Most patients received antibiotic monotherapy (14/18) while combination therapy was administered in four cases. Treatment (with a median duration of 10 weeks) was successful in 13 patients. Five patients were lost to follow-up. Conclusions Our retrospective analysis of M. marinum infections at a German tertiary referral center revealed a considerable diagnostic delay and the relevance of microbiological culture, PCR and histology for diagnosis. Monotherapy with clarithromycin (rather than doxycycline) appeared as a reasonable treatment option while immunosuppressed or -compromised patients and those with extended disease received combination therapy.}, language = {en} } @article{NieuwenhuizenEvans2022, author = {Nieuwenhuizen, Natalie E. and Evans, Joanna C.}, title = {Cellular and molecular mechanisms in mycobacterial infection}, series = {International Journal of Molecular Sciences}, volume = {23}, journal = {International Journal of Molecular Sciences}, number = {13}, issn = {1422-0067}, doi = {10.3390/ijms23137205}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-284370}, year = {2022}, abstract = {No abstract available}, language = {en} } @article{StreckForstervonHertzbergBoelchetal.2022, author = {Streck, Laura Elisa and Forster, Johannes and von Hertzberg-Boelch, Sebastian Philipp and Reichel, Thomas and Rudert, Maximilian and Rueckl, Kilian}, title = {The role of synovial fluid aspiration in shoulder joint infections}, series = {BMC Musculoskeletal Disorders}, volume = {23}, journal = {BMC Musculoskeletal Disorders}, doi = {10.1186/s12891-022-05285-x}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-300795}, year = {2022}, abstract = {Background Joint aspiration with analysis of synovial fluid white blood cell count (WBC) and microbiological culture is a widely established aspect in the diagnosis of shoulder joint infections (SJI). In case of a two stage revision for SJI, joint aspiration before re-/implantation of a total shoulder arthroplasty (TSA) was used to rule out persistent infection for years but its value is under debate. Shoulder specific data on all aspects is rare. The current study aims to answer the following research questions: Does joint aspiration have an insufficient predictive value in the diagnosis of SJI in (1) initial workup and (2) before definite arthroplasty with polymethylmethacrylate (PMMA)-Spacer in place? Methods This retrospective evaluation investigates 35 patients that were treated for SJI with a two staged implantation of a TSA after debridement and implantation of an PMMA-Spacer. Joint aspirations were performed preoperatively (PA) and before re-/implantation of the prosthesis while spacer was in place (interstage aspiration, IA). Samples were taken for microbiological culture and analysis of WBC. Sensitivity and specificity were calculated with reference to intraoperative microbiological samples. Receiver Operating Characteristic (ROC), Area-Under-Curve analysis (AUC) and calculation of the Youden index were performed to find optimum cut-off for WBC. Results The sensitivity of microbiological cultures from PA was 58.3\% and the specificity was 88.9\%. The mean WBC was 27,800 leucocytes/mm3 (range 400-96,300). The maximum Youden index (0.857) was a cut-off of 2600 leucocytes/mm3 with a sensitivity of 85.7\% and a specificity of 100.0\%. The sensitivity and specificity of IA were 0.0\% and 88.5\%, respectively. Conclusions Preoperative aspiration is likely to miss Cutibacteria spp. and CoNS and cannot rule out infection for sure. However, we recommend it for its advantages of targeted antibiotic therapy in case of germ identification. Empiric antibiotic therapy should cover Cutibacteria and CoNS even if aspiration showed negative microbiological cultures. In contrast, the diagnostic value of interstage aspiration does not qualify for its routine use.}, language = {en} } @phdthesis{Schlag2017, author = {Schlag, Stephanie}, title = {Mikrobiologie, Klinik und Antibiotika-Therapie invasiver bakterieller Infektionen an der W{\"u}rzburger Universit{\"a}ts-Kinderklinik zwischen 2006 und 2012}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-156236}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2017}, abstract = {In einem Zeitraum von sieben Jahren untersuchten wir invasive bakterielle Infektionen bei Kindern durch die wichtigsten Erreger von Blutstrombahninfektionen an der W{\"u}rzburger Universit{\"a}ts-Kinderklinik.}, subject = {Antibiotikum}, language = {de} } @article{StockPetrašMelteretal.2016, author = {Stock, Nina Katharina and Petr{\´a}š, Petr and Melter, Oto and Kapounov{\´a}, Gabriela and Vopalkov{\´a}, Petra and Kubele, Jan and Vaniš, V{\´a}clav and Tkadlec, Jan and Buk{\´a}čkov{\´a}, Eva and Machov{\´a}, Ivana and Jindr{\´a}k, Vlastimil}, title = {Importance of Multifaceted Approaches in Infection Control: A Practical Experience from an Outbreak Investigation}, series = {PLoS ONE}, volume = {11}, journal = {PLoS ONE}, number = {6}, doi = {10.1371/journal.pone.0157981}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-166891}, pages = {e0157981}, year = {2016}, abstract = {Background This study presents the results of a multidisciplinary, nosocomial MRSA outbreak investigation in an 8-bed medical intensive care unit (ICU). The identification of seven MRSA positive patients in the beginning of 2014 led to the closure of the ward for several weeks. A multidisciplinary, retrospective investigation was initiated in order to identify the reason and the source for the outbreak, describe MRSA transmission in the department and identify limitations in infection control. Methods The investigation comprised an epidemiological description of MRSA cases from 2012 to 2014 and a characterization of MRSA isolates, including phage-, spa- and PFGE-typing. Additionally, MRSA screening was performed from the hospital staff and the environment. To identify the reason for the outbreak, work-related, psychological and behavioral factors were investigated by impartial audits and staff interviews. Results Thirty-one MRSA cases were registered during the study period, and 36 isolates were investigated. Molecular typing determined the outbreak strain (phage type 54/812, PFGE type A4, spa type t003) and identified the probable index case. Nasal carriage in one employee and a high environmental contamination with the outbreak strain was documented. Important gaps in nursing procedures and general management were identified. Elevated stress levels and communication problems preceded the outbreak. Compliance with hand hygiene and isolation procedures was evaluated as appropriate. Conclusion This study demonstrates the complexity of controlling hospital-associated infections. The combined use of different typing methods is beneficial for outbreak investigations. Psychological, behavioral and other work-related factors have an important impact on the spread of nosocomial pathogens. These factors should be addressed and integrated in routine infection control practice.}, language = {en} } @article{PetersFohmannRudeletal.2021, author = {Peters, Simon and Fohmann, Ingo and Rudel, Thomas and Schubert-Unkmeir, Alexandra}, title = {A Comprehensive Review on the Interplay between Neisseria spp. and Host Sphingolipid Metabolites}, series = {Cells}, volume = {10}, journal = {Cells}, number = {11}, issn = {2073-4409}, doi = {10.3390/cells10113201}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-250203}, year = {2021}, abstract = {Sphingolipids represent a class of structural related lipids involved in membrane biology and various cellular processes including cell growth, apoptosis, inflammation and migration. Over the past decade, sphingolipids have become the focus of intensive studies regarding their involvement in infectious diseases. Pathogens can manipulate the sphingolipid metabolism resulting in cell membrane reorganization and receptor recruitment to facilitate their entry. They may recruit specific host sphingolipid metabolites to establish a favorable niche for intracellular survival and proliferation. In contrast, some sphingolipid metabolites can also act as a first line defense against bacteria based on their antimicrobial activity. In this review, we will focus on the strategies employed by pathogenic Neisseria spp. to modulate the sphingolipid metabolism and hijack the sphingolipid balance in the host to promote cellular colonization, invasion and intracellular survival. Novel techniques and innovative approaches will be highlighted that allow imaging of sphingolipid derivatives in the host cell as well as in the pathogen.}, language = {en} } @article{ApsemidouFuellerIdelevichetal.2020, author = {Apsemidou, Athanasia and F{\"u}ller, Miriam Antonie and Idelevich, Evgeny A. and Kurzai, Oliver and Tragiannidis, Athanasios and Groll, Andreas H.}, title = {Candida lusitaniae breakthrough fungemia in an immuno-compromised adolescent: case report and review of the literature}, series = {Journal of Fungi}, volume = {6}, journal = {Journal of Fungi}, number = {4}, issn = {2309-608X}, doi = {10.3390/jof6040380}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-220125}, year = {2020}, abstract = {Candida lusitaniae is a rare cause of candidemia that is known for its unique capability to rapidly acquire resistance to amphotericin B. We report the case of an adolescent with grade IV graft-vs.-host disease after hematopoietic cell transplantation who developed catheter-associated C. lusitaniae candidemia while on therapeutic doses of liposomal amphotericin B. We review the epidemiology of C. lusitaniae bloodstream infections in adult and pediatric patients, the development of resistance, and its role in breakthrough candidemia. Appropriate species identification, in vitro susceptibility testing, and source control are pivotal to optimal management of C. lusitaniae candidemia. Initial antifungal therapy may consist of an echinocandin and be guided by in vitro susceptibility and clinical response.}, language = {en} } @article{KochHellenbrandSchinketal.2016, author = {Koch, J. and Hellenbrand, W. and Schink, S. and Wichmann, O. and Carganico, A. and Drewes, J. and Kruspe, M. and Suckau, M. and Claus, H. and Marcus, U.}, title = {Evaluation of a temporary vaccination recommendation in response to an outbreak of invasive meningococcal serogroup C disease in men who have sex with men in Berlin, 2013-2014}, series = {Eurosurveillance}, volume = {21}, journal = {Eurosurveillance}, number = {5}, doi = {10.2807/1560-7917.ES.2016.21.5.30122}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-165070}, pages = {pii=30122}, year = {2016}, abstract = {Meningococcal serogroup C (MenC) vaccination of men who have sex with men (MSM) was temporarily recommended to control an outbreak of invasive MenC disease among MSM in Berlin in 2012-2013. Vaccination was offered to HIV-infected MSM free of charge; others had to request reimbursement or pay out of pocket. We aimed to assess (i) awareness and acceptance of this recommendation through an online survey of MSM, (ii) implementation through a survey of primary care physicians and analysis of vaccine prescriptions, and (iii) impact through analysis of notified cases. Among online survey respondents, 60\% were aware of the recommendation. Of these, 39\% had obtained vaccination (70\% of HIV-infected, 13\% of HIV-negative/non-tested MSM). Awareness of recommendation and vaccination were positively associated with HIV infection, primary care physicians' awareness of respondents' sexual orientation, and exposure to multiple information sources. Most (26/30) physicians informed clients about the recommendation. Physicians considered concerns regarding reimbursement, vaccine safety and lack of perceived disease risk as primary barriers. After the recommendation, no further outbreak-related cases occurred. To reach and motivate target groups, communication of a new outbreak-related vaccination recommendation should address potential concerns through as many information channels as possible and direct reimbursement of costs should be enabled.}, language = {en} } @article{WeissSchlegelTerpitzetal.2020, author = {Weiss, Esther and Schlegel, Jan and Terpitz, Ulrich and Weber, Michael and Linde, J{\"o}rg and Schmitt, Anna-Lena and H{\"u}nniger, Kerstin and Marischen, Lothar and Gamon, Florian and Bauer, Joachim and L{\"o}ffler, Claudia and Kurzai, Oliver and Morton, Charles Oliver and Sauer, Markus and Einsele, Hermann and Loeffler, Juergen}, title = {Reconstituting NK Cells After Allogeneic Stem Cell Transplantation Show Impaired Response to the Fungal Pathogen Aspergillus fumigatus}, series = {Frontiers in Immunology}, volume = {11}, journal = {Frontiers in Immunology}, issn = {1664-3224}, doi = {10.3389/fimmu.2020.02117}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-212581}, year = {2020}, abstract = {Delayed natural killer (NK) cell reconstitution after allogeneic stem cell transplantation (alloSCT) is associated with a higher risk of developing invasive aspergillosis. The interaction of NK cells with the human pathogen Aspergillus (A.) fumigatus is mediated by the fungal recognition receptor CD56, which is relocated to the fungal interface after contact. Blocking of CD56 signaling inhibits the fungal mediated chemokine secretion of MIP-1α, MIP-1β, and RANTES and reduces cell activation, indicating a functional role of CD56 in fungal recognition. We collected peripheral blood from recipients of an allograft at defined time points after alloSCT (day 60, 90, 120, 180). NK cells were isolated, directly challenged with live A. fumigatus germ tubes, and cell function was analyzed and compared to healthy age and gender-matched individuals. After alloSCT, NK cells displayed a higher percentage of CD56\(^{bright}\)CD16\(^{dim}\) cells throughout the time of blood collection. However, CD56 binding and relocalization to the fungal contact side were decreased. We were able to correlate this deficiency to the administration of corticosteroid therapy that further negatively influenced the secretion of MIP-1α, MIP-1β, and RANTES. As a consequence, the treatment of healthy NK cells ex vivo with corticosteroids abrogated chemokine secretion measured by multiplex immunoassay. Furthermore, we analyzed NK cells regarding their actin cytoskeleton by Structured Illumination Microscopy (SIM) and flow cytometry and demonstrate an actin dysfunction of NK cells shown by reduced F-actin content after fungal co-cultivation early after alloSCT. This dysfunction remains until 180 days post-alloSCT, concluding that further actin-dependent cellular processes may be negatively influenced after alloSCT. To investigate the molecular pathomechansism, we compared CD56 receptor mobility on the plasma membrane of healthy and alloSCT primary NK cells by single-molecule tracking. The results were very robust and reproducible between tested conditions which point to a different molecular mechanism and emphasize the importance of proper CD56 mobility.}, language = {en} } @article{NyawaleMoremiMohamedetal.2022, author = {Nyawale, Helmut A. and Moremi, Nyambura and Mohamed, Mohamed and Njwalila, Johnson and Silago, Vitus and Krone, Manuel and Konje, Eveline T. and Mirambo, Mariam M. and Mshana, Stephen E.