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303. Rat-to-elephant-to-human transmission of cowpox virus

Author

Kurth, Andreas, Wibbelt, Gudrun, Gerber, Hans-Peter, Petschaelis, Angelika, Pauli, Georg, and Nitsche, Andreas

Abstract

To the Editor: Despite the eradication of smallpox in the past century, other orthopoxviruses, such as monkeypox virus, vaccinia virus in Brazil, and cowpox virus (CPXV) in Europe (1), still [...]

Published
2008

305. Comprehensive molecular, genomic and phenotypic analysis of a major clone of Enterococcus faecalis MLST ST40

Author

Zischka, Melanie, Kuenne, Carsten T., Blom, Jochen, Wobser, Dominique, Sakinc, Tuekan, Schmidt-Hohagen, Kerstin, Dabrowski, P. Wojtek, Nitsche, Andreas, Huebner, Johannes, Hain, Torsten, Chakraborty, Trinad, Linke, Burkhard, Goesmann, Alexander, Voget, Sonja, Daniel, Rolf, Schomburg, Dietmar, Hauck, Ruediger, Hafez, Hafez M., Tielen, Petra, Jahn, Dieter, Solheim, Margrete, Sadowy, Ewa, Larsen, Jesper, Jensen, Lars Bogø, Ruiz-Garbajosa, Patricia, Perez, Dianelys Quinones, Mikalsen, Theresa, Bender, Jennifer, Steglich, Matthias, Nuebel, Ulrich, Witte, Wolfgang, Werner, Guido, Zischka, Melanie, Kuenne, Carsten T., Blom, Jochen, Wobser, Dominique, Sakinc, Tuekan, Schmidt-Hohagen, Kerstin, Dabrowski, P. Wojtek, Nitsche, Andreas, Huebner, Johannes, Hain, Torsten, Chakraborty, Trinad, Linke, Burkhard, Goesmann, Alexander, Voget, Sonja, Daniel, Rolf, Schomburg, Dietmar, Hauck, Ruediger, Hafez, Hafez M., Tielen, Petra, Jahn, Dieter, Solheim, Margrete, Sadowy, Ewa, Larsen, Jesper, Jensen, Lars Bogø, Ruiz-Garbajosa, Patricia, Perez, Dianelys Quinones, Mikalsen, Theresa, Bender, Jennifer, Steglich, Matthias, Nuebel, Ulrich, Witte, Wolfgang, and Werner, Guido

Abstract

Background: Enterococcus faecalis is a multifaceted microorganism known to act as a beneficial intestinal commensal bacterium. It is also a dreaded nosocomial pathogen causing life-threatening infections in hospitalised patients. Isolates of a distinct MLST type ST40 represent the most frequent strain type of this species, distributed worldwide and originating from various sources (animal, human, environmental) and different conditions (colonisation/infection). Since enterococci are known to be highly recombinogenic we determined to analyse the microevolution and niche adaptation of this highly distributed clonal type. Results: We compared a set of 42 ST40 isolates by assessing key molecular determinants, performing whole genome sequencing (WGS) and a number of phenotypic assays including resistance profiling, formation of biofilm and utilisation of carbon sources. We generated the first circular closed reference genome of an E. faecalis isolate D32 of animal origin and compared it with the genomes of other reference strains. D32 was used as a template for detailed WGS comparisons of high-quality draft genomes of 14 ST40 isolates. Genomic and phylogenetic analyses suggest a high level of similarity regarding the core genome, also demonstrated by similar carbon utilisation patterns. Distribution of known and putative virulence-associated genes did not differentiate between ST40 strains from a commensal and clinical background or an animal or human source. Further analyses of mobile genetic elements (MGE) revealed genomic diversity owed to: (1) a modularly structured pathogenicity island; (2) a site-specifically integrated and previously unknown genomic island of 138 kb in two strains putatively involved in exopolysaccharide synthesis; and (3) isolate-specific plasmid and phage patterns. Moreover, we used different cell-biological and animal experiments to compare the isolate D32 with a closely related ST40 endocarditis isolate whose draft genome sequence was also gen

