Dokument-ID Dokumenttyp Verfasser/Autoren Herausgeber Haupttitel Abstract Auflage Verlagsort Verlag Erscheinungsjahr Seitenzahl Schriftenreihe Titel Schriftenreihe Bandzahl ISBN Quelle der Hochschulschrift Konferenzname Quelle:Titel Quelle:Jahrgang Quelle:Heftnummer Quelle:Erste Seite Quelle:Letzte Seite URN DOI Abteilungen OPUS4-13796 Wissenschaftlicher Artikel Biju, Joseph; Schwarz, Roland; Linke, Burkhard; Blom, Jochen; Becker, Anke; Claus, Heike; Goesmann, Alexander; Frosch, Matthias; Müller, Tobias; Vogel, Ulrich; Schoen, Christoph Virulence Evolution of the Human Pathogen Neisseria meningitidis by Recombination in the Core and Accessory Genome Background Neisseria meningitidis is a naturally transformable, facultative pathogen colonizing the human nasopharynx. Here, we analyze on a genome-wide level the impact of recombination on gene-complement diversity and virulence evolution in N. meningitidis. We combined comparative genome hybridization using microarrays (mCGH) and multilocus sequence typing (MLST) of 29 meningococcal isolates with computational comparison of a subset of seven meningococcal genome sequences. Principal Findings We found that lateral gene transfer of minimal mobile elements as well as prophages are major forces shaping meningococcal population structure. Extensive gene content comparison revealed novel associations of virulence with genetic elements besides the recently discovered meningococcal disease associated (MDA) island. In particular, we identified an association of virulence with a recently described canonical genomic island termed IHT-E and a differential distribution of genes encoding RTX toxin- and two-partner secretion systems among hyperinvasive and non-hyperinvasive lineages. By computationally screening also the core genome for signs of recombination, we provided evidence that about 40% of the meningococcal core genes are affected by recombination primarily within metabolic genes as well as genes involved in DNA replication and repair. By comparison with the results of previous mCGH studies, our data indicated that genetic structuring as revealed by mCGH is stable over time and highly similar for isolates from different geographic origins. Conclusions Recombination comprising lateral transfer of entire genes as well as homologous intragenic recombination has a profound impact on meningococcal population structure and genome composition. Our data support the hypothesis that meningococcal virulence is polygenic in nature and that differences in metabolism might contribute to virulence. 2011 e18441 PLoS One 6 4 urn:nbn:de:bvb:20-opus-137960 10.1371/journal.pone.0018441 Institut für Hygiene und Mikrobiologie OPUS4-13171 Wissenschaftlicher Artikel Marcus, U.; Vogel, U.; Schubert, A.; Claus, H.; Baetzing-Feigenbaum, J.; Hellenbrand, W.; Wichmann, O. A cluster of invasive meningococcal disease in young men who have sex with men in Berlin, October 2012 to May 2013 No abstract available. 2013 6-8 Eurosurveillance 18 28 urn:nbn:de:bvb:20-opus-131711 Institut für Hygiene und Mikrobiologie OPUS4-20049 Wissenschaftlicher Artikel Muenstermann, Marcel; Strobel, Lea; Klos, Andreas; Wetsel, Rick A.; Woodruff, Trent M.; Köhl, Jörg; Johswich, Kay O. Distinct roles of the anaphylatoxin receptors C3aR, C5aR1 and C5aR2 in experimental meningococcal infections 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. 2019 677-694 Virulence 10 1 urn:nbn:de:bvb:20-opus-200496 10.1080/21505594.2019.1640035 Institut für Hygiene und Mikrobiologie OPUS4-11303 Wissenschaftlicher Artikel Schubert-Unkmeir, Alexandra; Schneider-Schaulies, Sibylle; Gulbins, Erich; Hebling, Sabrina; Simonis, Alexander Differential Activation of Acid Sphingomyelinase and Ceramide Release Determines Invasiveness of Neisseria meningitidis into Brain Endothelial Cells The interaction with brain endothelial cells is central to the pathogenicity of Neisseria meningitidis infections. Here, we show that N. meningitidis causes transient activation of acid sphingomyelinase (ASM) followed by ceramide release in brain endothelial cells. In response to N. meningitidis infection, ASM and ceramide are displayed at the outer leaflet of the cell membrane and condense into large membrane platforms which also concentrate the ErbB2 receptor. The outer membrane protein Opc and phosphatidylcholine-specific phospholipase C that is activated upon binding of the pathogen to heparan sulfate proteoglycans, are required for N. meningitidis-mediated ASM activation. Pharmacologic or genetic ablation of ASM abrogated meningococcal internalization without affecting bacterial adherence. In accordance, the restricted invasiveness of a defined set of pathogenic isolates of the ST-11/ST-8 clonal complex into brain endothelial cells directly correlated with their restricted ability to induce ASM and ceramide release. In conclusion, ASM activation and ceramide release are essential for internalization of Opc-expressing meningococci into brain endothelial cells, and this segregates with invasiveness of N. meningitidis strains. Author Summary Neisseria meningitidis, an obligate human pathogen, is a causative agent of septicemia and meningitis worldwide. Meningococcal infection manifests