}, title = {High seroprevalence of SARS-CoV-2 in Mwanza, northwestern Tanzania: a population-based survey}, series = {International Journal of Environmental Research and Public Health}, volume = {19}, journal = {International Journal of Environmental Research and Public Health}, number = {18}, issn = {1660-4601}, doi = {10.3390/ijerph191811664}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-288134}, year = {2022}, abstract = {The transmission of the SARS-CoV-2 virus, which causes COVID-19, has been documented worldwide. However, the evidence of the extent to which transmission has occurred in different countries is still to be established. Understanding the magnitude and distribution of SARS-CoV-2 through seroprevalence studies is important in designing control and preventive strategies in communities. This study investigated the seropositivity of the SARS-CoV-2 virus antibodies in the communities of three different districts in the Mwanza region, Tanzania. A household cross-sectional survey was conducted in September 2021 using the modified African Centre for Disease and Prevention (ACDC) survey protocol. A blood sample was obtained from one member of each of the selected households who consented to take part in the survey. Immunochromatographic rapid test kits were used to detect IgM and IgG SARS-CoV-2 antibodies, followed by descriptive data analysis. Overall, 805 participants were enrolled in the study with a median age of 35 (interquartile range (IQR):27-47) years. The overall SARS-CoV-2 seropositivity was 50.4\% (95\%CI: 46.9-53.8\%). The IgG and IgM seropositivity of the SARS-CoV-2 antibodies was 49.3\% and 7.2\%, respectively, with 6.1\% being both IgG and IgM seropositive. A history of runny nose (aOR: 1.84, 95\%CI: 1.03-3.5, p = 0.036), loss of taste (aOR: 1.84, 95\%CI: 1.12-4.48, p = 0.023), and living in Ukerewe (aOR: 3.55, 95\%CI: 1.68-7.47, p = 0.001) and Magu (aOR: 2.89, 95\%CI: 1.34-6.25, p= 0.007) were all independently associated with SARS-CoV-2 IgM seropositivity. Out of the studied factors, living in the Ukerewe district was independently associated with IgG seropositivity (aOR 1.29, CI 1.08-1.54, p = 0.004). Twenty months after the first case of COVID-19 in Tanzania, about half of the studied population in Mwanza was seropositive for SARS-CoV-2.}, language = {en} } @article{StraubStapfFischeretal.2022, author = {Straub, Anton and Stapf, Maximilian and Fischer, Markus and Vollmer, Andreas and Linz, Christian and L{\^a}m, Thi{\^e}n-Tr{\´i} and K{\"u}bler, Alexander and Brands, Roman C. and Scherf-Clavel, Oliver and Hartmann, Stefan}, title = {Bone concentration of ampicillin/sulbactam: a pilot study in patients with osteonecrosis of the jaw}, series = {International Journal of Environmental Research and Public Health}, volume = {19}, journal = {International Journal of Environmental Research and Public Health}, number = {22}, issn = {1660-4601}, doi = {10.3390/ijerph192214917}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-297413}, year = {2022}, abstract = {Osteonecrosis of the jaw (ONJ) occurs typically after irradiation of the head and neck area or after the intake of antiresorptive agents. Both interventions can lead to compromised bone perfusion and can ultimately result in infection and necrosis. Treatment usually consists of surgical necrosectomy and prolonged antibiotic therapy, usually through beta-lactams such as ampicillin/sulbactam. The poor blood supply in particular raises the question as to whether this form of antibiosis can achieve sufficient concentrations in the bone. Therefore, we investigated the antibiotic concentration in plasma and bone samples in a prospective study. Bone samples were collected from the necrosis core and in the vital surrounding bone. The measured concentrations in plasma for ampicillin and sulbactam were 126.3 ± 77.6 and 60.2 ± 35.0 µg/mL, respectively. In vital bone and necrotic bone samples, the ampicillin/sulbactam concentrations were 6.3 ± 7.8/1.8 ± 2.0 µg/g and 4.9 ± 7.0/1.7 ± 1.7 µg/g, respectively. These concentrations are substantially lower than described in the literature. However, the concentration seems sufficient to kill most bacteria, such as Streptococci and Staphylococci, which are mostly present in the biofilm of ONJ. We, therefore, conclude that intravenous administration of ampicillin/sulbactam remains a valuable treatment in the therapy of ONJ. Nevertheless, increasing resistance of Escherichia coli towards beta-lactam antibiotics have been reported and should be considered.}, language = {en} } @article{SilwedelHaarmannFehrholzetal.2019, author = {Silwedel, Christine and Haarmann, Axel and Fehrholz, Markus and Claus, Heike and Speer, Christian P. and Glaser, Kirsten}, title = {More than just inflammation: Ureaplasma species induce apoptosis in human brain microvascular endothelial cells}, series = {Journal of Neuroinflammation}, volume = {16}, journal = {Journal of Neuroinflammation}, doi = {10.1186/s12974-019-1413-8}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-200711}, pages = {38}, year = {2019}, abstract = {Background Ureaplasma species (spp.) are commonly regarded as low-virulent commensals but may cause invasive diseases in immunocompromised adults and in neonates, including neonatal meningitis. The interactions of Ureaplasma spp. with host defense mechanisms are poorly understood. This study addressed Ureaplasma-driven cell death, concentrating on apoptosis as well as inflammatory cell death. Methods Human brain microvascular endothelial cells (HBMEC) were exposed to Ureaplasma (U.) urealyticum serovar 8 (Uu8) and U. parvum serovar 3 (Up3). Resulting numbers of dead cells as well as mRNA levels and enzyme activity of key agents in programmed cell death were assessed by flow cytometry, RNA sequencing, and qRT-PCR, respectively. xCELLigence data were used for real-time monitoring of changes in cell adhesion properties. Results Both Ureaplasma isolates induced cell death (p < 0.05, vs. broth). Furthermore, Ureaplasma spp. enhanced mRNA levels for genes in apoptosis, including caspase 3 (Up3 p < 0.05, vs. broth), caspase 7 (p < 0.01), and caspase 9 (Up3 p < 0.01). Caspase 3 activity was increased upon Uu8 exposure (p < 0.01). Vice versa, Ureaplasma isolates downregulated mRNA levels for proteins involved in inflammatory cell death, namely caspase 1 (Uu8 p < 0.01, Up3 p < 0.001), caspase 4 (Uu8 p < 0.05, Up3 p < 0.01), NOD-like receptor pyrin domain-containing 3 (Uu8 p < 0.05), and receptor-interacting protein kinase 3 (p < 0.05). Conclusions By inducing apoptosis in HBMEC as main constituents of the blood-brain barrier, Ureaplasma spp. may provoke barrier breakdown. Simultaneous suppression of inflammatory cell death may additionally attenuate host defense strategies. Ultimate consequence could be invasive and long-term CNS infections by Ureaplasma spp.}, language = {en} } @article{ZoranSeelbinderWhiteetal.2022, author = {Zoran, Tamara and Seelbinder, Bastian and White, Philip Lewis and Price, Jessica Sarah and Kraus, Sabrina and Kurzai, Oliver and Linde, Joerg and H{\"a}der, Antje and Loeffler, Claudia and Grigoleit, Goetz Ulrich and Einsele, Hermann and Panagiotou, Gianni and Loeffler, Juergen and Sch{\"a}uble, Sascha}, title = {Molecular profiling reveals characteristic and decisive signatures in patients after allogeneic stem cell transplantation suffering from invasive pulmonary aspergillosis}, series = {Journal of Fungi}, volume = {8}, journal = {Journal of Fungi}, number = {2}, issn = {2309-608X}, doi = {10.3390/jof8020171}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-262105}, year = {2022}, abstract = {Despite available diagnostic tests and recent advances, diagnosis of pulmonary invasive aspergillosis (IPA) remains challenging. We performed a longitudinal case-control pilot study to identify host-specific, novel, and immune-relevant molecular candidates indicating IPA in patients post allogeneic stem cell transplantation (alloSCT). Supported by differential gene expression analysis of six relevant in vitro studies, we conducted RNA sequencing of three alloSCT patients categorized as probable IPA cases and their matched controls without Aspergillus infection (66 samples in total). We additionally performed immunoassay analysis for all patient samples to gain a multi-omics perspective. Profiling analysis suggested LGALS2, MMP1, IL-8, and caspase-3 as potential host molecular candidates indicating IPA in investigated alloSCT patients. MMP1, IL-8, and caspase-3 were evaluated further in alloSCT patients for their potential to differentiate possible IPA cases and patients suffering from COVID-19-associated pulmonary aspergillosis (CAPA) and appropriate control patients. Possible IPA cases showed differences in IL-8 and caspase-3 serum levels compared with matched controls. Furthermore, we observed significant differences in IL-8 and caspase-3 levels among CAPA patients compared with control patients. With our conceptual work, we demonstrate the potential value of considering the human immune response during Aspergillus infection to identify immune-relevant molecular candidates indicating IPA in alloSCT patients. These human host candidates together with already established fungal biomarkers might improve the accuracy of IPA diagnostic tools.}, language = {en} } @article{WaltherWagnerKurzai2019, author = {Walther, Grit and Wagner, Lysett and Kurzai, Oliver}, title = {Updates on the taxonomy of Mucorales with an emphasis on clinically important taxa}, series = {Journal of Fungi}, volume = {5}, journal = {Journal of Fungi}, number = {4}, issn = {2309-608X}, doi = {10.3390/jof5040106}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-193081}, year = {2019}, abstract = {Fungi of the order Mucorales colonize all kinds of wet, organic materials and represent a permanent part of the human environment. They are economically important as fermenting agents of soybean products and producers of enzymes, but also as plant parasites and spoilage organisms. Several taxa cause life-threatening infections, predominantly in patients with impaired immunity. The order Mucorales has now been assigned to the phylum Mucoromycota and is comprised of 261 species in 55 genera. Of these accepted species, 38 have been reported to cause infections in humans, as a clinical entity known as mucormycosis. Due to molecular phylogenetic studies, the taxonomy of the order has changed widely during the last years. Characteristics such as homothallism, the shape of the suspensors, or the formation of sporangiola are shown to be not taxonomically relevant. Several genera including Absidia, Backusella, Circinella, Mucor, and Rhizomucor have been amended and their revisions are summarized in this review. Medically important species that have been affected by recent changes include Lichtheimia corymbifera, Mucor circinelloides, and Rhizopus microsporus. The species concept of Rhizopus arrhizus (syn. R. oryzae) is still a matter of debate. Currently, species identification of the Mucorales is best performed by sequencing of the internal transcribed spacer (ITS) region. Ecologically, the Mucorales represent a diverse group but for the majority of taxa, the ecological role and the geographic distribution remain unknown. Understanding the biology of these opportunistic fungal pathogens is a prerequisite for the prevention of infections, and, consequently, studies on the ecology of the Mucorales are urgently needed.}, language = {en} } @article{AmpattuHagmannLiangetal.2017, author = {Ampattu, Biju Joseph and Hagmann, Laura and Liang, Chunguang and Dittrich, Marcus and Schl{\"u}ter, Andreas and Blom, Jochen and Krol, Elizaveta and Goesmann, Alexander and Becker, Anke and Dandekar, Thomas and M{\"u}ller, Tobias and Schoen, Christoph}, title = {Transcriptomic buffering of cryptic genetic variation contributes to meningococcal virulence}, series = {BMC Genomics}, volume = {18}, journal = {BMC Genomics}, number = {282}, doi = {10.1186/s12864-017-3616-7}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-157534}, year = {2017}, abstract = {Background: Commensal bacteria like Neisseria meningitidis sometimes cause serious disease. However, genomic comparison of hyperinvasive and apathogenic lineages did not reveal unambiguous hints towards indispensable virulence factors. Here, in a systems biological approach we compared gene expression of the invasive strain MC58 and the carriage strain α522 under different ex vivo conditions mimicking commensal and virulence compartments to assess the strain-specific impact of gene regulation on meningococcal virulence. Results: Despite indistinguishable ex vivo phenotypes, both strains differed in the expression of over 500 genes under infection mimicking conditions. These differences comprised in particular metabolic and information processing genes as well as genes known to be involved in host-damage such as the nitrite reductase and numerous LOS biosynthesis genes. A model based analysis of the transcriptomic differences in human blood suggested ensuing metabolic flux differences in energy, glutamine and cysteine metabolic pathways along with differences in the activation of the stringent response in both strains. In support of the computational findings, experimental analyses revealed differences in cysteine and glutamine auxotrophy in both strains as well as a strain and condition dependent essentiality of the (p)ppGpp synthetase gene relA and of a short non-coding AT-rich repeat element in its promoter region. Conclusions: Our data suggest that meningococcal virulence is linked to transcriptional buffering of cryptic genetic variation in metabolic genes including global stress responses. They further highlight the role of regulatory elements for bacterial virulence and the limitations of model strain approaches when studying such genetically diverse species as N. meningitidis.}, language = {en} } @article{KlughammerDittrichBlometal.2017, author = {Klughammer, Johanna and Dittrich, Marcus and Blom, Jochen and Mitesser, Vera and Vogel, Ulrich and Frosch, Matthias and Goesmann, Alexander and M{\"u}ller, Tobias and Schoen, Christoph}, title = {Comparative genome sequencing reveals within-host genetic changes in Neisseria meningitidis during invasive disease}, series = {PLoS ONE}, volume = {12}, journal = {PLoS ONE}, number = {1}, doi = {10.1371/journal.pone.0169892}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-159547}, pages = {e0169892}, year = {2017}, abstract = {Some members of the physiological human microbiome occasionally cause life-threatening disease even in immunocompetent individuals. A prime example of such a commensal pathogen is Neisseria meningitidis, which normally resides in the human nasopharynx but is also a leading cause of sepsis and epidemic meningitis. Using N. meningitidis as model organism, we tested the hypothesis that virulence of commensal pathogens is a consequence of within host evolution and selection of invasive variants due to mutations at contingency genes, a mechanism called phase variation. In line with the hypothesis that phase variation evolved as an adaptation to colonize diverse hosts, computational comparisons of all 27 to date completely sequenced and annotated meningococcal genomes retrieved from public databases showed that contingency genes are indeed enriched for genes involved in host interactions. To assess within-host genetic changes in meningococci, we further used ultra-deep whole-genome sequencing of throat-blood strain pairs isolated from four patients suffering from invasive meningococcal disease. We detected up to three mutations per strain pair, affecting predominantly contingency genes involved in type IV pilus biogenesis. However, there was not a single (set) of mutation(s) that could invariably be found in all four pairs of strains. Phenotypic assays further showed that these genetic changes were generally not associated with increased serum resistance, higher fitness in human blood ex vivo or differences in the interaction with human epithelial and endothelial cells in vitro. In conclusion, we hypothesize that virulence of meningococci results from accidental emergence of invasive variants during carriage and without within host evolution of invasive phenotypes during disease progression in vivo.