@phdthesis{Song2005, author = {Song, Bong-Seok}, title = {Morphodynamiken der Interaktion zwischen T-Zelle und dendritischer Zelle in dreidimensionaler extrazellul{\"a}rer Matrix}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-15397}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2005}, abstract = {Die Aktivierung der T Zelle bedarf der spezifischen Interaktion zwischen T Zelle und Antigen-pr{\"a}sentierender Zelle unter Ausbildung einer engen Anlagerung beider Zellmembranen („immunologische Synapse") f{\"u}r Rezeptoren-Interaktionen und konsekutive Signaltransduktion. In dreidimensionaler Kollagenmatrix zeigte sich ein stereotypes, dynamisches Muster bei der Interaktion zwischen CD45RO-positiven humanen T Zellen und antigenpr{\"a}sentierenden dendritischen Zellen. i) Die Kontaktaufnahme wurde stets {\"u}ber das Leading edge der T Zelle initiiert. ii) Beim dynamischen Kontakt wanderte die T Zelle polarisiert, mit vielen Richtungs{\"a}nderungen und mit reduzierter Geschwindigkeit auf der DC-Oberfl{\"a}che, nur unterbrochen von kurzen Stopp- und Abrundungsphasen. Der Uropod der T Zelle stand w{\"a}hrend der dynamischen Kontakts in kontinuierlicher Verbindung zur DC. iii) Die Losl{\"o}sung der T Zelle von der DC war ein aktiver Prozess, der durch Interaktion der Vorderfront der T Zelle zu benachbarten Kollagenfasern eingeleitet wurde, gefolgt von der L{\"o}sung des Zellk{\"o}rpers und des Uropods. Alternativ wurden Kontakte durch Uropod-mediierte Retention der T Zelle auf der DC-Oberfl{\"a}che verl{\"a}ngert. Zur dynamischen molekularen Charakterisierung der Kontaktfl{\"a}che wurde eine Methode zur Darstellung von Lipid-Rafts an lebenden Zellen in der 3D ECM mit BTRITC etabliert. Die Ergebnisse zeigen ein neues 3-Schritt-Konzept dynamischer und produktiver Interaktionen zwischen T Zelle und DC in vitro. Die assymetrische Kontaktzone impliziert distinkte Funktionen von Vorderfront und Uropod der T Zelle und definiert eine neuartige dynamische Kontaktform f{\"u}r die Signal{\"u}bertragung zwischen beweglichen Zellen.}, language = {de} } @article{BurekSalvadorFoerster2012, author = {Burek, Malgorzata and Salvador, Ellaine and F{\"o}rster, Carola Y.}, title = {Generation of an Immortalized Murine Brain Microvascular Endothelial Cell Line as an In Vitro Blood Brain Barrier Model}, series = {Journal of Visualized Experiments}, volume = {66}, journal = {Journal of Visualized Experiments}, number = {e4022}, doi = {10.3791/4022}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-126702}, year = {2012}, abstract = {Epithelial and endothelial cells (EC) are building paracellular barriers which protect the tissue from the external and internal environment. The blood-brain barrier (BBB) consisting of EC, astrocyte end-feet, pericytes and the basal membrane is responsible for the protection and homeostasis of the brain parenchyma. In vitro BBB models are common tools to study the structure and function of the BBB at the cellular level. A considerable number of different in vitro BBB models have been established for research in different laboratories to date. Usually, the cells are obtained from bovine, porcine, rat or mouse brain tissue (discussed in detail in the review by Wilhelm et al. 1). Human tissue samples are available only in a restricted number of laboratories or companies 2,3. While primary cell preparations are time consuming and the EC cultures can differ from batch to batch, the establishment of immortalized EC lines is the focus of scientific interest. Here, we present a method for establishing an immortalized brain microvascular EC line from neonatal mouse brain. We describe the procedure step-by-step listing the reagents and solutions used. The method established by our lab allows the isolation of a homogenous immortalized endothelial cell line within four to five weeks. The brain microvascular endothelial cell lines termed cEND 4 (from cerebral cortex) and cerebEND 5 (from cerebellar cortex), were isolated according to this procedure in the F{\"o}rster laboratory and have been effectively used for explanation of different physiological and pathological processes at the BBB. Using cEND and cerebEND we have demonstrated that these cells respond to glucocorticoid- 4,6-9 and estrogen-treatment 10 as well as to pro-infammatory mediators, such as TNFalpha 5,8. Moreover, we have studied the pathology of multiple sclerosis 11 and hypoxia 12,13 on the EC-level. The cEND and cerebEND lines can be considered as a good tool for studying the structure and function of the BBB, cellular responses of ECs to different stimuli or interaction of the EC with lymphocytes or cancer cells.