Published
2015

306. Genomic Analysis, Phenotype, and Virulence of the Historical Brazilian Smallpox Vaccine Strain IOC: Implications for the Origins and Evolutionary Relationships of Vaccinia Virus

Author

Medaglia, Maria Luiza G., primary, Moussatché, Nissin, additional, Nitsche, Andreas, additional, Dabrowski, Pjotr Wojtek, additional, Li, Yu, additional, Damon, Inger K., additional, Lucas, Carolina G. O., additional, Arruda, Luciana B., additional, and Damaso, Clarissa R., additional

Published
2015
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308. Comparison of 454 Ultra-Deep Sequencing and Allele-Specific Real-Time PCR with Regard to the Detection of Emerging Drug-Resistant Minor HIV-1 Variants after Antiretroviral Prophylaxis for Vertical Transmission

Author

Hauser, Andrea, primary, Kuecherer, Claudia, additional, Kunz, Andrea, additional, Dabrowski, Piotr Wojtek, additional, Radonić, Aleksandar, additional, Nitsche, Andreas, additional, Theuring, Stefanie, additional, Bannert, Norbert, additional, Sewangi, Julius, additional, Mbezi, Paulina, additional, Dugange, Festo, additional, Harms, Gundel, additional, and Meixenberger, Karolin, additional

Published
2015
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313. Rat cytomegalovirus (RCMV) English isolate and a newly identified Berlin isolate share similarities with but are separate as an anciently diverged clade from Mouse CMV and the Maastricht isolate of RCMV

Author

Geyer, Henriette, primary, Heaggans, Sarah, additional, Voigt, Sebastian, additional, Nitsche, Andreas, additional, Sandford, Gordon R., additional, Möller, Lars, additional, Brune, Wolfram, additional, Schmolz, Erik, additional, Ettinger, Jakob, additional, and Hayward, Gary S., additional

Published
2015
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314. Temporal and spatial analysis of the 2014–2015 Ebola virus outbreak in West Africa