}, language = {en} } @article{DichtlForsterOrmannsetal.2020, author = {Dichtl, Karl and Forster, Johannes and Ormanns, Steffen and Horns, Heidi and Suerbaum, Sebastian and Seybold, Ulrich and Wagener, Johannes}, title = {Comparison of β-D-Glucan and galactomannan in serum for detection of invasive aspergillosis: retrospective analysis with focus on early diagnosis}, series = {Journal of Fungi}, volume = {6}, journal = {Journal of Fungi}, number = {4}, issn = {2309-608X}, doi = {10.3390/jof6040253}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-216298}, year = {2020}, abstract = {The early diagnosis of invasive aspergillosis (IA) relies mainly on computed tomography imaging and testing for fungal biomarkers such as galactomannan (GM). We compared an established ELISA for the detection of GM with a turbidimetric assay for detection of the panfungal biomarker β-D-glucan (BDG) for early diagnosis of IA. A total of 226 serum specimens from 47 proven and seven probable IA cases were analysed. Sensitivity was calculated for samples obtained closest to the day of IA-diagnosis (d0). Additional analyses were performed by including samples obtained during the presumed course of disease. Most IA cases involved the respiratory system (63\%), and Aspergillus fumigatus was the most frequently isolated species (59\%). For proven cases, sensitivity of BDG/GM analysis was 57\%/40\%. Including all samples dating from -6 to +1 weeks from d0 increased sensitivities to 74\%/51\%. Sensitivity of BDG testing was as high as or higher than GM testing for all subgroups and time intervals analysed. BDG testing was less specific (90-93\%) than GM testing (99-100\%). Combining BDG and GM testing resulted in sensitivity/specificity of 70\%/91\%. Often, BDG testing was positive before GM testing. Our study backs the use of BDG for diagnosis of suspected IA. We suggest combining BDG and GM to improve the overall sensitivity.}, language = {en} } @article{SattlerNosterBrunkeetal.2021, author = {Sattler, Janko and Noster, Janina and Brunke, Anne and Plum, Georg and Wiegel, Pia and Kurzai, Oliver and Meis, Jacques F. and Hamprecht, Axel}, title = {Comparison of two commercially available qPCR kits for the detection of Candida auris}, series = {Journal of Fungi}, volume = {7}, journal = {Journal of Fungi}, number = {2}, issn = {2309-608X}, doi = {10.3390/jof7020154}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-228879}, year = {2021}, abstract = {Candida auris is an emerging pathogen with resistance to many commonly used antifungal agents. Infections with C. auris require rapid and reliable detection methods to initiate successful medical treatment and contain hospital outbreaks. Conventional identification methods are prone to errors and can lead to misidentifications. PCR-based assays, in turn, can provide reliable results with low turnaround times. However, only limited data are available on the performance of commercially available assays for C. auris detection. In the present study, the two commercially available PCR assays AurisID (OLM, Newcastle Upon Tyne, UK) and Fungiplex Candida Auris RUO Real-Time PCR (Bruker, Bremen, Germany) were challenged with 29 C. auris isolates from all five clades and eight other Candida species as controls. AurisID reliably detected C. auris with a limit of detection (LoD) of 1 genome copies/reaction. However, false positive results were obtained with high DNA amounts of the closely related species C. haemulonii, C. duobushaemulonii and C. pseudohaemulonii. The Fungiplex Candida Auris RUO Real-Time PCR kit detected C. auris with an LoD of 9 copies/reaction. No false positive results were obtained with this assay. In addition, C. auris could also be detected in human blood samples spiked with pure fungal cultures by both kits. In summary, both kits could detect C. auris-DNA at low DNA concentrations but differed slightly in their limits of detection and specificity.}, language = {en} } @phdthesis{vonPapen2019, author = {von Papen, Hans Michael}, title = {Untersuchungen zum Einfluss der Meningokokkeninfektion auf den Zellzyklus von Epithelzellen}, doi = {10.25972/OPUS-19286}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-192862}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2019}, abstract = {Zahlreiche humanpathogene bakterielle Erreger k{\"o}nnen ihre F{\"a}higkeit zur Kolonisation epithelialer Barrieren optimieren, indem sie mit dem Zellzyklus der infizierten Wirtszelle in Wechselwirkung treten und so die Abschilferung und Erneuerung des Epithels verz{\"o}gern. Die hierbei wirksamen bakteriellen Effektoren sind als „Cyclomoduline" bekannt und gelten als neue Klasse bakterieller Pathogenit{\"a}tsfaktoren. Ziel der vorliegenden Promotionsarbeit war es zu untersuchen, ob durch die Infektion menschlicher pharyngealer Epithelzellen mit N. meningitidis der Zellzyklus der Wirtszelle beeinflusst wird. Mit zwei verschiedenen Untersuchungsmethoden konnte {\"u}bereinstimmend gezeigt werden, dass die Infektion der Epithelzelllinie Detroit 562 mit verschiedenen Meningokokkenisolaten zu einer signifikanten Akkumulation von Epithelzellen in der G1-Phase f{\"u}hrte. Dieser Effekt wurde sowohl von pathogenen Meningokokkenst{\"a}mmen als auch von Tr{\"a}gerst{\"a}mmen ausgel{\"o}st, jedoch nur durch Isolate, die f{\"a}hig zur Adh{\"a}renz und zur Invasion in die Epithelzelle waren. Durch Hitzebehandlung der Bakterien konnte der Zellzyklusarrest vollst{\"a}ndig aufgehoben werden. Ebenso konnte der Effekt durch Inkubation der Epithelzellen mit bakteriellen Kultur{\"u}berst{\"a}nden und durch Infektion der Zellen mit E. coli-St{\"a}mmen, welche die Meningokokkenadh{\"a}sine Opa und Opc {\"u}berexprimieren, nicht ausgel{\"o}st werden. Es konnte weiterhin nachgewiesen werden, dass die Infektion mit N. meningitidis in der Zielzelle zu einer signifikant gesteigerten Expression des CDK-Inhibitors p21WAF1/Cip1 f{\"u}hrte, begleitet von einer vermehrten Lokalisation im Zellkern. Auch zeigte sich eine ver{\"a}nderte Proteinexpression der f{\"u}r die G1-Phase relevanten Cycline D und E. Diese scheint sich erst posttranslational zu ereignen, da die unterschiedliche Expression auf mRNA-Ebene nicht festgestellt werden konnte. Zusammenfassend konnte dargestellt werden, dass die Infektion von Pharynxepithelzellen mit lebenden, zur Adh{\"a}renz und Invasion f{\"a}higen Meningokokkenst{\"a}mmen in der menschlichen Zielzelle einen Zellzyklusarrest in der G1-Phase verursacht, vermutlich durch ver{\"a}nderte Expression der Zellzyklusregulatoren p21WAF1/Cip1, Cyclin D und Cyclin E. M{\"o}glicherweise stellt die Induktion dieses Zellzyklusarrestes einen wichtigen Schritt in der Pathogenese der bakteriellen Kolonisation des oberen Atemwegsepithels durch N. meningitidis dar.}, subject = {Neisseria meningitidis}, language = {de} } @article{StreckGaalForsteretal.2021, author = {Streck, Laura Elisa and Gaal, Chiara and Forster, Johannes and Konrads, Christian and Hertzberg-Boelch, Sebastian Philipp von and Rueckl, Kilian}, title = {Defining a synovial fluid white blood cell count threshold to predict periprosthetic infection after shoulder arthroplasty}, series = {Journal of Clinical Medicine}, volume = {11}, journal = {Journal of Clinical Medicine}, number = {1}, issn = {2077-0383}, doi = {10.3390/jcm11010050}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-252275}, year = {2021}, abstract = {Background: The diagnosis of periprosthetic shoulder infection (PSI) requires a thorough diagnostic workup. Synovial fluid aspiration has been proven to be a reliable tool in the diagnosis of joint infections of the lower extremity, but shoulder specific data is limited. This study defines a threshold for synovial fluid white blood cell count (WBC) and assesses the reliability of microbiological cultures. Methods: Retrospective study of preoperative and intraoperative fluid aspiration of 31 patients who underwent a revision of a shoulder arthroplasty (15 with PSI defined by IDSA criteria, 16 without infection). The threshold for WBC was calculated by ROC/AUC analysis. Results: WBC was significantly higher in patients with PSI than in other patients. A threshold of 2800 leucocytes/mm\(^3\) showed a sensitivity of 87\% and a specificity of 88\% (AUROC 0.92). Microbiological cultures showed a sensitivity of 76\% and a specificity of 100\%. Conclusions: A threshold of 2800 leucocytes/mm\(^3\) in synovial fluid can be recommended to predict PSI. Microbiological culture has an excellent specificity and allows for targeted antibiotic therapy. Joint aspiration presents an important pillar to diagnose PSI.}, language = {en} } @article{MoremiClausVogeletal.2017, author = {Moremi, Nyambura and Claus, Heike and Vogel, Ulrich and Mshana, Stephen E.}, title = {Surveillance of surgical site infections by Pseudomonas aeruginosa and strain characterization in Tanzanian hospitals does not provide proof for a role of hospital water plumbing systems in transmission}, series = {Antimicrobial Resistance and Infection Control}, volume = {6}, journal = {Antimicrobial Resistance and Infection Control}, number = {56}, doi = {10.1186/s13756-017-0216-x}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-158168}, year = {2017}, abstract = {Background The role of hospital water systems in the development of Pseudomonas aeruginosa (P. aeruginosa) surgical site infections (SSIs) in low-income countries is barely studied. This study characterized P. aeruginosa isolates from patients and water in order to establish possible epidemiological links. Methods: Between December 2014 and September 2015, rectal and wound swabs, and water samples were collected in the frame of active surveillance for SSIs in the two Tanzanian hospitals. Typing of P. aeruginosa was done by multi-locus sequence typing. Results: Of 930 enrolled patients, 536 were followed up, of whom 78 (14.6\%, 95\% CI; 11.6-17.5) developed SSIs. P. aeruginosa was found in eight (14\%) of 57 investigated wounds. Of the 43 water sampling points, 29 were positive for P. aeruginosa. However, epidemiological links to wound infections were not confirmed. The P. aeruginosa carriage rate on admission was 0.9\% (8/930). Of the 363 patients re-screened upon discharge, four (1.1\%) possibly acquired P. aeruginosa during hospitalization. Wound infections of the three of the eight P. aeruginosa SSIs were caused by a strain of the same sequence type (ST) as the one from intestinal carriage. Isolates from patients were more resistant to antibiotics than water isolates. Conclusions: The P. aeruginosa SSI rate was low. There was no evidence for transmission from tap water. Not all P. aeruginosa SSI were proven to be endogenous, pointing to other routes of transmission.}, language = {en} } @article{DoranFuldeGratzetal.2016, author = {Doran, Kelly S. and Fulde, Marcus and Gratz, Nina and Kim, Brandon J. and Nau, Roland and Prasadarao, Nemani and Schubert-Unkmeir, Alexandra and Tuomanen, Elaine I. and Valentin-Weigand, Peter}, title = {Host-pathogen interactions in bacterial meningitis}, series = {Acta Neuropathologica}, volume = {131}, journal = {Acta Neuropathologica}, number = {2}, doi = {10.1007/s00401-015-1531-z}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-191034}, pages = {185-209}, year = {2016}, abstract = {Bacterial meningitis is a devastating disease occurring worldwide with up to half of the survivors left with permanent neurological sequelae. Due to intrinsic properties of the meningeal pathogens and the host responses they induce, infection can cause relatively specific lesions and clinical syndromes that result from interference with the function of the affected nervous system tissue. Pathogenesis is based on complex host-pathogen interactions, some of which are specific for certain bacteria, whereas others are shared among different pathogens. In this review, we summarize the recent progress made in understanding the molecular and cellular events involved in these interactions. We focus on selected major pathogens, Streptococcus pneumonia, S. agalactiae (Group B Streptococcus), Neisseria meningitidis, and Escherichia coli K1, and also include a neglected zoonotic pathogen, Streptococcus suis. These neuroinvasive pathogens represent common themes of host-pathogen interactions, such as colonization and invasion of mucosal barriers, survival in the blood stream, entry into the central nervous system by translocation of the blood-brain and blood-cerebrospinal fluid barrier, and induction of meningeal inflammation, affecting pia mater, the arachnoid and subarachnoid spaces.}, language = {en} } @article{HerrmannMuenstermannStrobeletal.2018, author = {Herrmann, Johannes and Muenstermann, Marcel and Strobel, Lea and Schubert-Unkmeir, Alexandra and Woodruff, Trent M. and Gray-Owen, Scott D. and Klos, Andreas and Johswich, Kay O.}, title = {Complement C5a receptor 1 exacerbates the pathophysiology of N. meningitidis sepsis and is a potential target for disease treatment}, series = {mBio}, volume = {9}, journal = {mBio}, number = {1}, doi = {10.1128/mBio.01755-17}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-175792}, pages = {e01755-17}, year = {2018}, abstract = {Sepsis caused by Neisseria meningitidis (meningococcus) is a rapidly progressing, life-threatening disease. Because its initial symptoms are rather unspecific, medical attention is often sought too late, i.e., when the systemic inflammatory response is already unleashed. This in turn limits the success of antibiotic treatment. The complement system is generally accepted as the most important innate immune determinant against invasive meningococcal disease since it protects the host through the bactericidal membrane attack complex. However, complement activation concomitantly liberates the C5a peptide, and it remains unclear whether this potent anaphylatoxin contributes to protection and/or drives the rapidly progressing immunopathogenesis associated with meningococcal disease. Here, we dissected the specific contribution of C5a receptor 1 (C5aR1), the canonical receptor for C5a, using a mouse model of meningococcal sepsis. Mice lacking C3 or C5 displayed susceptibility that was enhanced by >1,000-fold or 100-fold, respectively, consistent with the contribution of these components to protection. In clear contrast, C5ar1\(^{-/-}\) mice resisted invasive meningococcal infection and cleared N. meningitidis more rapidly than wild-type (WT) animals. This favorable outcome stemmed from an ameliorated inflammatory cytokine response to N. meningitidis in C5ar1\(^{-/-}\) mice in both in vivo and ex vivo whole-blood infections. In addition, inhibition of C5aR1 signaling without interference with the complement bactericidal activity reduced the inflammatory response also in human whole blood. Enticingly, pharmacologic C5aR1 blockade enhanced mouse survival and lowered meningococcal burden even when the treatment was administered after sepsis induction. Together, our findings demonstrate that C5aR1 drives the pathophysiology associated with meningococcal sepsis and provides a promising target for adjunctive therapy. Importance: The devastating consequences of N. meningitidis sepsis arise due to the rapidly arising and self-propagating inflammatory response that mobilizes antibacterial defenses but also drives the immunopathology associated with meningococcemia. The complement cascade provides innate broad-spectrum protection against infection by directly damaging the envelope of pathogenic microbes through the membrane attack complex and triggers an inflammatory response via the C5a peptide and its receptor C5aR1 aimed at mobilizing cellular effectors of immunity. Here, we consider the potential of separating the bactericidal activities of the complement cascade from its immune activating function to improve outcome of N. meningitidis sepsis. Our findings demonstrate that the specific genetic or pharmacological disruption of C5aR1 rapidly ameliorates disease by suppressing the pathogenic inflammatory response and, surprisingly, allows faster clearance of the bacterial infection. This outcome provides a clear demonstration of the therapeutic benefit of the use of C5aR1-specific inhibitors to improve the outcome of invasive meningococcal disease.