}, language = {en} } @article{ReckeKonitzerLemckeetal.2018, author = {Recke, Andreas and Konitzer, Sarah and Lemcke, Susanne and Freitag, Miriam and Sommer, Nele Maxi and Abdelhady, Mohammad and Amoli, Mahsa M. and Benoit, Sandrine and El-Chennawy, Farha and Eldarouti, Mohammad and Eming, R{\"u}diger and Gl{\"a}ser, Regine and G{\"u}nther, Claudia and Hadaschik, Eva and Homey, Bernhard and Lieb, Wolfgang and Peitsch, Wiebke K. and Pf{\"o}hler, Claudia and Robati, Reza M. and Saeedi, Marjan and S{\´a}rdy, Mikl{\´o}s and Sticherling, Michael and Uzun, Soner and Worm, Margitta and Zillikens, Detlef and Ibrahim, Saleh and Vidarsson, Gestur and Schmidt, Enno}, title = {The p.Arg435His Variation of IgG3 With High Affinity to FcRn Is Associated With Susceptibility for Pemphigus Vulgaris-Analysis of Four Different Ethnic Cohorts}, series = {frontiers in Immunology}, volume = {9}, journal = {frontiers in Immunology}, doi = {10.3389/fimmu.2018.01788}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225073}, pages = {1788, 1-8}, year = {2018}, abstract = {IgG3 is the IgG subclass with the strongest effector functions among all four IgG subclasses and the highest degree of allelic variability among all constant immunoglobulin genes. Due to its genetic position, IgG3 is often the first isotype an antibody switches to before IgG1 or IgG4. Compared with the other IgG subclasses, it has a reduced half-life which is probably connected to a decreased affinity to the neonatal Fc receptor (FcRn). However, a few allelic variants harbor an amino acid replacement of His435 to Arg that reverts the half-life of the resulting IgG3 to the same level as the other IgG subclasses. Because of its functional impact, we hypothesized that the p.Arg435His variation could be associated with susceptibility to autoantibody-mediated diseases like pemphigus vulgaris (PV) and bullous pemphigoid (BP). Using a set of samples from German, Turkish, Egyptian, and Iranian patients and controls, we were able to demonstrate a genetic association of the p.Arg435His variation with PV risk, but not with BP risk. Our results suggest a hitherto unknown role for the function of IgG3 in the pathogenesis of PV.}, subject = {Diagnose}, language = {en} } @article{SchiererOstaleckiZinseretal.2018, author = {Schierer, Stefan and Ostalecki, Christian and Zinser, Elisabeth and Lamprecht, Ricarda and Plosnita, Bianca and Stich, Lena and Doerrie, Jan and Lutz, Manfred B and Schuler, Gerold and Baur, Andreas S}, title = {Extracellular vesicles from mature dendritic cells (DC) differentiate monocytes into immature DC}, series = {Life Science Alliance}, volume = {1}, journal = {Life Science Alliance}, number = {6}, doi = {10.26508/lsa.201800093}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-228587}, pages = {e201800093, 1-17}, year = {2018}, abstract = {During inflammation, murine and human monocytes can develop into dendritic cells (DC), but this process is not entirely understood. Here, we demonstrate that extracellular vesicles (EV) secreted by mature human DC (maDC) differentiate peripheral monocytes into immature DC, expressing a unique marker pattern, including 6-sulfo LacNAc (slan), Zbtb46, CD64, and CD14. While EV from both maDC and immature DC differentiated monocytes similar to GM-CSF/IL-4 stimulation, only maDC-EV produced precursors, which upon maturation stimulus developed into T-cell-activating and IL-12p70-secreting maDC. Mechanistically, maDC-EV induced cell signaling through GM-CSF, which was abundant in EV as were IL-4 and other cytokines and chemokines. When injected into the mouse skin, murine maDC-EV attracted immune cells including monocytes that developed activation markers typical for inflammatory cells. Skin-injected EV also reached lymph nodes, causing a similar immune cell infiltration. We conclude that DC-derived EV likely serve to perpetuate an immune reaction and may contribute to chronic inflammation.