Author

Carroll, Miles W., primary, Matthews, David A., additional, Hiscox, Julian A., additional, Elmore, Michael J., additional, Pollakis, Georgios, additional, Rambaut, Andrew, additional, Hewson, Roger, additional, García-Dorival, Isabel, additional, Bore, Joseph Akoi, additional, Koundouno, Raymond, additional, Abdellati, Saïd, additional, Afrough, Babak, additional, Aiyepada, John, additional, Akhilomen, Patience, additional, Asogun, Danny, additional, Atkinson, Barry, additional, Badusche, Marlis, additional, Bah, Amadou, additional, Bate, Simon, additional, Baumann, Jan, additional, Becker, Dirk, additional, Becker-Ziaja, Beate, additional, Bocquin, Anne, additional, Borremans, Benny, additional, Bosworth, Andrew, additional, Boettcher, Jan Peter, additional, Cannas, Angela, additional, Carletti, Fabrizio, additional, Castilletti, Concetta, additional, Clark, Simon, additional, Colavita, Francesca, additional, Diederich, Sandra, additional, Donatus, Adomeh, additional, Duraffour, Sophie, additional, Ehichioya, Deborah, additional, Ellerbrok, Heinz, additional, Fernandez-Garcia, Maria Dolores, additional, Fizet, Alexandra, additional, Fleischmann, Erna, additional, Gryseels, Sophie, additional, Hermelink, Antje, additional, Hinzmann, Julia, additional, Hopf-Guevara, Ute, additional, Ighodalo, Yemisi, additional, Jameson, Lisa, additional, Kelterbaum, Anne, additional, Kis, Zoltan, additional, Kloth, Stefan, additional, Kohl, Claudia, additional, Korva, Miša, additional, Kraus, Annette, additional, Kuisma, Eeva, additional, Kurth, Andreas, additional, Liedigk, Britta, additional, Logue, Christopher H., additional, Lüdtke, Anja, additional, Maes, Piet, additional, McCowen, James, additional, Mély, Stéphane, additional, Mertens, Marc, additional, Meschi, Silvia, additional, Meyer, Benjamin, additional, Michel, Janine, additional, Molkenthin, Peter, additional, Muñoz-Fontela, César, additional, Muth, Doreen, additional, Newman, Edmund N. C., additional, Ngabo, Didier, additional, Oestereich, Lisa, additional, Okosun, Jennifer, additional, Olokor, Thomas, additional, Omiunu, Racheal, additional, Omomoh, Emmanuel, additional, Pallasch, Elisa, additional, Pályi, Bernadett, additional, Portmann, Jasmine, additional, Pottage, Thomas, additional, Pratt, Catherine, additional, Priesnitz, Simone, additional, Quartu, Serena, additional, Rappe, Julie, additional, Repits, Johanna, additional, Richter, Martin, additional, Rudolf, Martin, additional, Sachse, Andreas, additional, Schmidt, Kristina Maria, additional, Schudt, Gordian, additional, Strecker, Thomas, additional, Thom, Ruth, additional, Thomas, Stephen, additional, Tobin, Ekaete, additional, Tolley, Howard, additional, Trautner, Jochen, additional, Vermoesen, Tine, additional, Vitoriano, Inês, additional, Wagner, Matthias, additional, Wolff, Svenja, additional, Yue, Constanze, additional, Capobianchi, Maria Rosaria, additional, Kretschmer, Birte, additional, Hall, Yper, additional, Kenny, John G., additional, Rickett, Natasha Y., additional, Dudas, Gytis, additional, Coltart, Cordelia E. M., additional, Kerber, Romy, additional, Steer, Damien, additional, Wright, Callum, additional, Senyah, Francis, additional, Keita, Sakoba, additional, Drury, Patrick, additional, Diallo, Boubacar, additional, de Clerck, Hilde, additional, Van Herp, Michel, additional, Sprecher, Armand, additional, Traore, Alexis, additional, Diakite, Mandiou, additional, Konde, Mandy Kader, additional, Koivogui, Lamine, additional, Magassouba, N’Faly, additional, Avšič-Županc, Tatjana, additional, Nitsche, Andreas, additional, Strasser, Marc, additional, Ippolito, Giuseppe, additional, Becker, Stephan, additional, Stoecker, Kilian, additional, Gabriel, Martin, additional, Raoul, Hervé, additional, Di Caro, Antonino, additional, Wölfel, Roman, additional, Formenty, Pierre, additional, and Günther, Stephan, additional

Published
2015
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315. Hantavirus-induced pathogenesis in mice with a humanized immune system

Author

Kobak, Lidija, primary, Raftery, Martin J., additional, Voigt, Sebastian, additional, Kühl, Anja A., additional, Kilic, Ergin, additional, Kurth, Andreas, additional, Witkowski, Peter, additional, Hofmann, Jörg, additional, Nitsche, Andreas, additional, Schaade, Lars, additional, Krüger, Detlev H., additional, and Schönrich, Günther, additional

Published
2015
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317. Comprehensive molecular, genomic and phenotypic analysis of a major clone of Enterococcus faecalis MLST ST40

Author

Zischka, Melanie, primary, Künne, Carsten T, additional, Blom, Jochen, additional, Wobser, Dominique, additional, Sakιnç, Türkân, additional, Schmidt-Hohagen, Kerstin, additional, Dabrowski, P Wojtek, additional, Nitsche, Andreas, additional, Hübner, Johannes, additional, Hain, Torsten, additional, Chakraborty, Trinad, additional, Linke, Burkhard, additional, Goesmann, Alexander, additional, Voget, Sonja, additional, Daniel, Rolf, additional, Schomburg, Dietmar, additional, Hauck, Rüdiger, additional, Hafez, Hafez M, additional, Tielen, Petra, additional, Jahn, Dieter, additional, Solheim, Margrete, additional, Sadowy, Ewa, additional, Larsen, Jesper, additional, Jensen, Lars B, additional, Ruiz-Garbajosa, Patricia, additional, Quiñones Pérez, Dianelys, additional, Mikalsen, Theresa, additional, Bender, Jennifer, additional, Steglich, Matthias, additional, Nübel, Ulrich, additional, Witte, Wolfgang, additional, and Werner, Guido, additional

Published
2015
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319. Isolation and Functional Characterization of the Novel Clostridium botulinum Neurotoxin A8 Subtype