}, language = {en} } @article{BauriedlGerovacHeidrichetal.2020, author = {Bauriedl, Saskia and Gerovac, Milan and Heidrich, Nadja and Bischler, Thorsten and Barquist, Lars and Vogel, J{\"o}rg and Schoen, Christoph}, title = {The minimal meningococcal ProQ protein has an intrinsic capacity for structure-based global RNA recognition}, series = {Nature Communications}, volume = {11}, journal = {Nature Communications}, doi = {10.1038/s41467-020-16650-6}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-230040}, year = {2020}, abstract = {FinO-domain proteins are a widespread family of bacterial RNA-binding proteins with regulatory functions. Their target spectrum ranges from a single RNA pair, in the case of plasmid-encoded FinO, to global RNA regulons, as with enterobacterial ProQ. To assess whether the FinO domain itself is intrinsically selective or promiscuous, we determine in vivo targets of Neisseria meningitidis, which consists of solely a FinO domain. UV-CLIP-seq identifies associations with 16 small non-coding sRNAs and 166 mRNAs. Meningococcal ProQ predominantly binds to highly structured regions and generally acts to stabilize its RNA targets. Loss of ProQ alters transcript levels of >250 genes, demonstrating that this minimal ProQ protein impacts gene expression globally. Phenotypic analyses indicate that ProQ promotes oxidative stress resistance and DNA damage repair. We conclude that FinO domain proteins recognize some abundant type of RNA shape and evolve RNA binding selectivity through acquisition of additional regions that constrain target recognition. FinO-domain proteins are bacterial RNA-binding proteins with a wide range of target specificities. Here, the authors employ UV CLIP-seq and show that minimal ProQ protein of Neisseria meningitidis binds to various small non-coding RNAs and mRNAs involved in virulence.}, language = {en} } @article{GomesWestermannSauerweinetal.2019, author = {Gomes, Sara F. Martins and Westermann, Alexander J. and Sauerwein, Till and Hertlein, Tobias and F{\"o}rstner, Konrad U. and Ohlsen, Knut and Metzger, Marco and Shusta, Eric V. and Kim, Brandon J. and Appelt-Menzel, Antje and Schubert-Unkmeir, Alexandra}, title = {Induced pluripotent stem cell-derived brain endothelial cells as a cellular model to study Neisseria meningitidis infection}, series = {Frontiers in Microbiology}, volume = {10}, journal = {Frontiers in Microbiology}, number = {1181}, doi = {10.3389/fmicb.2019.01181}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-201562}, year = {2019}, abstract = {Meningococcal meningitis is a severe central nervous system infection that occurs when Neisseria meningitidis (Nm) penetrates brain endothelial cells (BECs) of the meningeal blood-cerebrospinal fluid barrier. As a human-specific pathogen, in vivo models are greatly limited and pose a significant challenge. In vitro cell models have been developed, however, most lack critical BEC phenotypes limiting their usefulness. Human BECs generated from induced pluripotent stem cells (iPSCs) retain BEC properties and offer the prospect of modeling the human-specific Nm interaction with BECs. Here, we exploit iPSC-BECs as a novel cellular model to study Nm host-pathogen interactions, and provide an overview of host responses to Nm infection. Using iPSC-BECs, we first confirmed that multiple Nm strains and mutants follow similar phenotypes to previously described models. The recruitment of the recently published pilus adhesin receptor CD147 underneath meningococcal microcolonies could be verified in iPSC-BECs. Nm was also observed to significantly increase the expression of pro-inflammatory and neutrophil-specific chemokines IL6, CXCL1, CXCL2, CXCL8, and CCL20, and the secretion of IFN-γ and RANTES. For the first time, we directly observe that Nm disrupts the three tight junction proteins ZO-1, Occludin, and Claudin-5, which become frayed and/or discontinuous in BECs upon Nm challenge. In accordance with tight junction loss, a sharp loss in trans-endothelial electrical resistance, and an increase in sodium fluorescein permeability and in bacterial transmigration, was observed. Finally, we established RNA-Seq of sorted, infected iPSC-BECs, providing expression data of Nm-responsive host genes. Altogether, this model provides novel insights into Nm pathogenesis, including an impact of Nm on barrier properties and tight junction complexes, and suggests that the paracellular route may contribute to Nm traversal of BECs.}, language = {en} } @phdthesis{Peters2021, author = {Peters, Simon}, title = {The impact of sphingolipids on \(Neisseria\) \(meningitidis\) and their role in meningococcal pathogenicity}, doi = {10.25972/OPUS-22623}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-226233}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2021}, abstract = {The obligate human pathogen Neisseria meningitidis is a major cause of sepsis and meningitis worldwide. It affects mainly toddlers and infants and is responsible for thousands of deaths each year. In this study, different aspects of the importance of sphingolipids in meningococcal pathogenicity were investigated. In a first step, the acid sphingomyelinase (ASM), which degrades membrane sphingomyelin to ceramide, was studied in the context of meningococcal infection. A requirement for ASM surface activity is its translocation from the lysosomal compartment to the cell surface, a process that is currently poorly understood. This study used various approaches, including classical invasion and adherence assays, flow cytometry, and classical and super resolution immunofluorescence microscopy (dSTORM). The results showed that the live, highly piliated N. meningitidis strain 8013/12 induced calcium-dependent ASM translocation in human brain microvascular endothelial cells (HBMEC). Furthermore, it promoted the formation of ceramide-rich platforms (CRPs). In addition, ASM translocation and CRP formation were observed after treating the cells with pili-enriched fractions derived from the same strain. The importance for N. meningitidis to utilize this pathway was shown by the inhibition of the calcium-dependent ASM translocation, which greatly decreased the number of invasive bacteria. I also investigated the importance of the glycosphingolipids GM1 and Gb3. The results showed that GM1, but not Gb3, plays an important role in the ability of N. meningitidis to invade HBMEC. By combining dSTORM imaging and microbiological approaches, we demonstrated that GM1 accumulated prolifically around bacteria during the infection, and that this interaction seemed essential for meningococcal invasion. Sphingolipids are not only known for their beneficial effect on pathogens. Sphingoid bases, including sphingosine, are known for their antimicrobial activity. In the last part of this study, a novel correlative light and electron microscopy approach was established in the combination with click chemistry to precisely localize azido-functionalized sphingolipids in N. meningitidis. The result showed a distinct concentration-dependent localization in either the outer membrane (low concentration) or accumulated in the cytosol (high concentration). This pattern was confirmed by mass spectrometry on separated membrane fractions. Our data provide a first insight into the underlying mechanism of antimicrobial sphingolipids.}, subject = {Neisseria meningitidis}, language = {en} } @phdthesis{Bauriedl2020, author = {Bauriedl, Saskia Corinna}, title = {The influence of riboregulation on fitness and virulence in Neisseria meningitidis}, doi = {10.25972/OPUS-19297}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-192978}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2020}, abstract = {Neisseria meningitidis (N. meningitidis) is a human commensal that occasionally causes life-threatening infections such as bacterial meningitis and septicemia. Despite experi-mental evidence that the expression of small non-coding RNAs (sRNAs) as well as the RNA chaperone Hfq affect meningococcal physiology, the impact of RNA-based regula-tion (riboregulation) on fitness and virulence in N. meningitidis is only poorly understood. Therefore, this study addressed these issues using a combination of high-throughput tech-nologies. A differential RNA-sequencing (dRNA-seq) approach was applied to produce a single-nucleotide resolution map of the primary transcriptome of N. meningitidis strain 8013. The dRNA-seq analysis predicted 1,625 transcriptional start sites including 65 putative sRNAs, of which 20 were further validated by northern blot analysis. By Hfq RNA im-munopreci-pitation sequencing a large Hfq-centered post-transcriptional regulatory net-work comprising 23 sRNAs and 401 potential mRNA targets was identified. Rifampicin stability assays demonstrated that Hfq binding confers enhanced stability on its associat-ed sRNAs. Based on these data, the interactions of two paralogous sRNAs and their cog-nate target mRNA prpB were validated in vivo as well as in vitro. Both sRNAs directly repress prpB encoding a methylisocitrate lyse which was previously shown to be involved in meningococcal colonization of the human nasopharynx. Besides the well-described RNA chaperone Hfq, FinO-domain proteins have recently been recognized as a widespread family of RNA-binding proteins (RBPs) with regulatory roles in diverse bacteria. They display an intriguing bandwidth of target sites, ranging from a single RNA pair as recognized by plasmid-encoded FinO to the global RNA regu-lons of enterobacterial ProQ proteins. To better understand the intrinsic targeting mode of this RBP family, in vivo targets of the minimal ProQ protein of N. meningitidis were de-termined. In vivo UV crosslinking with RNA deep sequencing (UV-CLIP) identified as-sociations of ProQ with 16 sRNAs and 166 mRNAs encoding a variety of biological functions and thus revealed ProQ as another global RBP in meningococci. It could be shown that meningococcal ProQ predominantly binds to highly structured RNA regions including DNA uptake sequences (DUS) and rho-independent transcription terminators and stabilizes many of its RNA targets as proved by rifampicin stability experiments. As expected from the large suite of ProQ-bound RNAs, proQ deletion globally affects both gene and protein expression in N. meningitidis, changing the expression levels of at least 244 mRNAs and 80 proteins. Phenotypic analyses suggested that ProQ promotes oxida-tive stress tolerance and UV damage repair capacity, both of which are required for full virulence of N. meningitidis. Together, this work uncovers the co-existence of two major post-transcriptional regulons, one governed by ProQ, the other by Hfq, in N. meningitidis. It further highlights the role of these distinct RBPs and its associated sRNAs to bacterial virulence and indicates that riboregulation is likely to contribute to the way how meningococci adapt to different host niches.}, subject = {Neisseria meningitidis}, language = {en} } @article{EndresJungblutDivyapicigiletal.2022, author = {Endres, Leo M. and Jungblut, Marvin and Divyapicigil, Mustafa and Sauer, Markus and Stigloher, Christian and Christodoulides, Myron and Kim, Brandon J. and Schubert-Unkmeir, Alexandra}, title = {Development of a multicellular in vitro model of the meningeal blood-CSF barrier to study Neisseria meningitidis infection}, series = {Fluids and Barriers of the CNS}, volume = {19}, journal = {Fluids and Barriers of the CNS}, number = {1}, doi = {10.1186/s12987-022-00379-z}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-300208}, year = {2022}, abstract = {Background Bacterial meningitis is a life-threatening disease that occurs when pathogens such as Neisseria meningitidis cross the meningeal blood cerebrospinal fluid barrier (mBCSFB) and infect the meninges. Due to the human-specific nature of N. meningitidis, previous research investigating this complex host-pathogen interaction has mostly been done in vitro using immortalized brain endothelial cells (BECs) alone, which often do not retain relevant barrier properties in culture. Here, we developed physiologically relevant mBCSFB models using BECs in co-culture with leptomeningeal cells (LMCs) to examine N. meningitidis interaction. Methods We used BEC-like cells derived from induced pluripotent stem cells (iBECs) or hCMEC/D3 cells in co-culture with LMCs derived from tumor biopsies. We employed TEM and structured illumination microscopy to characterize the models as well as bacterial interaction. We measured TEER and sodium fluorescein (NaF) permeability to determine barrier tightness and integrity. We then analyzed bacterial adherence and penetration of the cell barrier and examined changes in host gene expression of tight junctions as well as chemokines and cytokines in response to infection. Results Both cell types remained distinct in co-culture and iBECs showed characteristic expression of BEC markers including tight junction proteins and endothelial markers. iBEC barrier function as determined by TEER and NaF permeability was improved by LMC co-culture and remained stable for seven days. BEC response to N. meningitidis infection was not affected by LMC co-culture. We detected considerable amounts of BEC-adherent meningococci and a relatively small number of intracellular bacteria. Interestingly, we discovered bacteria traversing the BEC-LMC barrier within the first 24 h post-infection, when barrier integrity was still high, suggesting a transcellular route for N. meningitidis into the CNS. Finally, we observed deterioration of barrier properties including loss of TEER and reduced expression of cell-junction components at late time points of infection. Conclusions Here, we report, for the first time, on co-culture of human iPSC derived BECs or hCMEC/D3 with meningioma derived LMCs and find that LMC co-culture improves barrier properties of iBECs. These novel models allow for a better understanding of N. meningitidis interaction at the mBCSFB in a physiologically relevant setting.