}, language = {en} } @phdthesis{Kaltdorf2020, author = {Kaltdorf, Martin Ernst}, title = {Analyse von regulatorischen Netzwerken bei Zelldifferenzierung und in der Infektionsbiologie}, doi = {10.25972/OPUS-19852}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-198526}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2020}, abstract = {Das zentrale Paradigma der Systembiologie zielt auf ein m{\"o}glichst umfassendes Ver-st{\"a}ndnis der komplexen Zusammenh{\"a}nge biologischer Systeme. Die in dieser Arbeit angewandten Methoden folgen diesem Grundsatz. Am Beispiel von drei auf Basis von Datenbanken und aktueller Literatur rekonstruier-ten Netzwerkmodellen konnte in der hier vorliegenden Arbeit die G{\"u}ltigkeit analyti-scher und pr{\"a}diktiver Algorithmen nachgewiesen werden, die in Form der Analy-sesoftware Jimena angewandt wurden. Die daraus resultierenden Ergebnisse sowohl f{\"u}r die Berechnung von stabilen Systemzust{\"a}nden, der dynamischen Simulation, als auch der Identifikation zentraler Kontrollknoten konnten experimentell validiert wer-den. Die Ergebnisse wurden in einem iterativen Prozess verwendet werden um das entsprechende Netzwerkmodell zu optimieren. Beim Vergleich des Verhaltens des semiquantitativ ausgewerteten regulatorischen Netzwerks zur Kontrolle der Differenzierung humaner mesenchymaler Stammzellen in Chondrozyten (Knorpelbildung), Osteoblasten (Knochenbildung) und Adipozyten (Fett-zellbildung) konnten 12 wichtige Faktoren (darunter: RUNX2, OSX/SP7, SOX9, TP53) mit Hilfe der Berechnung der Bedeutung (Kontrollzentralit{\"a}t der Netzwerkknoten identifi-ziert werden). Der Abgleich des simulierten Verhaltens dieses Netzwerkes ergab eine {\"U}bereinstimmung mit experimentellen Daten von 47,2\%, bei einem widerspr{\"u}chlichen Verhalten von ca. 25\%, dass unter anderem durch die tempor{\"a}re Natur experimentel-ler Messungen im Vergleich zu den terminalen Bedingungen des Berechnung der stabilen Systemzust{\"a}nde erkl{\"a}rt werden kann. Bei der Analyse des Netzwerkmodells der menschlichen Immunantwort auf eine Infek-tion durch A. fumigatus konnten vier Hauptregulatoren identifiziert werden (A. fumi-gatus, Blutpl{\"a}ttchen, hier Platelets genannt, und TNF), die im Zusammenspiel mit wei-teren Faktoren mit hohen Zentralit{\"a}tswerten (CCL5, IL1, IL6, Dectin-1, TLR2 und TLR4) f{\"a}hig sind das gesamte Netzwerkverhalten zu beeinflussen. Es konnte gezeigt werden, dass sich das Aktivit{\"a}tsverhalten von IL6 in Reaktion auf A. fumigatus und die regulato-rische Wirkung von Blutpl{\"a}ttchen mit den entsprechenden experimentellen Resultaten deckt. Die Simulation, sowie die Berechnung der stabilen Systemzust{\"a}nde der Immunantwort von A. thaliana auf eine Infektion durch Pseudomonas syringae konnte zeigen, dass die in silico Ergebnisse mit den experimentellen Ergebnissen {\"u}bereinstimmen. Zus{\"a}tzlich konnten mit Hilfe der Analyse der Zentralit{\"a}tswerte des Netzwerkmodells f{\"u}nf Master-regulatoren identifiziert werden: TGA Transkriptionsfaktor, Jasmons{\"a}ure, Ent-Kaurenoate-Oxidase, Ent-kaurene-Synthase und Aspartat-Semialdehyd-Dehydrogenase. W{\"a}hrend die ersteren beiden bereits lange als wichtige Regulatoren f{\"u}r die Gib-berellin-Synthese bekannt sind, ist die immunregulatorische Funktion von Aspartat-Semialdehyd-Dehydrogenase bisher weitgehend unbekannt.}, subject = {Netzwerksimulation}, language = {de} } @article{SchoenBerkingBiedermannetal.2020, author = {Sch{\"o}n, Michael P. and Berking, Carola and Biedermann, Tilo and Buhl, Timo and Erpenbeck, Luise and Eyerich, Kilian and Eyerich, Stefanie and Ghoreschi, Kamran and Goebeler, Matthias and Ludwig, Ralf J. and Sch{\"a}kel, Knut and Schilling, Bastian and Schlapbach, Christoph and Stary, Georg and von Stebut, Esther and Steinbrink, Kerstin}, title = {COVID-19 and immunological regulations - from basic and translational aspects to clinical implications}, series = {JDDG: Journal der Deutschen Dermatologischen Gesellschaft}, volume = {18}, journal = {JDDG: Journal der Deutschen Dermatologischen Gesellschaft}, number = {8}, doi = {10.1111/ddg.14169}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-218205}, pages = {795 -- 807}, year = {2020}, abstract = {The COVID-19 pandemic caused by SARS-CoV-2 has far-reaching direct and indirect medical consequences. These include both the course and treatment of diseases. It is becoming increasingly clear that infections with SARS-CoV-2 can cause considerable immunological alterations, which particularly also affect pathogenetically and/or therapeutically relevant factors. Against this background we summarize here the current state of knowledge on the interaction of SARS-CoV-2/COVID-19 with mediators of the acute phase of inflammation (TNF, IL-1, IL-6), type 1 and type 17 immune responses (IL-12, IL-23, IL-17, IL-36), type 2 immune reactions (IL-4, IL-13, IL-5, IL-31, IgE), B-cell immunity, checkpoint regulators (PD-1, PD-L1, CTLA4), and orally druggable signaling pathways (JAK, PDE4, calcineurin). In addition, we discuss in this context non-specific immune modulation by glucocorticosteroids, methotrexate, antimalarial drugs, azathioprine, dapsone, mycophenolate mofetil and fumaric acid esters, as well as neutrophil granulocyte-mediated innate immune mechanisms. From these recent findings we derive possible implications for the therapeutic modulation of said immunological mechanisms in connection with SARS-CoV-2/COVID-19. Although, of course, the greatest care should be taken with patients with immunologically mediated diseases or immunomodulating therapies, it appears that many treatments can also be carried out during the COVID-19 pandemic; some even appear to alleviate COVID-19.