Author

Kull, Skadi, primary, Schulz, K. Melanie, additional, Strotmeier, Jasmin Weisemann née, additional, Kirchner, Sebastian, additional, Schreiber, Tanja, additional, Bollenbach, Alexander, additional, Dabrowski, P. Wojtek, additional, Nitsche, Andreas, additional, Kalb, Suzanne R., additional, Dorner, Martin B., additional, Barr, John R., additional, Rummel, Andreas, additional, and Dorner, Brigitte G., additional

Published
2015
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320. 124. Isolation and functional characterization of the novel Clostridium botulinum A8 neurotoxin subtype

Author

Kull, Skadi, primary, Schulz, Melanie, additional, Weisemann, Jasmin, additional, Kirchner, Sebastian, additional, Schreiber, Tanja, additional, Bollenbach, Alexander, additional, Dabrowski, Wojtek, additional, Nitsche, Andreas, additional, Kalb, Suzanne, additional, Dorner, Martin, additional, Barr, John, additional, Rummel, Andreas, additional, and Dorner, Brigitte, additional

Published
2015
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324. Investigating the zoonotic origin of the West African Ebola epidemic

Author

Marí Saéz, Almudena, primary, Weiss, Sabrina, additional, Nowak, Kathrin, additional, Lapeyre, Vincent, additional, Zimmermann, Fee, additional, Düx, Ariane, additional, Kühl, Hjalmar S, additional, Kaba, Moussa, additional, Regnaut, Sebastien, additional, Merkel, Kevin, additional, Sachse, Andreas, additional, Thiesen, Ulla, additional, Villányi, Lili, additional, Boesch, Christophe, additional, Dabrowski, Piotr W, additional, Radonić, Aleksandar, additional, Nitsche, Andreas, additional, Leendertz, Siv Aina J, additional, Petterson, Stefan, additional, Becker, Stephan, additional, Krähling, Verena, additional, Couacy‐Hymann, Emmanuel, additional, Akoua‐Koffi, Chantal, additional, Weber, Natalie, additional, Schaade, Lars, additional, Fahr, Jakob, additional, Borchert, Matthias, additional, Gogarten, Jan F, additional, Calvignac‐Spencer, Sébastien, additional, and Leendertz, Fabian H, additional

Published
2014
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327. Modulation zellulärer Signalwege und antiviraler Mechanismen in Makrophagen durch Orthopockenviren

Author

Krüger, Detlev H., Nitsche, Andreas, Sutter, Gerd, Bourquain, Daniel, Krüger, Detlev H., Nitsche, Andreas, Sutter, Gerd, and Bourquain, Daniel