}, language = {en} } @article{ForsterKohlmorgenHaasetal.2022, author = {Forster, Johannes and Kohlmorgen, Britta and Haas, Julian and Weis, Philipp and Breunig, Lukas and Turnwald, Doris and Mizaikoff, Boris and Schoen, Christoph}, title = {A streamlined method for the fast and cost-effective detection of bacterial pathogens from positive blood cultures for the BacT/ALERT blood culture system using the Vitek MS mass spectrometer}, series = {PLoS ONE}, volume = {17}, journal = {PLoS ONE}, number = {4}, doi = {10.1371/journal.pone.0267669}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-300213}, year = {2022}, abstract = {Background and objective Prompt pathogen identification of blood stream infections is essential to provide appropriate antibiotic treatment. Therefore, the objective of this prospective single centre study was to establish an inexpensive, fast and accurate protocol for bacterial species identification with SDS protein-extraction directly from BacT/Alert® blood culture (BC) bottles by VitekMS®. Results Correct species identification was obtained for 198/266 (74.4\%, 95\%-CI = [68.8\%, 79.6\%]) of pathogens. The protocol was more successful in identifying 87/96 (91.4\%, 95\%-CI = [83.8\%, 93.2\%]) gram-negative bacteria than 110/167 (65.9\%, 95\%-CI = [58.1\%, 73.0\%]) gram-positive bacteria. The hands-on time for sample preparation and measurement was about 15 min for up to five samples. This is shorter than for most other protocols using a similar lysis-centrifugation approach for the combination of BacT/Alert® BC bottles and the Vitek® MS mass spectrometer. The estimated costs per sample were approx. 1.80€ which is much cheaper than for commercial kits. Conclusion This optimized protocol allows for accurate identification of bacteria directly from blood culture bottles for laboratories equipped with BacT/Alert® blood culture bottles and VitekMS® mass spectrometer.}, language = {en} } @article{MuenstermannStrobelKlosetal.2019, author = {Muenstermann, Marcel and Strobel, Lea and Klos, Andreas and Wetsel, Rick A. and Woodruff, Trent M. and K{\"o}hl, J{\"o}rg and Johswich, Kay O.}, title = {Distinct roles of the anaphylatoxin receptors C3aR, C5aR1 and C5aR2 in experimental meningococcal infections}, series = {Virulence}, volume = {10}, journal = {Virulence}, number = {1}, doi = {10.1080/21505594.2019.1640035}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-200496}, pages = {677-694}, year = {2019}, abstract = {The complement system is pivotal in the defense against invasive disease caused by Neisseria meningitidis (Nme, meningococcus), particularly via the membrane attack complex. Complement activation liberates the anaphylatoxins C3a and C5a, which activate three distinct G-protein coupled receptors, C3aR, C5aR1 and C5aR2 (anaphylatoxin receptors, ATRs). We recently discovered that C5aR1 exacerbates the course of the disease, revealing a downside of complement in Nme sepsis. Here, we compared the roles of all three ATRs during mouse nasal colonization, intraperitoneal infection and human whole blood infection with Nme. Deficiency of complement or ATRs did not alter nasal colonization, but significantly affected invasive disease: Compared to WT mice, the disease was aggravated in C3ar\(^{-/-}\) mice, whereas C5ar1\(^{-/-}\) and C5ar2\(^{-/-}\) mice showed increased resistance to meningococcal sepsis. Surprisingly, deletion of either of the ATRs resulted in lower cytokine/chemokine responses, irrespective of the different susceptibilities of the mice. This was similar in ex vivo human whole blood infection using ATR inhibitors. Neutrophil responses to Nme were reduced in C5ar1\(^{-/-}\) mouse blood. Upon stimulation with C5a plus Nme, mouse macrophages displayed reduced phosphorylation of ERK1/2, when C5aR1 or C5aR2 were ablated or inhibited, suggesting that both C5a-receptors prime an initial macrophage response to Nme. Finally, in vivo blockade of C5aR1 alone (PMX205) or along with C5aR2 (A8\(^{Δ71-73}\)) resulted in ameliorated disease, whereas neither antagonizing C3aR (SB290157) nor its activation with a "super-agonist" peptide (WWGKKYRASKLGLAR) demonstrated a benefit. Thus, C5aR1 and C5aR2 augment disease pathology and are interesting targets for treatment, whereas C3aR is protective in experimental meningococcal sepsis.}, language = {en} } @article{WurmbScholtesKolibayetal.2020, author = {Wurmb, Thomas and Scholtes, Katja and Kolibay, Felix and Schorscher, Nora and Ertl, Georg and Ernestus, Ralf-Ingo and Vogel, Ulrich and Franke, Axel and Kowalzik, Barbara}, title = {Hospital preparedness for mass critical care during SARS-CoV-2 pandemic}, series = {Critical Care}, volume = {24}, journal = {Critical Care}, doi = {10.1186/s13054-020-03104-0}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-230201}, year = {2020}, abstract = {Mass critical care caused by the severe acute respiratory syndrome corona virus 2 pandemic poses an extreme challenge to hospitals. The primary goal of hospital disaster preparedness and response is to maintain conventional or contingency care for as long as possible. Crisis care must be delayed as long as possible by appropriate measures. Increasing the intensive care unit (ICU) capacities is essential. In order to adjust surge capacity, the reduction of planned, elective patient care is an adequate response. However, this involves numerous problems that must be solved with a sense of proportion. This paper summarises preparedness and response measures recommended to acute care hospitals.}, language = {en} } @article{PetersKaiserFinketal.2021, author = {Peters, Simon and Kaiser, Lena and Fink, Julian and Schumacher, Fabian and Perschin, Veronika and Schlegel, Jan and Sauer, Markus and Stigloher, Christian and Kleuser, Burkhard and Seibel, Juergen and Schubert-Unkmeir, Alexandra}, title = {Click-correlative light and electron microscopy (click-AT-CLEM) for imaging and tracking azido-functionalized sphingolipids in bacteria}, series = {Scientific Reports}, volume = {11}, journal = {Scientific Reports}, number = {1}, doi = {10.1038/s41598-021-83813-w}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-259147}, pages = {4300}, year = {2021}, abstract = {Sphingolipids, including ceramides, are a diverse group of structurally related lipids composed of a sphingoid base backbone coupled to a fatty acid side chain and modified terminal hydroxyl group. Recently, it has been shown that sphingolipids show antimicrobial activity against a broad range of pathogenic microorganisms. The antimicrobial mechanism, however, remains so far elusive. Here, we introduce 'click-AT-CLEM', a labeling technique for correlated light and electron microscopy (CLEM) based on the super-resolution array tomography (srAT) approach and bio-orthogonal click chemistry for imaging of azido-tagged sphingolipids to directly visualize their interaction with the model Gram-negative bacterium Neisseria meningitidis at subcellular level. We observed ultrastructural damage of bacteria and disruption of the bacterial outer membrane induced by two azido-modified sphingolipids by scanning electron microscopy and transmission electron microscopy. Click-AT-CLEM imaging and mass spectrometry clearly revealed efficient incorporation of azido-tagged sphingolipids into the outer membrane of Gram-negative bacteria as underlying cause of their antimicrobial activity.}, language = {en} } @article{SilwedelSpeerHaarmannetal.2018, author = {Silwedel, Christine and Speer, Christian P. and Haarmann, Axel and Fehrholz, Markus and Claus, Heike and Buttmann, Mathias and Glaser, Kirsten}, title = {Novel insights into neuroinflammation: bacterial lipopolysaccharide, tumor necrosis factor α, and Ureaplasma species differentially modulate atypical chemokine receptor 3 responses in human brain microvascular endothelial cells}, series = {Journal of Neuroinflammation}, volume = {15}, journal = {Journal of Neuroinflammation}, number = {156}, doi = {10.1186/s12974-018-1170-0}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-175952}, year = {2018}, abstract = {Background: Atypical chemokine receptor 3 (ACKR3, synonym CXCR7) is increasingly considered relevant in neuroinflammatory conditions, in which its upregulation contributes to compromised endothelial barrier function and may ultimately allow inflammatory brain injury. While an impact of ACKR3 has been recognized in several neurological autoimmune diseases, neuroinflammation may also result from infectious agents, including Ureaplasma species (spp.). Although commonly regarded as commensals of the adult urogenital tract, Ureaplasma spp. may cause invasive infections in immunocompromised adults as well as in neonates and appear to be relevant pathogens in neonatal meningitis. Nonetheless, clinical and in vitro data on Ureaplasma-induced inflammation are scarce. Methods: We established a cell culture model of Ureaplasma meningitis, aiming to analyze ACKR3 variances as a possible pathomechanism in Ureaplasma-associated neuroinflammation. Non-immortalized human brain microvascular endothelial cells (HBMEC) were exposed to bacterial lipopolysaccharide (LPS) or tumor necrosis factor-α (TNF-α), and native as well as LPS-primed HBMEC were cultured with Ureaplasma urealyticum serovar 8 (Uu8) and U. parvum serovar 3 (Up3). ACKR3 responses were assessed via qRT-PCR, RNA sequencing, flow cytometry, and immunocytochemistry. Results: LPS, TNF-α, and Ureaplasma spp. influenced ACKR3 expression in HBMEC. LPS and TNF-α significantly induced ACKR3 mRNA expression (p < 0.001, vs. control), whereas Ureaplasma spp. enhanced ACKR3 protein expression in HBMEC (p < 0.01, vs. broth control). Co-stimulation with LPS and either Ureaplasma isolate intensified ACKR3 responses (p < 0.05, vs. LPS). Furthermore, stimulation wielded a differential influence on the receptor's ligands. Conclusions: We introduce an in vitro model of Ureaplasma meningitis. We are able to demonstrate a pro-inflammatory capacity of Ureaplasma spp. in native and, even more so, in LPS-primed HBMEC, underlining their clinical relevance particularly in a setting of co-infection. Furthermore, our data may indicate a novel role for ACKR3, with an impact not limited to auto-inflammatory diseases, but extending to infection-related neuroinflammation as well. AKCR3-induced blood-brain barrier breakdown might constitute a potential common pathomechanism.}, language = {en} } @article{StrobelJohswich2018, author = {Strobel, Lea and Johswich, Kay O.}, title = {Anticoagulants impact on innate immune responses and bacterial survival in whole blood models of Neisseria meningitidis infection}, series = {Scientific Reports}, volume = {8}, journal = {Scientific Reports}, number = {10225}, doi = {10.1038/s41598-018-28583-8}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-176226}, year = {2018}, abstract = {Neisseria meningitidis (meningococcus) causes invasive diseases such as meningitis or septicaemia. Ex vivo infection of human whole blood is a valuable tool to study meningococcal virulence factors and the host innate immune responses. In order to consider effects of cellular mediators, the coagulation cascade must be inhibited to avoid clotting. There is considerable variation in the anticoagulants used among studies of N. meningitidis whole blood infections, featuring citrate, heparin or derivatives of hirudin, a polypeptide from leech saliva. Here, we compare the influence of these three different anticoagulants, and additionally Mg/EGTA, on host innate immune responses as well as on viability of N. meningitidis strains isolated from healthy carriers and disease cases, reflecting different sequence types and capsule phenotypes. We found that the anticoagulants significantly impact on cellular responses and, strain-dependently, also on bacterial survival. Hirudin does not inhibit complement and is therefore superior over the other anticoagulants; indeed hirudin-plasma most closely reflects the characteristics of serum during N. meningitidis infection. We further demonstrate the impact of heparin on complement activation on N. meningitidis and its consequences on meningococcal survival in immune sera, which appears to be independent of the heparin binding antigens Opc and NHBA.}, language = {en} } @article{GoetzPanzerTrinksetal.2020, author = {G{\"o}tz, Ralph and Panzer, Sabine and Trinks, Nora and Eilts, Janna and Wagener, Johannes and Turr{\`a}, David and Di Pietro, Antonio and Sauer, Markus and Terpitz, Ulrich}, title = {Expansion Microscopy for Cell Biology Analysis in Fungi}, series = {Frontiers in Microbiology}, volume = {11}, journal = {Frontiers in Microbiology}, issn = {1664-302X}, doi = {10.3389/fmicb.2020.00574}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-202569}, year = {2020}, abstract = {Super-resolution microscopy has evolved as a powerful method for subdiffraction-resolution fluorescence imaging of cells and cellular organelles, but requires sophisticated and expensive installations. Expansion microscopy (ExM), which is based on the physical expansion of the cellular structure of interest, provides a cheap alternative to bypass the diffraction limit and enable super-resolution imaging on a conventional fluorescence microscope. While ExM has shown impressive results for the magnified visualization of proteins and RNAs in cells and tissues, it has not yet been applied in fungi, mainly due to their complex cell wall. Here we developed a method that enables reliable isotropic expansion of ascomycetes and basidiomycetes upon treatment with cell wall degrading enzymes. Confocal laser scanning microscopy (CLSM) and structured illumination microscopy (SIM) images of 4.5-fold expanded sporidia of Ustilago maydis expressing fluorescent fungal rhodopsins and hyphae of Fusarium oxysporum or Aspergillus fumigatus expressing either histone H1-mCherry together with Lifeact-sGFP or mRFP targeted to mitochondria, revealed details of subcellular structures with an estimated spatial resolution of around 30 nm. ExM is thus well suited for cell biology studies in fungi on conventional fluorescence microscopes.}, language = {en} } @article{ForsterDichtlWagener2022, author = {Forster, Johannes and Dichtl, Karl and Wagener, Johannes}, title = {Lower beta-1,3-D-glucan testing cut-offs increase sensitivity for non-albicans Candida species bloodstream infections}, series = {Mycoses}, volume = {65}, journal = {Mycoses}, number = {5}, doi = {10.1111/myc.13421}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-276515}, pages = {500 -- 507}, year = {2022}, abstract = {Purpose Fungal biomarkers support early diagnosis of invasive fungal infections. In this study, we evaluated the impact of a recent update to the manufacturer-recommended cut-off for beta-1,3-D-glucan (BDG) testing (Fujifilm Wako BDG assay) on sensitivity and specificity for the detection of candidemia. Additionally, we compared the performance with tests for Candida antigen (Ag by Serion ELISA antigen Candida, Virion\Serion) and anti-mannan antibodies (Ab by Hemkit Candida IHA, Ravo Diagnostika). Methods Sera of 82 patients with candidemia, which were sampled with a maximum distance of ±14 days from the date of sampling of the corresponding positive blood cultures, were retrospectively analysed for BDG, Ag and Ab. Results of BDG testing were compared with results from sera of 129 patients with candidemia from a different hospital. Results Sensitivity of BDG testing (47\%) was higher than for Ag (17\%) or Ab (20\%). By combining Ag and Ab testing, sensitivity was raised to 32\%. Lowering the cut-off of BDG from 11 pg/ml to the newly recommended cut-off of 7 pg/ml resulted in a significant increase in sensitivity (47\% vs 58\%, p = .01 and 63\% vs 71\% p < .01). At both centres, the increase was significant in NAC but not in C. albicans candidemia. No significant effects on specificity were observed. Conclusion BDG testing outperformed Ag and Ab testing and its combination. Lowering the BDG cut-off had no significant impact on specificity. The increase in sensitivity can be mainly attributed to a gain in sensitivity for non-albicans Candida species bloodstream infections.