in a variety of forms, including meningitis, meningococcemia with meningitis or meningococcemia without obvious meningitis. The interaction of N. meningitidis with human cells lining the blood vessels of the blood-cerebrospinal fluid barrier is a prerequisite for the development of meningitis. As a major pathogenicity factor, the meningococcal outer membrane protein Opc enhances bacterial entry into brain endothelial cells, however, mechanisms underlying trapping of receptors and signaling molecules following this interaction remained elusive. We now show that Opc-expressing meningococci activate acid sphingomyelinase (ASM) in brain endothelial cells, which hydrolyses sphingomyelin to cause ceramide release and formation of extended ceramide-enriched membrane platforms wherein ErbB2, an important receptor involved in bacterial uptake, clusters. Mechanistically, ASM activation relied on binding of N. meningitidis to its attachment receptor, HSPG, followed by activation of PC-PLC. Meningococcal isolates of the ST-11 clonal complex, which are reported to be more likely to cause severe sepsis, but rarely meningitis, barely invaded brain endothelial cells and revealed a highly restricted ability to induce ASM and ceramide release. Thus, our results unravel a differential activation of the ASM/ceramide system by the species N. meningitidis determining its invasiveness into brain endothelial cells. 2014 urn:nbn:de:bvb:20-opus-113031 10.1371/journal.ppat.1004160 Institut für Hygiene und Mikrobiologie OPUS4-13145 Wissenschaftlicher Artikel Schwerk, Christian; Papandreou, Thalia; Schuhmann, Daniel; Nickol, Laura; Borkowski, Julia; Steinmann, Ulrike; Quednau, Natascha; Stump, Carolin; Weiss, Christel; Berger, Jürgen; Wolburg, Hartwig; Claus, Heike; Vogel, Ulrich; Ishikawa, Hiroshi; Tenenbaum, Tobias; Schroten, Horst Polar Invasion and Translocation of Neisseria meningitidis and Streptococcus suis in a Novel Human Model of the Blood-Cerebrospinal Fluid Barrier Acute bacterial meningitis is a life-threatening disease in humans. Discussed as entry sites for pathogens into the brain are the blood-brain and the blood-cerebrospinal fluid barrier (BCSFB). Although human brain microvascular endothelial cells (HBMEC) constitute a well established human in vitro model for the blood-brain barrier, until now no reliable human system presenting the BCSFB has been developed. Here, we describe for the first time a functional human BCSFB model based on human choroid plexus papilloma cells (HIBCPP), which display typical hallmarks of a BCSFB as the expression of junctional proteins and formation of tight junctions, a high electrical resistance and minimal levels of macromolecular flux when grown on transwell filters. Importantly, when challenged with the zoonotic pathogen Streptococcus suis or the human pathogenic bacterium Neisseria meningitidis the HIBCPP show polar bacterial invasion only from the physiologically relevant basolateral side. Meningococcal invasion is attenuated by the presence of a capsule and translocated N. meningitidis form microcolonies on the apical side of HIBCPP opposite of sites of entry. As a functionally relevant human model of the BCSFB the HIBCPP offer a wide range of options for analysis of disease-related mechanisms at the choroid plexus epithelium, especially involving human pathogens. 2012 e30069 PLoS One 7 1 urn:nbn:de:bvb:20-opus-131459 10.1371/journal.pone.0030069 Institut für Hygiene und Mikrobiologie OPUS4-17987 Wissenschaftlicher Artikel Taha, Muhamed-Kheir; Claus, Heike; Lappann, Martin; Veyrier, Frédéric J.; Otto, Andreas; Becher, Dörte; Deghmane, Ala-Eddine; Frosch, Matthias; Hellenbrand, Wiebke; Hong, Eva; du Châtelet, Isabelle Parent; Prior, Karola; Harmsen, Dag; Vogel, Ulrich Evolutionary Events Associated with an Outbreak of Meningococcal Disease in Men Who Have Sex with Men Meningococci spread via respiratory droplets, whereas the closely related gonococci are transmitted sexually. Several outbreaks of invasive meningococcal disease have been reported in Europe and the United States among men who have sex with men (MSM). We recently identified an outbreak of serogroup C meningococcal disease among MSM in Germany and France. In this study, genomic and proteomic techniques were used to analyze the outbreak isolates. In addition, genetically identical urethritis isolates were recovered from France and Germany and included in the analysis. Genome sequencing revealed that the isolates from the outbreak among MSM and from urethritis cases belonged to a clade within clonal complex 11. Proteome analysis showed they expressed nitrite reductase, enabling anaerobic growth as previously described for gonococci. Invasive isolates from MSM, but not urethritis isolates, further expressed functional human factor H binding protein associated with enhanced survival in a newly developed transgenic mouse model expressing human factor H, a complement regulatory protein. In conclusion, our data suggest that urethritis and outbreak isolates followed a joint adaptation route including adaption to the urogenital tract. 2016 PLoS ONE 11 5 urn:nbn:de:bvb:20-opus-179870 10.1371/journal.pone.0154047 Institut für Hygiene und Mikrobiologie