Abstract

Nach der Eradikation der humanen Pockenerkrankung stellen zoonotische Orthopockenvirus-(OPV-)Infektionen heute eine mögliche Bedrohung der öffentlichen Gesundheit dar. Hierbei sind insbesondere Kuhpocken-(CPXV), Affenpocken-(MPXV) und Vaccinia Viren (VACV) von Bedeutung. In dieser Arbeit wurde das Genexpressionsprofil humaner (HeLa) Zellen nach Infektion mit CPXV, MPXV oder VACV untersucht. Es wurden sowohl zelluläre Gene identifiziert, welche generell von allen verwendeten Viren reguliert wurden, als auch Gene, die eine Virus-spezifische Regulation durch individuelle OPV aufwiesen. Gemeinsamkeiten zeigten sich insbesondere zwischen CPXV und MPXV, welche, im Gegensatz zu VACV, die Expression zahlreicher Cytokine und Chemokine induzierten. Insbesondere für Interleukin-6, -8 und CXCL1 konnte auch auf Proteinebene eine gesteigerte Sekretion durch CPXV-infizierte Zellen nachgewiesen werden. Vermutlich aufgrund dieser Induktion, trat in vitro eine verstärkte Rekrutierung von Monozyten und Makrophagen in Folge einer CPXV-, nicht aber einer VACV-Infektion auf. Makrophagen spielen eine kontroverse Rolle im Rahmen einer OPV-Infektion und sind sowohl für deren Bekämpfung, als auch, im infizierten Zustand, für die Ausbreitung der Viren im Organismus von Bedeutung. Daher wurde die Replikationsfähigkeit von CPXV und VACV in Makrophagen charakterisiert. Der Virulenzfaktor p28, welcher von den meisten VACV Stämmen nicht kodiert wird, konnte als essentiell für die Replikation von CPXV in einer murinen Makrophagen-Zelllinie, primären peritonealen Makrophagen der Ratte und in Makrophagen aus primären humanen PBMCs identifiziert werden. In Anbetracht der Bedeutung der Replikationsfähigkeit in Makrophagen für die Ausbreitung einer OPV-Infektion im Wirtsorganismus, deuten diese Ergebnisse darauf hin, dass CPXV, im Fall einer weiteren Adaption an den Menschen, ein höheres Bedrohungspotential im Vergleich zu VACV aufweisen könnten., Today, following the eradication of human smallpox, zoonotic infections caused by orthopoxviruses (OPV) are emerging as a potential human health threat. Especially cowpox viruses (CPXV), vaccinia viruses (VACV), and monkeypox viruses (MPXV) are gaining importance as a cause of infectious disease of man and livestock. This study aimed to analyse and compare the gene expression profile of human (HeLa) cells following infection with CPXV, MPXV or VACV. Cellular genes were identified which were either commonly modulated by infection with any of the three viruses, or which were specifically modulated by one individual OPV. Particularly similar effects on cellular gene expression were observed in the case of CPXV and MPXV infection, which both induced the expression of several cytokine and chemokine genes. Especially interleukin-6, -8, and CXCL1 were strongly secreted by CPXV-infected cells but not by VACV-infected cells. Consequently, CPXV infection also induced a strong chemotactic recruitment of monocytes and macrophages in vitro in contrast to VACV infection. Especially macrophages are known to play a controversial role during OPV infection. On the one hand, macrophages are of importance for the control of the infection. On the other hand, infected macrophages also facilitate virus spread across the organism. Therefore, the capability of CPXV and VACV to replicate in macrophages was analysed. Thereby, the poxviral virulence factor p28, which is absent from most strains of VACV, was identified as an essential factor, allowing CPXV replication in a murine macrophage cell line, primary peritoneal rat macrophages and in human PBMC-derived macrophages. Concerning the importance of productively infected macrophages for OPV spread, these results suggest that CPXV, if further adapted to human beings as host species, may harbor a greater threat to human health when compared to VACV.

Published
2013

328. Einfluß des Humanen-Herpesvirus 6 (HHV-6) auf die Humane Chimären-Hämatopoese im Xeno-Transplantatmodell der NOD/SCID Maus

Author

Nitsche, Andreas

Subjects
NOD/SCID Mice, viruses, virus diseases, Herpesvirus, Hemopoiesis, 500 Naturwissenschaften und Mathematik::540 Chemie::540 Chemie und zugeordnete Wissenschaften
Abstract