}, language = {en} } @phdthesis{Herrmann2023, author = {Herrmann, Ruth Magdalena}, title = {Molekular- und zellbiologische Untersuchung zur Rolle des kanonischen Wnt-Signalwegs bei der Entwicklung von \(Echinococcus\) \(multilocularis\)}, doi = {10.25972/OPUS-27193}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-271937}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2023}, abstract = {Die alveol{\"a}re Echinokokkose (AE) ist eine lebensbedrohliche Erkrankung des Menschen, welche durch das infiltrative Wachstum des Metazestoden-Larvenstadiums des Fuchsbandwurms (Echinococcus multilocularis) in der Leber verursacht wird. Das tumorartige Wachstum des Metazestoden beruht auf einer Echinococcus-spezifischen Modifikation der anterior-posterioren-K{\"o}rperachse (AP Achse). Es wird vermutet, dass dabei der anteriore Pol der invadierenden Oncosp{\"a}ren-Larve zun{\"a}chst abgeschaltet wird und sich der Metazestode anschließend asexuell als vesikul{\"a}res, posteriorisiertes Gewebes im Wirt vermehrt. Nach massiver Proliferation wird der anteriore Pol reetabliert und f{\"u}hrt zur Bildung zahlreicher Bandwurm-Kopfanlagen (Protoskolizes). Da die Ausbildung der AP K{\"o}rperachse evolutionsgeschichtlich konserviert {\"u}ber den wingless-related (Wnt)-Signalweg gesteuert wird, wurde in dieser Arbeit die Rolle von Wnt-Signaling bei der Musterbildung von E. multilocularis {\"u}ber molekular- und zellbiologische Studien n{\"a}her beleuchtet. Zentraler methodischer Ansatz der vorliegenden Arbeit war ein E. multilocularis Stammzell-Kultursystem, das Prim{\"a}rzellsystem, welches die in vitro-Generierung von Metazestoden-Vesikeln durch Proliferation und Differenzierung von germinativen Zellen (Stammzellen) erlaubt. {\"U}ber RNA-Sequenzierung wurde zun{\"a}chst gezeigt, dass in Prim{\"a}rzellkulturen sowohl Markergene f{\"u}r posteriore Entwicklung in Richtung Metazestode wie auch f{\"u}r Anterior-und Protoskolexmarker exprimiert werden. Unter Verwendung von RNA-Interferenz (RNAi) wurde anschließend ein erfolgreicher Knockdown des vermuteten Hauptregulators des kanonischen Wnt-Signalwegs, β Catenin (em-bcat1), erreicht und f{\"u}hrte zu einem charakteristischen, sogenannten ‚red dot' Ph{\"a}notyp, dem ersten jemals beschriebenen RNAi Ph{\"a}notyp f{\"u}r E. multilocularis-Prim{\"a}rzellen. Prim{\"a}rzellkulturen nach em-bcat1 RNAi zeigten eine stark verminderte F{\"a}higkeit, Metazestoden-Vesikel zu bilden sowie eine {\"U}berproliferation von germinativen Zellen. Zus{\"a}tzliche RNA-Seq-Analysen des Transkriptoms von RNAi(em-bcat1)-Kulturen zeigten eine signifikant verringerte Expression von Posterior- und Metazestodenmarkern, w{\"a}hrend Anterior- und Protoskolexmarker deutlich {\"u}berexprimiert wurden. Durch umfangreiche Whole-mount-in-situ-Hybridisierung (WMISH)-Experimente wurden diese Daten f{\"u}r eine Reihe ausgew{\"a}hlter Markergene f{\"u}r posteriore (Metazestode; em-wnt1, em-wnt11b, em-muc1) und f{\"u}r anteriore Entwicklung (Protoskolex; em sfrp, em-nou-darake, em npp36, em-frizzled10) verifiziert. In allen genannten F{\"a}llen zeigte sich durch {\"A}nderung der Polarit{\"a}t eine verminderte Genexpression von Posteriormarkern, w{\"a}hrend Anteriormarker deutlich erh{\"o}ht exprimiert wurden. {\"A}hnlich wie bei den verwandten, freilebenden Planarien, f{\"u}hrt demnach ein Knockdown des zentralen Wnt-Regulators β-Catenin bei E. multilocularis zu einer anteriorisierten, Anterior- und Protoskolexmarker dominierte Genexpression, welche der posteriorisierten Entwicklung zum Metazestoden entgegenwirkt. Neben Markergenen f{\"u}r die Ausbildung der AP-Achse wurden in dieser Arbeit auch solche f{\"u}r die medio-laterale (ML)-K{\"o}rperachse bei Zestoden erstmals beschrieben. So zeigte sich, dass ein Slit-Ortholog (em slit) im E. multilocularis Protoskolex im Bereich der K{\"o}rper-Mittellinie exprimiert wird und lieferte Hinweise darauf, dass, {\"a}hnlich zur Situation bei Planarien, die ML Achse von E. multilocularis durch Morphogengradienten aus slit (Mittellinie) und wnt5 (lateral) definiert wird. Im Metazestoden wird hingegen nur em-slit exprimiert. Der Metazestode besitzt damit als posterior-medianisiertes Gewebe Anlagen zur Polarit{\"a}t zur AP- und ML-Achse, welche erst mit Bildung von Protoskolizes vollst{\"a}ndig etabliert werden. Schließlich deuten die Ergebnisse dieser Arbeit darauf hin, dass bei der Wiederherstellung der K{\"o}rperachsen w{\"a}hrend der Entwicklung von Protoskolizes Hedgehog (Hh)-Signale entscheidend mitwirken. Zusammenfassend wurde in dieser Arbeit der zentrale Faktor des kanonischen Wnt Signalwegs, β-Catenin, als Hauptregulator der Entwicklung des tumorartig wachsenden E. multilocularis-Metazestoden identifiziert. Zudem wurde gezeigt, dass zur Metazestodenbildung neben einer Echinococcus-spezifischen Modifikation der AP K{\"o}rperachse auch eine solche der ML Achse beitr{\"a}gt. In humanen malignen Tumoren sind der Wnt-, Slit-Robo- und Hh-Signalweg gut erforschte Wirkstofftargets und k{\"o}nnten in Zukunft in {\"a}hnlicher Weise f{\"u}r eine zielgerichtete Therapie von AE dienen.}, subject = {Fuchsbandwurm}, language = {de} } @article{HerzBrehm2019, author = {Herz, Michaela and Brehm, Klaus}, title = {Evidence for densovirus integrations into tapeworm genomes}, series = {Parasites \& Vectors}, volume = {12}, journal = {Parasites \& Vectors}, doi = {10.1186/s13071-019-3820-1}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-202478}, pages = {560}, year = {2019}, abstract = {Background Tapeworms lack a canonical piRNA-pathway, raising the question of how they can silence existing mobile genetic elements (MGE). Investigation towards the underlying mechanisms requires information on tapeworm transposons which is, however, presently scarce. Methods The presence of densovirus-related sequences in tapeworm genomes was studied by bioinformatic approaches. Available RNA-Seq datasets were mapped against the Echinococcus multilocularis genome to calculate expression levels of densovirus-related genes. Transcription of densovirus loci was further analyzed by sequencing and RT-qPCR. Results We herein provide evidence for the presence of densovirus-related elements in a variety of tapeworm genomes. In the high-quality genome of E. multilocularis we identified more than 20 individual densovirus integration loci which contain the information for non-structural and structural virus proteins. The majority of densovirus loci are present as head-to-tail concatemers in isolated repeat containing regions of the genome. In some cases, unique densovirus loci have integrated close to histone gene clusters. We show that some of the densovirus loci of E. multilocularis are actively transcribed, whereas the majority are transcriptionally silent. RT-qPCR data further indicate that densovirus expression mainly occurs in the E. multilocularis stem cell population, which probably forms the germline of this organism. Sequences similar to the non-structural densovirus genes present in E. multilocularis were also identified in the genomes of E. canadensis, E. granulosus, Hydatigera taeniaeformis, Hymenolepis diminuta, Hymenolepis microstoma, Hymenolepis nana, Taenia asiatica, Taenia multiceps, Taenia saginata and Taenia solium. Conclusions Our data indicate that densovirus integration has occurred in many tapeworm species. This is the first report on widespread integration of DNA viruses into cestode genomes. Since only few densovirus integration sites were transcriptionally active in E. multilocularis, our data are relevant for future studies into gene silencing mechanisms in tapeworms. Furthermore, they indicate that densovirus-based vectors might be suitable tools for genetic manipulation of cestodes.}, language = {en} } @phdthesis{Aldejohann2022, author = {Aldejohann, Alexander Maximilian}, title = {Echinocandin-Resistenzen in \(Candida\) \(glabrata\)}, doi = {10.25972/OPUS-27584}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-275840}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2022}, abstract = {Candida glabrata ist die zweith{\"a}ufigste Ursache von Candid{\"a}mien und invasiven Hefepilzinfektionen in Europa. Im Gegensatz zu C. albicans zeigt C. glabrata eine reduzierte Empfindlichkeit gegen bestimmte Antimykotika und kann unter Therapie rasch Resistenzen entwickeln. Diese Arbeit umfasst eine systematische geno- und ph{\"a}notypische Resistenzanalyse einer der gr{\"o}ßten europ{\"a}ischen - durch das NRZMyk in 5 Jahren zusammengetragenen - C. glabrata Stammsammlungen bestehend aus 176 klinisch relevanter Isolate. 84 der St{\"a}mme wurden anhand Referenztestung nach EUCAST zun{\"a}chst als Anidulafungin (AND) resistent eingestuft. 71 wiesen konkordante Mutationen in den f{\"u}r die Glucan-Synthetase kodierenden FKS-Genen auf (13 \% in FKS1, 87 \% in FKS2). Vor allem die Position Ser-663 (FKS2-HS1) imponierte mit signifikant erh{\"o}hten AND MHK-Werten. 11 FKS-Wildtyp-Isolate, die urspr{\"u}nglich als AND resistent klassifiziert wurden, wiesen in multiplen Nachtestungen um den Breakpoint undulierende AND MHK-Werte auf. 2 FKS-Wildtyp Isolate zeigten durchg{\"a}ngig hohe AND MHK-Werte und mussten daher - trotz fehlender Zielgenmutationen - als resistent eingestuft werden. Diese extremen Ph{\"a}notypen wurden durch einen verblindeten nationalen Ringversuch best{\"a}tigt. {\"U}ber ein Drittel der Isolate war multiresistent. St{\"a}mme aus Blutstrominfektionen und Ser-663 Mutation waren mit einer erh{\"o}hten Mortalit{\"a}t assoziiert. Ein weiteres Kernelement war die Detektion von Azol-resistenten C. glabrata petite-Ph{\"a}notypen in der Routinediagnostik. Hier wurden innerhalb von 8 Monaten 20 relevante Isolate identifiziert. Die Ergebnisse belegen das regelm{\"a}ßige Auftreten single- / multidrug-resistenter C. glabrata Isolate in Deutschland. Ph{\"a}notypische Resistenztestungen k{\"o}nnen zu Fehlklassifizierung von sensiblen Isolaten f{\"u}hren. FKS-Genotypisierungen hingegen sind ein n{\"u}tzliches Tool zur Identifizierung relevanter Resistenzen. In seltenen F{\"a}llen scheint jedoch eine Echinocandin-Resistenz ohne genotypisches Korrelat m{\"o}glich zu sein.}, subject = {Resistenzbestimmung}, language = {de} } @article{KimMcDonaghDengetal.2019, author = {Kim, Brandon J. and McDonagh, Maura A. and Deng, Liwen and Gastfriend, Benjamin D. and Schubert-Unkmeir, Alexandra and Doran, Kelly S. and Shusta, Eric V.}, title = {Streptococcus agalactiae disrupts P-glycoprotein function in brain endothelial cells}, series = {Fluids and Barriers of the CNS}, volume = {16}, journal = {Fluids and Barriers of the CNS}, doi = {10.1186/s12987-019-0146-5}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-201895}, pages = {26}, year = {2019}, abstract = {Bacterial meningitis is a serious life threatening infection of the CNS. To cause meningitis, blood-borne bacteria need to interact with and penetrate brain endothelial cells (BECs) that comprise the blood-brain barrier. BECs help maintain brain homeostasis and they possess an array of efflux transporters, such as P-glycoprotein (P-gp), that function to efflux potentially harmful compounds from the CNS back into the circulation. Oftentimes, efflux also serves to limit the brain uptake of therapeutic drugs, representing a major hurdle for CNS drug delivery. During meningitis, BEC barrier integrity is compromised; however, little is known about efflux transport perturbations during infection. Thus, understanding the impact of bacterial infection on P-gp function would be important for potential routes of therapeutic intervention. To this end, the meningeal bacterial pathogen, Streptococcus agalactiae, was found to inhibit P-gp activity in human induced pluripotent stem cell-derived BECs, and live bacteria were required for the observed inhibition. This observation was correlated to decreased P-gp expression both in vitro and during infection in vivo using a mouse model of bacterial meningitis. Given the impact of bacterial interactions on P-gp function, it will be important to incorporate these findings into analyses of drug delivery paradigms for bacterial infections of the CNS.}, language = {en} } @article{SoundararajanMarincolaLiongetal.2023, author = {Soundararajan, Manonmani and Marincola, Gabriella and Liong, Olivia and Marciniak, Tessa and Wencker, Freya D. R. and Hofmann, Franka and Schollenbruch, Hannah and Kobusch, Iris and Linnemann, Sabrina and Wolf, Silver A. and Helal, Mustafa and Semmler, Torsten and Walther, Birgit and Schoen, Christoph and Nyasinga, Justin and Revathi, Gunturu and Boelhauve, Marc and Ziebuhr, Wilma}, title = {Farming practice influences antimicrobial resistance burden of non-aureus staphylococci in pig husbandries}, series = {Microorganisms}, volume = {11}, journal = {Microorganisms}, number = {1}, issn = {2076-2607}, doi = {10.3390/microorganisms11010031}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-312750}, year = {2023}, abstract = {Non-aureus staphylococci (NAS) are ubiquitous bacteria in livestock-associated environments where they may act as reservoirs of antimicrobial resistance (AMR) genes for pathogens such as Staphylococcus aureus. Here, we tested whether housing conditions in pig farms could influence the overall AMR-NAS burden. Two hundred and forty porcine commensal and environmental NAS isolates from three different farm types (conventional, alternative, and organic) were tested for phenotypic antimicrobial susceptibility and subjected to whole genome sequencing. Genomic data were analysed regarding species identity and AMR gene carriage. Seventeen different NAS species were identified across all farm types. In contrast to conventional farms, no AMR genes were detectable towards methicillin, aminoglycosides, and phenicols in organic farms. Additionally, AMR genes to macrolides and tetracycline were rare among NAS in organic farms, while such genes were common in conventional husbandries. No differences in AMR detection existed between farm types regarding fosfomycin, lincosamides, fusidic acid, and heavy metal resistance gene presence. The combined data show that husbandry conditions influence the occurrence of resistant and multidrug-resistant bacteria in livestock, suggesting that changing husbandry practices may be an appropriate means of limiting the spread of AMR bacteria on farms.}, language = {en} } @misc{TortMitrevaBrehmetal.2020, author = {Tort, Jose F. and Mitreva, Makedonka and Brehm, Klaus R. and Rinaldi, Gabriel}, title = {Editorial: Novel Frontiers in Helminth Genomics}, series = {Frontiers in Genetics}, volume = {11}, journal = {Frontiers in Genetics}, number = {791}, issn = {1664-8021}, doi = {10.3389/fgene.2020.00791}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-210209}, year = {2020}, abstract = {No abstract available.