}, language = {en} } @article{SianHulsmannRiederer2021, author = {Sian-Hulsmann, Jeswinder and Riederer, Peter}, title = {The nigral coup in Parkinson's Disease by α-synuclein and its associated rebels}, series = {Cells}, volume = {10}, journal = {Cells}, number = {3}, issn = {2073-4409}, doi = {10.3390/cells10030598}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-234073}, year = {2021}, abstract = {The risk of Parkinson's disease increases with age. However, the etiology of the illness remains obscure. It appears highly likely that the neurodegenerative processes involve an array of elements that influence each other. In addition, genetic, endogenous, or exogenous toxins need to be considered as viable partners to the cellular degeneration. There is compelling evidence that indicate the key involvement of modified α-synuclein (Lewy bodies) at the very core of the pathogenesis of the disease. The accumulation of misfolded α-synuclein may be a consequence of some genetic defect or/and a failure of the protein clearance system. Importantly, α-synuclein pathology appears to be a common denominator for many cellular deleterious events such as oxidative stress, mitochondrial dysfunction, dopamine synaptic dysregulation, iron dyshomeostasis, and neuroinflammation. These factors probably employ a common apoptotic/or autophagic route in the final stages to execute cell death. The misfolded α-synuclein inclusions skillfully trigger or navigate these processes and thus amplify the dopamine neuron fatalities. Although the process of neuroinflammation may represent a secondary event, nevertheless, it executes a fundamental role in neurodegeneration. Some viral infections produce parkinsonism and exhibit similar characteristic neuropathological changes such as a modest brain dopamine deficit and α-synuclein pathology. Thus, viral infections may heighten the risk of developing PD. Alternatively, α-synuclein pathology may induce a dysfunctional immune system. Thus, sporadic Parkinson's disease is caused by multifactorial trigger factors and metabolic disturbances, which need to be considered for the development of potential drugs in the disorder.}, language = {en} } @article{StrengPrifertWeissbrichetal.2022, author = {Streng, Andrea and Prifert, Christiane and Weissbrich, Benedikt and Sauerbrei, Andreas and Krumbholz, Andi and Schmid-Ott, Ruprecht and Liese, Johannes G.}, title = {Similar severity of influenza primary and re-infections in pre-school children requiring outpatient treatment due to febrile acute respiratory illness: prospective, multicentre surveillance study (2013-2015)}, series = {BMC Infectious Diseases}, volume = {22}, journal = {BMC Infectious Diseases}, doi = {10.1186/s12879-021-06988-7}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-265841}, year = {2022}, abstract = {Background Influenza virus infections in immunologically na{\"i}ve children (primary infection) may be more severe than in children with re-infections who are already immunologically primed. We compared frequency and severity of influenza virus primary and re-infections in pre-school children requiring outpatient treatment. Methods Influenza-unvaccinated children 1-5 years of age presenting at pediatric practices with febrile acute respiratory infection < 48 h after symptom onset were enrolled in a prospective, cross-sectional, multicenter surveillance study (2013-2015). Influenza types/subtypes were PCR-confirmed from oropharyngeal swabs. Influenza type/subtype-specific IgG antibodies serving as surrogate markers for immunological priming were determined using ELISA/hemagglutination inhibition assays. The acute influenza disease was defined as primary infection/re-infection by the absence/presence of influenza type-specific immunoglobulin G (IgG) and, in a second approach, by the absence/presence of subtype-specific IgG. Socio-demographic and clinical data were also recorded. Results Of 217 