Titel, Inhalt, Zusammenfassung, Summary Einleitung Material und Methoden Ergebnisse und Auswertung Diskussion, In der vorliegenden Arbeit wurde der Einfluß von HHV-6 auf die humane Hämatopoese in einem in vivo Modell untersucht. Zuerst wurden verschiedene sensitive und spezifische Nachweisverfahren für HHV-6 etabliert. Diese Nachweisverfahren beinhalteten den Nachweis von HHV-6 Proteinen mit monoklonalen Antikörpern, sowie HHV-6 DNA und HHV-6 RNA mit der PCR. Desweiteren wurde ein Echt-Zeit PCR Test zum quantitativen Nachweis von HHV-6 DNA etabliert. Die in dieser Arbeit entwickelten HHV-6 Nachweisverfahren wurden bereits in klinischen Studien evaluiert. Als Modell zur Untersuchung der humanen Hämatopoese wurde das Xenotransplantat-Modell der NOD/SCID Maus optimiert. Dazu mußte zuerst untersucht werden, ob HHV-6 pathogen für die NOD/SCID Maus ist. Nach Injektion von HHV-6 traten weder Veränderungen des Blutbildes, noch pathologische Veränderungen der Organe auf. Eine anhaltenden Infektion der Mäuse konnte weder auf der Basis des HHV-6 DNA Nachweises, noch des Antigen Nachweises beobachtet werden. Auch in vitro war eine Infektion muriner Zellen mit HHV-6 nicht möglich. HHV-6 repliziert dementsprechend nicht in Zellen der NOD/SCID Maus. Zur Untersuchung eines HHV-6 Einflusses auf die Chimären-Hämatopoese wurde das NOD/SCID Maus Modell bezüglich einer hohen Ausbeute humaner Zellen optimiert. Nach Transplantation von CB-MNC oder CB- CD34+ Zellen kam es zur Bildung einer humanen Multilinien-Hämatopoese in der NOD/SCID Maus. Die Supplementierung mit humanem IL-3 war bei Transplantation von CB-CD34+ Zellen mit zunehmendem Reinheitsgrad der Zellen essentieller und führte auch nach Transplantation von CB-MNC zu einer leicht erhöhten Bildung humaner Zellen und einer vermehrten Bildung myeloider Zellen gegenüber lymphoiden Vorläuferzellen. In einigen Versuchen konnten 80%-90% humane Zellen im Knochenmark der Mäuse detektiert werden. Mit Hilfe von LTBMC und Sekundär- Transplantationen konnte gezeigt werden, daß hIL-3 nicht nur zu einer erhöhten Proliferation der Zellen führt, sondern darüber hinaus das repopulierende Potential von PHSZ reduziert. PHSZ aus dem Knochenmark von Mäusen ohne hIL-3 Supplementierung hatten ein deutlich höheres repopulierendes Potential in sekundär-transplantierten Mäusen und LTBMC als hämatopoetische Stammzellen aus dem Knochenmark von Mäusen mit hIL-3 Supplementierung. Neben der Bildung humaner hämatopoetischer Zellen konnte nach Transplantation von hoch gereinigten CD34+ Zellen die Bildung humaner nicht-hämatopoetischer Zellen beobachtet werden. Offensichtlich enthält die Fraktion der CB-CD34+ Zellen auch Vorläuferzellen für Endothel- und Stromazellen. Die Produktion dieser Zellen wurde durch hIL-3 nicht beeinflußt. Die Infektion von CB-MNC mit HHV-6A resultierte in einer deutlich reduzierten Bildung humaner Zellen, unabhängig davon, ob die Zellen vor oder bereits nach der Transplantation infiziert wurden. Dabei war die Multilinien-Hämatopoese und die Bildung nicht- hämatopoetischer Zellen im Verhältnis zur Menge humaner Zellen nicht beeinträchtigt. HHV-6B hatte keinen Einfluß. Bei Infektion von CD34+ Zellen vor der Transplantation konnte keien reduzierte Bildung humaner Zellen beobachtet werden. Auch bei einer Infektion 3 Tage nach der Transplantation kam es zu keiner reduzierten Produktion humaner Zellen. Erst bei Infektion 12 Tage nach Transplantation zeigte sich der gleiche Effekt für HHV-6A, wie nach Transplantation von CB-MNC. HHV-6B hatte keinen Einfluß. Offensichtlich sind das "Homing" und die Bildung humaner Zellen aus CD34+ Zellen weder direkt noch indirekt durch HHV-6 beeinflußt. HHV-6A suszeptible Zellen müssen erst in der Maus gebildet werden. Bei Transplantation von CB-MNC werden diese bereits mit transplantiert. In einem in vitro Ansatz wurde der Einfluß von HHV-6 auf die Differenzierung von CD34+ Zellen zu Endothel- und Stromazellen gezeigt. Die HHV-6 Infektion führte zu einem schlechten Auswachsen der Kulturen und damit auch zu einer verminderten Bildung von Endothel- und Stromazellen. Ein spezifischer Effekt auf die Bildung dieser Zellen konnte nicht beobachtet werden. Mit zu diesem Zweck etablierten quantitativen RT-PCR Tests konnte HHV- 6B Infektion die reduzierte Transkription der KDR und vWF Gene gezeigt werden. HHV-6A hatte keinen Einfluß., Herpesvirus infections are common in childhood and lead to latency in the host. During immunosuppression, for example bone marrow