}, language = {en} } @phdthesis{Ebner2023, author = {Ebner, Sebastian Manfred}, title = {Antimykotikaresistenzen bei deutschen \(Candida\) \(auris\) Isolaten}, doi = {10.25972/OPUS-31806}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-318068}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2023}, abstract = {Bei dem 2009 erstbeschriebenen Hefepilz C. auris handelt es sich um einen Keim, welcher aufgrund von nosokomialen Ausbr{\"u}chen und hohen Antimykotikaresistenzen Aufmerksamkeit erregte. Ziel dieser Arbeit war es in Deutschland gesammelte Isolate bez{\"u}glich vorhandener Resistenzen und Mutationen in Resistenzregionen zu testen und das epidemiologische Geschehen hierzulande mit dem globalen Auftreten des Keims zu vergleichen. Bez{\"u}glich der durchgef{\"u}hrten Resistenztestungen wiesen die CLSI-konformen Testarten (YO-Platten und E-Test-Verfahren) meist vergleichbare Ergebnisse auf. F{\"u}r das EUCAST-konforme Mikrodilutionstestverfahren kann aufgrund eines stark ausgepr{\"a}gten paradoxen Wachstumseffekts nur Anidulafungin, nicht jedoch Caspofungin, zur Testung empfohlen werden. Insgesamt erwiesen sich 25 \% der Isolate als Caspofungin-resistent. Zwei Isolate zeigten eine Resistenz gegen{\"u}ber allen getesteten Echinocandinen (16,7 \%). Die h{\"o}chsten Resistenzraten wurden gegen{\"u}ber Fluconazol (92 \%) beobachtet. Zwei der Isolate zeigten sich gegen{\"u}ber Voriconazol resistent (16,7 \%). F{\"u}r Amphotericin B konnte eine Resistenzrate von 33,3 \% festgestellt werden. F{\"u}r die Wirkstoffe Posaconazol und Itraconazol erwiesen sich alle untersuchten Isolate als sensitiv. Dies konnte auch mit Ausnahme eines Isolates f{\"u}r 5-Flucytosin beobachtet werden. Die durch eine Sanger-Sequenzierung erhaltenen Sequenzen der Gene FKS1 und ERG11 wurden auf Mutationen untersucht, welche zu Aminos{\"a}uresubstitutionen im Gesamtprotein f{\"u}hrten. Hierbei ergaben sich f{\"u}r zwei Isolate (16,7 \%) Mutationen im FKS1-Hot Spot 1 (Typ S639F und S639Y). Beide Isolate zeigten sich in den AFST Echinocandin-resistent. Bei allen untersuchten Isolaten lagen Mutationen im ERG11 Gen vor. So fand sich in 8 F{\"a}llen eine Mutation des Typen Y132F (66,7 \%), in 3 F{\"a}llen der Typ K143R (25 \%) und in einem Fall der Typ F126L (8,3 \%). Im Rahmen eines anderen Projekts wurde mit den hier gewonnenen PCR-Produkten ein WGS durchgef{\"u}hrt, um die Isolate durch SNPs-Vergleich mit Referenzst{\"a}mmen phylogenetischen Clades zuzuordnen. Dabei konnten 91,7 \% der Isolate dem s{\"u}dasiatischen Clade I und ein Isolat dem s{\"u}dafrikanischen Clade III zugeordnet werden. Aufgrund der geringen epidemiologischen Fallzahlen in Deutschland scheint gegenw{\"a}rtig keine Bedrohung von C. auris auszugehen. Berichte aus anderen L{\"a}ndern konnten allerdings eine rasche, ausbruchartige Zunahme von C. auris F{\"a}llen nachweisen. So kann nur angeraten werden das infektiologische Geschehen in Deutschland weiterhin zu beobachten.}, subject = {Candida}, language = {de} } @article{KimShustaDoran2019, author = {Kim, Brandon J. and Shusta, Eric V. and Doran, Kelly S.}, title = {Past and current perspectives in modeling bacteria and blood-brain barrier interactions}, series = {Frontiers in Microbiology}, volume = {10}, journal = {Frontiers in Microbiology}, number = {1336}, doi = {10.3389/fmicb.2019.01336}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-201766}, year = {2019}, abstract = {The central nervous system (CNS) barriers are highly specialized cellular barriers that promote brain homeostasis while restricting pathogen and toxin entry. The primary cellular constituent regulating pathogen entry in most of these brain barriers is the brain endothelial cell (BEC) that exhibits properties that allow for tight regulation of CNS entry. Bacterial meningoencephalitis is a serious infection of the CNS and occurs when bacteria can cross specialized brain barriers and cause inflammation. Models have been developed to understand the bacterial - BEC interaction that lead to pathogen crossing into the CNS, however, these have been met with challenges due to these highly specialized BEC phenotypes. This perspective provides a brief overview and outlook of the in vivo and in vitro models currently being used to study bacterial brain penetration, and opinion on improved models for the future.}, language = {en} } @article{PageWallstabeLotheretal.2021, author = {Page, Lukas and Wallstabe, Julia and Lother, Jasmin and Bauser, Maximilian and Kniemeyer, Olaf and Strobel, Lea and Voltersen, Vera and Teutschbein, Janka and Hortschansky, Peter and Morton, Charles Oliver and Brakhage, Axel A. and Topp, Max and Einsele, Hermann and Wurster, Sebastian and Loeffler, Juergen}, title = {CcpA- and Shm2-Pulsed Myeloid Dendritic Cells Induce T-Cell Activation and Enhance the Neutrophilic Oxidative Burst Response to Aspergillus fumigatus}, series = {Frontiers in Immunology}, volume = {12}, journal = {Frontiers in Immunology}, issn = {1664-3224}, doi = {10.3389/fimmu.2021.659752}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-239493}, year = {2021}, abstract = {Aspergillus fumigatus causes life-threatening opportunistic infections in immunocompromised patients. As therapeutic outcomes of invasive aspergillosis (IA) are often unsatisfactory, the development of targeted immunotherapy remains an important goal. Linking the innate and adaptive immune system, dendritic cells are pivotal in anti-Aspergillus defense and have generated interest as a potential immunotherapeutic approach in IA. While monocyte-derived dendritic cells (moDCs) require ex vivo differentiation, antigen-pulsed primary myeloid dendritic cells (mDCs) may present a more immediate platform for immunotherapy. To that end, we compared the response patterns and cellular interactions of human primary mDCs and moDCs pulsed with an A. fumigatus lysate and two A. fumigatus proteins (CcpA and Shm2) in a serum-free, GMP-compliant medium. CcpA and Shm2 triggered significant upregulation of maturation markers in mDCs and, to a lesser extent, moDCs. Furthermore, both A. fumigatus proteins elicited the release of an array of key pro-inflammatory cytokines including TNF-α, IL-1β, IL-6, IL-8, and CCL3 from both DC populations. Compared to moDCs, CcpA- and Shm2-pulsed mDCs exhibited greater expression of MHC class II antigens and stimulated stronger proliferation and IFN-γ secretion from autologous CD4\(^+\) and CD8\(^+\) T-cells. Moreover, supernatants of CcpA- and Shm2-pulsed mDCs significantly enhanced the oxidative burst in allogeneic neutrophils co-cultured with A. fumigatus germ tubes. Taken together, our in vitro data suggest that ex vivo CcpA- and Shm2-pulsed primary mDCs have the potential to be developed into an immunotherapeutic approach to tackle IA.}, language = {en} } @article{ClausHubertBecheretal.2019, author = {Claus, Heike and Hubert, Kerstin and Becher, D{\"o}rte and Otto, Andreas and Pawlik, Marie-Christin and Lappann, Ines and Strobel, Lea and Vogel, Ulrich and Johswich, Kay}, title = {A homopolymeric adenosine tract in the promoter region of nspA influences factor H-mediated serum resistance in Neisseria meningitidis}, series = {Scientific Reports}, volume = {9}, journal = {Scientific Reports}, doi = {10.1038/s41598-019-39231-0}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-200956}, pages = {2736}, year = {2019}, abstract = {Although usually asymptomatically colonizing the human nasopharynx, the Gram-negative bacterium Neisseria meningitidis (meningococcus) can spread to the blood stream and cause invasive disease. For survival in blood, N. meningitidis evades the complement system by expression of a polysaccharide capsule and surface proteins sequestering the complement regulator factor H (fH). Meningococcal strains belonging to the sequence type (ST-) 41/44 clonal complex (cc41/44) cause a major proportion of serogroup B meningococcal disease worldwide, but they are also common in asymptomatic carriers. Proteome analysis comparing cc41/44 isolates from invasive disease versus carriage revealed differential expression levels of the outer membrane protein NspA, which binds fH. Deletion of nspA reduced serum resistance and NspA expression correlated with fH sequestration. Expression levels of NspA depended on the length of a homopolymeric tract in the nspA promoter: A 5-adenosine tract dictated low NspA expression, whereas a 6-adenosine motif guided high NspA expression. Screening German cc41/44 strain collections revealed the 6-adenosine motif in 39\% of disease isolates, but only in 3.4\% of carriage isolates. Thus, high NspA expression is associated with disease, but not strictly required. The 6-adenosine nspA promoter is most common to the cc41/44, but is also found in other hypervirulent clonal complexes.}, language = {en} } @article{KrausBrinkSiegel2019, author = {Kraus, Amelie J. and Brink, Benedikt G. and Siegel, T. Nicolai}, title = {Efficient and specific oligo-based depletion of rRNA}, series = {Scientific Reports}, volume = {9}, journal = {Scientific Reports}, doi = {10.1038/s41598-019-48692-2}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-224829}, year = {2019}, abstract = {In most organisms, ribosomal RNA (rRNA) contributes to >85\% of total RNA. Thus, to obtain useful information from RNA-sequencing (RNA-seq) analyses at reasonable sequencing depth, typically, mature polyadenylated transcripts are enriched or rRNA molecules are depleted. Targeted depletion of rRNA is particularly useful when studying transcripts lacking a poly(A) tail, such as some non-coding RNAs (ncRNAs), most bacterial RNAs and partially degraded or immature transcripts. While several commercially available kits allow effective rRNA depletion, their efficiency relies on a high degree of sequence homology between oligonucleotide probes and the target RNA. This restricts the use of such kits to a limited number of organisms with conserved rRNA sequences. In this study we describe the use of biotinylated oligos and streptavidin-coated paramagnetic beads for the efficient and specific depletion of trypanosomal rRNA. Our approach reduces the levels of the most abundant rRNA transcripts to less than 5\% with minimal off-target effects. By adjusting the sequence of the oligonucleotide probes, our approach can be used to deplete rRNAs or other abundant transcripts independent of species. Thus, our protocol provides a useful alternative for rRNA removal where enrichment of polyadenylated transcripts is not an option and commercial kits for rRNA are not available.}, language = {en} } @article{LieseSchoenvanderLindenetal.2019, author = {Liese, J. G. and Schoen, C. and van der Linden, M. and Lehmann, L. and Goettler, D. and Keller, S. and Maier, A. and Segerer, F. and Rose, M. A. and Streng, A.}, title = {Changes in the incidence and bacterial aetiology of paediatric parapneumonic pleural effusions/empyema in Germany, 2010-2017: a nationwide surveillance study}, series = {Clinical Microbiology and Infection}, volume = {25}, journal = {Clinical Microbiology and Infection}, doi = {10.1016/j.cmi.2018.10.020}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-236866}, pages = {857-864}, year = {2019}, abstract = {Objectives Parapneumonic pleural effusions/empyema (PPE/PE) are severe complications of community-acquired pneumonia. We investigated the bacterial aetiology and incidence of paediatric PPE/PE in Germany after the introduction of universal pneumococcal conjugate vaccine (PCV) immunization for infants. Methods Children <18 years of age hospitalized with pneumonia-associated PPE/PE necessitating pleural drainage or persisting >7 days were reported to the German Surveillance Unit for Rare Diseases in Childhood between October 2010 and June 2017. All bacteria detected in blood or pleural fluid (by culture/PCR) were included, with serotyping for Streptococcus pneumoniae. Results The median age of all 1447 PPE/PE patients was 5 years (interquartile range 3-10). In 488 of the 1447 children with PPE/PE (34\%), 541 bacteria (>40 species) were detected. Aerobic gram-positive cocci accounted for 469 of 541 bacteria detected (87\%); these were most frequently Streptococcus pneumoniae (41\%), Streptococcus pyogenes (19\%) and Staphylococcus aureus (6\%). Serotype 3 accounted for 45\% of 78 serotyped S. pneumoniae strains. Annual PPE/PE incidence varied between 14 (95\%CI 12-16) and 18 (95\%CI 16-21) PPE/PE per million children. Incidence of S. pneumoniae PPE/PE decreased from 3.5 (95\%CI 2.5-4.6) per million children in 2010/11 to 1.5 (95\%CI 0.9-2.4) in 2013/14 (p 0.002), followed by a re-increase to 2.2 (95\%CI 1.5-3.2) by 2016/17 (p 0.205). Conclusions In the era of widespread PCV immunization, cases of paediatric PPE/PE were still caused mainly by S. pneumoniae and, increasingly, by S. pyogenes. The re-increase in the incidence of PPE/PE overall and in S. pneumoniae-associated PPE/PE indicates ongoing changes in the bacterial aetiology and requires further surveillance.}, language = {en} } @phdthesis{Junghanns2024, author = {Junghanns, Lara Madeleine}, title = {Resistenzmechanismen gegen Amphotericin B in humanpathogenen Hefepilzen}, doi = {10.25972/OPUS-36986}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-369861}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {Die 2009 erstmals entdeckte Spezies C. auris erlangte binnen k{\"u}rzester Zeit zunehmend weltweite Aufmerksamkeit. Vor allem die Tendenz der Multiresistenzentwicklung und das rasche Ausl{\"o}sen von nosokomialen Infektionen erschweren den Umgang und die Therapie von C. auris Infektionen im Vergleich zu anderen Candida Spezien. Diese Dissertationsarbeit umfasst eine systematische Resistenzanalyse der im NRZMyk vorhandenen Stammsammlung aus C. auris und C. parapsilosis Isolaten, um Aufschluss {\"u}ber den Wirkmechanismus von Amphotericin B in Hefepilzen zu erlangen. Anhand der zun{\"a}chst durchgef{\"u}hrten Amphotericin B-Resistenztestungen kristallisierten sich CAU37 und CAU43 mit MHK-Werten bis zu 12 µg/ml als stark Amphotericin B-resistente Isolate heraus. Die Analyse der Sequenzierungsergebnisse zeigte bei beiden St{\"a}mmen eine Mutation im ERG4 Gen an Position 576, welche nicht eindeutig als alleinige Ursache f{\"u}r die verminderte Amphotericin B-Empfindlichkeit festgelegt werden konnte. Dennoch wurde im Rahmen eines Survival Assays bei beiden Amphotericin B-resistenten Isolaten anf{\"a}nglich eine konzentrationsabh{\"a}ngige Aktivit{\"a}t gegen{\"u}ber Amphotericin B festgestellt, bevor ein Nachwachsen der Kulturen beobachtet wurde. Somit wurde die Vermutung aufgestellt, dass lediglich ein Teil der aufgebrachten Candida-Zellen abget{\"o}tet wird und dies in einer Vermehrung der {\"u}berlebenden Zellen resultiert. Des Weiteren konnte im Rahmen von Resistenztestungen mit dem Sphingolipidinhibitor Myriocin nachgewiesen werden, dass vor allem in Amphotericin B-resistenten Isolaten eine deutliche Wirkungsverst{\"a}rkung des Polyens hervorgerufen wird. Diese Sensitivit{\"a}tssteigerung ist allgemein bei allen C. auris Isolaten zu beobachten, f{\"a}llt bei resistenten St{\"a}mmen jedoch deutlich st{\"a}rker aus. Hierdurch kam die Annahme auf, dass Amphotericin B-Resistenzen auch in m{\"o}glichen Ver{\"a}nderungen des Sphingolipid-Haushaltes begr{\"u}ndet sein k{\"o}nnten. Dar{\"u}ber hinaus scheint Myriocin keinen Einfluss auf Fluconazol-resistente oder FKS-mutierte Echinocandin-resistente C. auris St{\"a}mme zu haben. Das ebenfalls untersuchte und von Myriocin abgeleitete Medikament Fingolimod hatte jedoch ebenfalls keinen wirkungsverst{\"a}rkenden Effekt. Allerdings reagierte ein Großteil der C. auris Isolate (57,6 \%) sensitiv gegen{\"u}ber dem neusten medizinisch bekannten Triazol Isavuconazol und es konnte erstmalig ein ECV-Wert von 0,03125 µg/ml festgelegt werden. Ein valider Vergleich von C. auris zu C. parapsilosis war aufgrund der mangelnden Anzahl an C. parapsilosis Isolaten jedoch nicht m{\"o}glich}, subject = {Candida}, language = {de} } @phdthesis{PaetzelgebDitter2024, author = {P{\"a}tzel [geb. Ditter], Katharina Sabine}, title = {Molekulare Charakterisierung eines Mitgliedes der TNF-Rezeptor-Superfamilie des Fuchsbandwurmes \(Echinococcus\) \(multilocularis\)}, doi = {10.25972/OPUS-36939}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-369397}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {Die alveol{\"a}re Echinokokkose (AE), die durch den Fuchsbandwurm Echinococcus multilocularis verursacht wird, ist eine seltene jedoch schwere und oft t{\"o}dlich verlaufende