influenza infections, 178 were due to influenza A (87 [49\%] primary infections, 91 [51\%] re-infections) and 39 were due to influenza B (38 [97\%] primary infections, one [3\%] re-infection). Children with "influenza A primary infections" showed fever with respiratory symptoms for a shorter period than children with "influenza A re-infections" (median 3 vs. 4 days; age-adjusted p = 0.03); other disease characteristics were similar. If primary infections and re-infections were defined based on influenza A subtypes, 122 (87\%) primary infections (78 "A(H3N2) primary infections", 44 "A(H1N1)pdm09 primary infections") and 18 (13\%) re-infections could be classified (14 "A(H3N2) re-infections" and 4 "A(H1N1)pdm09 re-infections"). Per subtype, primary infections and re-infections were of similar disease severity. Children with re-infections defined on the subtype level usually had non-protective IgG titers against the subtype of their acute infection (16 of 18; 89\%). Some patients infected by one of the influenza A subtypes showed protective IgG titers (≥ 1:40) against the other influenza A subtype (32/140; 23\%). Conclusions Pre-school children with acute influenza A primary infections and re-infections presented with similar frequency in pediatric practices. Contrary to expectation, severity of acute "influenza A primary infections" and "influenza A re-infections" were similar. Most "influenza A re-infections" defined on the type level turned out to be primary infections when defined based on the subtype. On the subtype level, re-infections were rare and of similar disease severity as primary infections of the same subtype. Subtype level re-infections were usually associated with low IgG levels for the specific subtype of the acute infection, suggesting only short-time humoral immunity induced by previous infection by this subtype. Overall, the results indicated recurring influenza virus infections in this age group and no or only limited heterosubtypic antibody-mediated cross-protection.}, language = {en} } @article{LodhaMuchsinJuergesetal.2023, author = {Lodha, Manivel and Muchsin, Ihsan and J{\"u}rges, Christopher and Juranic Lisnic, Vanda and L'Hernault, Anne and Rutkowski, Andrzej J. and Prusty, Bhupesh K. and Grothey, Arnhild and Milic, Andrea and Hennig, Thomas and Jonjic, Stipan and Friedel, Caroline C. and Erhard, Florian and D{\"o}lken, Lars}, title = {Decoding murine cytomegalovirus}, series = {PLOS Pathogens}, volume = {19}, journal = {PLOS Pathogens}, number = {5}, issn = {1553-7374}, doi = {10.1371/journal.ppat.1010992}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-350480}, year = {2023}, abstract = {The genomes of both human cytomegalovirus (HCMV) and murine cytomegalovirus (MCMV) were first sequenced over 20 years ago. Similar to HCMV, the MCMV genome had initially been proposed to harbor ≈170 open reading frames (ORFs). More recently, omics approaches revealed HCMV gene expression to be substantially more complex comprising several hundred viral ORFs. Here, we provide a state-of-the art reannotation of lytic MCMV gene expression based on integrative analysis of a large set of omics data. Our data reveal 365 viral transcription start sites (TiSS) that give rise to 380 and 454 viral transcripts and ORFs, respectively. The latter include 200 small ORFs, some of which represented the most highly expressed viral gene products. By combining TiSS profiling with metabolic RNA labelling and chemical nucleotide conversion sequencing (dSLAM-seq), we provide a detailed picture of the expression kinetics of viral transcription. This not only resulted in the identification of a novel MCMV immediate early transcript encoding the m166.5 ORF, which we termed ie4, but also revealed a group of well-expressed viral transcripts that are induced later than canonical true late genes and contain an initiator element (Inr) but no TATA- or TATT-box in their core promoters. We show that viral upstream ORFs (uORFs) tune gene expression of longer viral ORFs expressed in cis at translational level. Finally, we identify a truncated isoform of the viral NK-cell immune evasin m145 arising from a viral TiSS downstream of the canonical m145 mRNA. Despite being ≈5-fold more abundantly expressed than the canonical m145 protein it was not required for downregulating the NK cell ligand, MULT-I. In summary, our work will pave the way for future mechanistic studies on previously unknown cytomegalovirus gene products in an important virus animal model.}, 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} }