Erkrankung. Aufgrund der sp{\"a}ten Diagnosestellung sind kurative Behandlungsmethoden h{\"a}ufig nicht durchf{\"u}hrbar und als einzige Behandlungsm{\"o}glichkeit bleibt eine lebenslange und nebenwirkungsreiche Therapie mit Benzimidazolen. Verbesserte Therapieoptionen durch die Entwicklung neuer Medikamente sind dringend notwendig. Hierf{\"u}r kann es hilfreich sein die Biologie des Fuchsbandwurmes und die Kommunikationswege zwischen Parasit und Wirt zu verstehen. Bereits in vorherigen Arbeiten als auch in dieser Arbeit erwiesen sich evolutionsgeschichtlich konservierte Signalwege als Kommunikationsweg zwischen dem Fuchsbandwurm und seinem Wirt von zentraler Rolle. Die Entschl{\"u}sselung des Echinococcus-Genoms gab Hinweise darauf, dass ein Mitglied der Tumornekrosefaktor-Rezeptor-Superfamilie, jedoch kein endogener TNF α {\"a}hnlicher Ligand im Genom kodiert wird. Ein Mitglied der TNFR-Superfamilie des Fuchsbandwurmes (EmTNFR) wurde in dieser Arbeit als membranst{\"a}ndiger Rezeptor mit einer intrazellul{\"a}ren Todesdom{\"a}ne (DD) und hoher {\"A}hnlichkeit zum humanen Typ 16 der TNF-Rezeptor-Superfamilie, auch 〖p75〗^NTR genannt, charakterisiert. Sowohl in bioinformatischen als auch in Sequenzanalysen wurden drei alternative Splicing-Formen von emtnfr (emtnfr, emtnfr-v2 und emtnfr-v3) nachgewiesen. emtnfr-v2 entsteht durch Alternatives Splicing und kodiert ein Protein, das keine intrazellul{\"a}re Todesdom{\"a}ne besitzt. emtnfr-v3 verwendet einen alternativen Transkriptionstart und wird von den letzten 3 Exons von emtnfr kodiert. emtnfr-v3, kodiert ein Protein ohne extrazellul{\"a}re Region, aber mit intrazellul{\"a}rer Todesdom{\"a}ne. Ein l{\"o}slicher TNF-Rezeptor konnte auf Proteinebene nicht nachgewiesen werden. Aufgrund von phylogenetischen Analysen und der Rezeptor-Struktur ist zu vermuten, dass EmTNFR ein p75NTR Homolog ist und damit der urspr{\"u}nglichen Form der TNF-Rezeptoren entspricht. Mitglieder eines intrazellul{\"a}ren TNF-Signalweges wurden in bioinformatischen Analysen beim Fuchsbandwurm E. multilocularis identifiziert. Expressionsuntersuchungen zeigten sowohl in Trankriptomdaten als auch auf Proteinebene eine starke Expression von EmTNFR in Prim{\"a}rzellen und im Metazestoden (MZ), dem pathogenen Stadium f{\"u}r den Zwischenwirt. Echinococcus-Stammzellkulturen zeigten nach RNA-Interferenz-basiertem Knockdown des EmTNFR-kodierenden Gens deutliche Entwicklungsdefekte. Des Weiteren zeigten Echinococcus-Stammzellkulturen nach einer Behandlung mit TNF-α, einem potentiellen Liganden des TNF-Rezeptors und einem zentralen Zytokin in der Immunabwehr des Zwischenwirtes, Entwicklungsfortschritte, wie eine verbesserte Bildung von MZ aus Stammzellen. Zus{\"a}tzlich wurde in whole-mount in situ Hybridisierungs-Versuchen eine ubiquit{\"a}re Expression von emtnfr in der Germinalschicht des MZ sowie eine Spezifit{\"a}t von emtnfr f{\"u}r den MZ, welcher urs{\"a}chlich f{\"u}r die AE ist, nachgewiesen. Somit scheinen sowohl EmTNFR als auch TNF-α eine wichtige Funktion bei der Entwicklung und Etablierung des Fuchsbandwurmes w{\"a}hrend der fr{\"u}hen Phase der Infektion des Zwischenwirtes zu haben. TNF-α k{\"o}nnte ein weiterer Faktor f{\"u}r den ausgepr{\"a}gten Organtropismus des Parasiten zur Leber sein, denn dort bestehen durch Kupfferzellen produzierte hohe lokale Konzentration von TNF-α. Zusammenfassend deuten die hier erarbeiteten Daten darauf hin, dass EmTNFR {\"u}ber die Bindung von Wirts-TNF-α bei der fr{\"u}hen Entwicklung des Echincoccus-Metazestoden eine Rolle spielt.}, subject = {Fuchsbandwurm}, language = {de} } @article{AlZabenMedyukhinaDietrichetal.2019, author = {Al-Zaben, Naim and Medyukhina, Anna and Dietrich, Stefanie and Marolda, Alessandra and H{\"u}nniger, Kerstin and Kurzai, Oliver and Figge, Marc Thilo}, title = {Automated tracking of label-free cells with enhanced recognition of whole tracks}, series = {Scientific Reports}, volume = {9}, journal = {Scientific Reports}, doi = {10.1038/s41598-019-39725-x}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-221093}, year = {2019}, abstract = {Migration and interactions of immune cells are routinely studied by time-lapse microscopy of in vitro migration and confrontation assays. To objectively quantify the dynamic behavior of cells, software tools for automated cell tracking can be applied. However, many existing tracking algorithms recognize only rather short fragments of a whole cell track and rely on cell staining to enhance cell segmentation. While our previously developed segmentation approach enables tracking of label-free cells, it still suffers from frequently recognizing only short track fragments. In this study, we identify sources of track fragmentation and provide solutions to obtain longer cell tracks. This is achieved by improving the detection of low-contrast cells and by optimizing the value of the gap size parameter, which defines the number of missing cell positions between track fragments that is accepted for still connecting them into one track. We find that the enhanced track recognition increases the average length of cell tracks up to 2.2-fold. Recognizing cell tracks as a whole will enable studying and quantifying more complex patterns of cell behavior, e.g. switches in migration mode or dependence of the phagocytosis efficiency on the number and type of preceding interactions. Such quantitative analyses will improve our understanding of how immune cells interact and function in health and disease.}, language = {en} } @article{KlotzHigginsSchaubmaretal.2019, author = {Klotz, Peter and Higgins, Paul G. and Schaubmar, Andreas R. and Failing, Klaus and Leidner, Ursula and Seifert, Harald and Scheufen, Sandra and Semmler, Torsten and Ewers, Christa}, title = {Seasonal Occurrence and Carbapenem Susceptibility of Bovine Acinetobacter baumannii in Germany}, series = {Frontiers in Microbiology}, volume = {10}, journal = {Frontiers in Microbiology}, doi = {10.3389/fmicb.2019.00272}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-325927}, year = {2019}, abstract = {Acinetobacter baumannii is one of the leading causes of nosocomial infections in humans. To investigate its prevalence, distribution of sequence types (STs), and antimicrobial resistance in cattle, we sampled 422 cattle, including 280 dairy cows, 59 beef cattle, and 83 calves over a 14-month period. Metadata, such as the previous use of antimicrobial agents and feeding, were collected to identify putative determining factors. Bacterial isolates were identified via MALDI-TOF/MS and PCR, antimicrobial susceptibility was evaluated via VITEK2 and antibiotic gradient tests, resistance genes were identified by PCR. Overall, 15.6\% of the cattle harbored A. baumannii, predominantly in the nose (60.3\% of the A. baumannii isolates). It was more frequent in dairy cows (21.1\%) than in beef cattle (6.8\%) and calves (2.4\%). A seasonal occurrence was shown with a peak between May and August. The rate of occurrence of A. baumannii was correlated with a history of use of 3rd generation cephalosporins in the last 6 months prior to sampling Multilocus sequence typing (Pasteur scheme) revealed 83 STs among 126 unique isolates. Nine of the bovine STs have previously been implicated in human infections. Besides known intrinsic resistance of the species, the isolates did not show additional resistance to the antimicrobial substances tested, including carbapenems. Our data suggest that cattle are not a reservoir for nosocomial A. baumannii but carry a highly diverse population of this species. Nevertheless, some STs seem to be able to colonize both cattle and humans.}, language = {en} } @article{WeissZieglerFliesseretal.2018, author = {Weiss, Esther and Ziegler, Sabrina and Fliesser, Mirjam and Schmitt, Anna-Lena and H{\"u}nniger, Kerstin and Kurzai, Oliver and Morton, Charles-Oliver and Einsele, Hermann and Loeffler, Juergen}, title = {First Insights in NK—DC Cross-Talk and the Importance of Soluble Factors During Infection With Aspergillus fumigatus}, series = {Frontiers in Cellular and Infection Microbiology}, volume = {8}, journal = {Frontiers in Cellular and Infection Microbiology}, doi = {10.3389/fcimb.2018.00288}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-233565}, year = {2018}, abstract = {Invasive aspergillosis (IA) is an infectious disease caused by the fungal pathogen Aspergillus fumigatus that mainly affects immunocompromised hosts. To investigate immune cell cross-talk during infection with A. fumigatus, we co-cultured natural killer (NK) cells and dendritic cells (DC) after stimulation with whole fungal structures, components of the fungal cell wall, fungal lysate or ligands for distinct fungal receptors. Both cell types showed activation after stimulation with fungal components and were able to transfer activation signals to the counterpart not stimulated cell type. Interestingly, DCs recognized a broader spectrum of fungal components and thereby initiated NK cell activation when those did not recognize fungal structures. These experiments highlighted the supportive function of DCs in NK cell activation. Furthermore, we focused on soluble DC mediated NK cell activation and showed that DCs stimulated with the TLR2/Dectin-1 ligand zymosan could maximally stimulate the expression of CD69 on NK cells. Thus, we investigated the influence of both receptors for zymosan, Dectin-1 and TLR2, which are highly expressed on DCs but show only minimal expression on NK cells. Specific focus was laid on the question whether Dectin-1 or TLR2 signaling in DCs is important for the secretion of soluble factors leading to NK cell activation. Our results show that Dectin-1 and TLR2 are negligible for NK cell activation. We conclude that besides Dectin-1 and TLR2 other receptors on DCs are able to compensate for the missing signal.}, language = {en} } @phdthesis{Polzin2024, author = {Polzin, Charlotte}, title = {Entwicklung eines Screeningverfahrens f{\"u}r Linezolid-resistente Enterokokken und Aufnahme der Pr{\"a}valenz}, doi = {10.25972/OPUS-37066}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-370665}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {Enterokokken geh{\"o}ren zu den bedeutendsten nosokomialen Keimen. Die Verbreitung von Multiresistenzen bei diesen Keimen stellt das deutsche Gesundheitssystem aufgrund von wenigen verbleibenden Therapieoptionen von Infektionen vor große Probleme. Die KRINKO des Robert-Koch-Instituts empfiehlt als m{\"o}gliche Pr{\"a}ventionsmaßnahme ein regelm{\"a}ßiges Screening auf Enterokokken mit Vancomycin- bzw. Linezolid-Resistenzen. Ziel dieser Arbeit war es, ein kulturelles Screeningverfahren f{\"u}r Linezolid-resistente Enterokokken (LRE) zu entwickeln und dieses anschließend im Routinescreening des Universit{\"a}tsklinikums W{\"u}rzburg zu etablieren. Es wurde ein Verfahren entwickelt, welches sich aus einem Anreicherungsschritt mit 3 mg/l Linezolid versetzter selektiver Enterococcosel-Bouillon und einer anschließenden Subkultivierung auf Linezolid-Enterococcosel-Agar mit 4 mg/l Linezolid zusammensetzt. In einer Simulation von klinischen Bedingungen zeigte sich eine gute Sensitivit{\"a}t und Spezifit{\"a}t. Das entwickelte Screeningverfahren wurde mit einem geringen Sensitivit{\"a}tsverlust und ohne zus{\"a}tzliche Belastung f{\"u}r die Patienten in das bestehende Routinescreening f{\"u}r Vancomycin-resistente Enterokokken des Universit{\"a}tsklinikums W{\"u}rzburg eingegliedert. Die nachgewiesen LRE zeigten unterschiedliche Resistenzmechanismen, wobei bei dem Großteil der Isolate Resistenzgene nachgewiesen werden konnten. Des Weiteren zeigte sich ein breit gestreuter genetischer Hintergrund. Viele der Isolate geh{\"o}rten genetischen Gruppen an, welche bisher kaum in hospitalisierten Patienten nachgewiesen wurden. Durch die labortechnische Weiterentwicklung von Screeningverfahren f{\"u}r LRE k{\"o}nnen diese m{\"o}glicherweise bald routinem{\"a}ßig in vielen Kliniken etabliert werden.}, subject = {Enterococcus}, language = {de} } @phdthesis{Fohmann2024, author = {Fohmann, Ingo}, title = {The Role of Sphingosine 1-phosphate and S1PR1-3 in the Pathophysiology of Meningococcal Meningitis}, doi = {10.25972/OPUS-36976}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-369764}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {Neisseria meningitidis (N. meningitidis) is an obligate human pathogen which causes live-threatening sepsis and meningitis. The fatality rate after meningococcal infection is high and surviving patients often suffer from severe sequelae. To cause meningitis, N. meningitidis must overcome the endothelium of the blood-brain barrier. The bacterium achieves this through the interaction with endothelial surface receptors leading to alternations of the cellular metabolism and signaling, which lastly results in cellular uptake and barrier traversal of N. meningitidis. Sphingosine 1-phosphate (S1P) is a lipid mediator that belongs to the class of sphingolipids and regulates the integrity of the blood-brain barrier through the interaction with its cognate receptors S1P receptors 1-3 (S1PR1-3). In this study, high performance liquid chromatography coupled with mass spectrometry (LC-MS/MS) was used to generate a time-resolved picture of the sphingolipid metabolism in a brain endothelial cell line (hCMEC/D3) upon meningococcal infection. Among various changes, S1P was elevated in the cellular compartment as well as in the supernatant of infected hCMEC/D3s. Analysis of mRNA expression in infected hCMEC/D3s with quantitative real-time polymerase chain reaction (RT-qPCR) revealed that the increase in S1P could be attributed to the enhanced expression of the S1P-generating enzyme sphingosine kinase 1 (SphK1). Antibody-based detection of SphK1 protein or phosphorylation at SphK1 residue Serine 225 in hCMEC/D3 plasma membrane fractions via Western Blot revealed that N. meningitidis also induced SphK1 phospho-activation and recruitment to the plasma membrane. Importantly, recruitment of SphK1 to the plasma membrane increases the probability of substrate encounter, thus elevating SphK activity. Enhanced SphK activity was also reflected on a functional level, as detected by a commercially available ATP depletion assay used for measuring the enzymatic activity of SphK. Infection of hCMEC/D3 cells with pilus-deficient mutants resulted in a lower SphK activation compared to the N. meningitidis wild type strain. hCMEC/D3 treatment with pilus-enriched protein fractions showed SphK activation similar to the infection with living bacteria and could be ascribed to pilus interaction with the membrane-proximal domain of cellular surface receptor CD147. Inhibition of SphK1 or SphK2 through pre-treatment with specific inhibitors or RNA interference reduced uptake of N. meningitidis into hCMEC/D3 cells, as measured with Gentamicin protection assays. Released S1P induced the phospho-activation of epidermal growth factor receptor (EGFR) via S1PR2 activation, whose expression was also increasing during infection. Furthermore, S1PR2 blockage had a preventive effect on bacterial invasion into hCMEC/D3 cells. On the contrary, activation of S1PR1+3 also reduced bacterial uptake, indicating an opposing regulatory role of S1PR1+3 and S1PR2 during N. meningitidis uptake. Moreover, SphK2 inhibition prevented inflammatory cytokine expression as well as release of interleukin-8 after N. meningitidis infection. Taken together, this study demonstrates the central role of S1P and its cognate receptors S1PR1-3 in the pathophysiology of meningococcal meningitis.}, subject = {Blut-Hirn-Schranke}, language = {en} }