transplantation, reactivation of human herpesvirus 6 (HHV-6) may cause bone marrow failure and may consequently cause the death of the patient. In the present thesis an in vivo model of human hematopoiesis, the NOD/SCID mouse, was applied to investigate the influence of HHV-6 on the repopulation and differentiation potential of hematopoietic pluripotent stem cells. First, sensitive detection assays for HHV-6A and HHV-6B were developed. These assays include the detection of HHV-6 specific proteins using monoclonal antibodies and the amplification of HHV-6 DNA and RNA by PCR. Moreover, a quantitative real-time PCR assay was developed to determine HHV-6 DNA load. These assays were finally evaluated in clinical studies. To ensure the validity of the mouse model, it had to be demonstrated, that HHV-6 is not pathogenic for NOD/SCID mice. After infection of cell free HHV-6 or HHV-6 infected cord blood mononuclear cells (CB-MNC), no pathological changes or variation in the blood cell count could be observed when compared to control mice. Neither a persistent nor a latent infection could be shown by antigen or DNA detection. Finally, the infection of murine cells in vitro was ineffective. These data suggest, that HHV-6 does not replicate in murine cells and is therefore not pathogenic for NOD/SCID mice. The NOD/SCID mouse model was optimized to obtain maximal engraftment of human cells. The transplantation of CB-MNC or CB-CD34+ cells resulted in multi-lineage hematopoiesis in the mouse bone marrow, blood and organs. The supplementation of human IL-3 lead to increased engraftment and production of myeloid cells compared to lymphoid cells. IL-3 supplementation was essential after CD34+-cell transplantation. Under optimal conditions engraftment rates of up to 90% of human cells in mouse bone marrow could be obtained. Using long-term bone marrow cultures and repeated transplantations, it could be demonstrated that, in addition to the proliferative effect of IL-3, the repopulating potential of stem cells was reduced. In the absence of IL-3, the stem cells remained in a quiescent state and proliferation could only be induced by stimuli like secondary transplantation or cell passage. In addition to the production of hematopoietic cells, non-hematopoietic (NHC) cells could be detected in the bone marrow of CD34+-cell transplanted mice. Obviously, precursor NHC cells with stromal characteristics were present in the CD34+-cell fraction. The formation of NHC was not affected by IL-3 supplementation. Infection of CB-MNC with HHV-6A resulted in a reduced engraftment. This effect was observed even when infection was performed 12 days post-transplantation. The formation of a multi-lineage hematopoiesis remained unchanged, no single cell type was suppressed by the infection. This reduced engraftment was shown to be coupled to virus replication, since inactivated virus had no effect. However, HHV-6B had no effect on the engraftment. In CD34+-cell transplantation experiments, no effect could be observed with HHV-6A and HHV-6B when infection was performed before or on the first days after transplantation. Only when infection was done at day 12 post- transplantation, was an effect observed as with CB-MNC transplantation.. To investigate whether the formation of NHC can be influenced by HHV-6 in vitro, culture conditions were developed to differentiate CD34+-cells into NHC. The presence of HHV-6B lead to a decreased growth of NHC in general. Using quantitative real-time RT-PCR assays for endothelial cell-related genes, a reduced expression of the VEGF-2 receptor gene (KDR) and the von Willebrandt factor gene could be shown. HHV-6A had no effect in this setting. The results presented here lead to the following hypothesis: The homing and engraftment of CD34+-cells is not influenced by HHV-6. HHV-6A susceptible cells have to be generated in the mouse by differentiation. Those HHV-6 susceptible cells are already present in the CB-MNC cell population. In these cells HHV-6 can survive and replicate affecting stem cell proliferation.

Published
2001
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330. NovelMycobacterium tuberculosisComplex Isolate from a Wild Chimpanzee

Author

Coscolla, Mireia, primary, Lewin, Astrid, additional, Metzger, Sonja, additional, Maetz-Rennsing, Kerstin, additional, Calvignac-Spencer, Sébastien, additional, Nitsche, Andreas, additional, Dabrowski, Pjotr Wojtek, additional, Radonic, Aleksandar, additional, Niemann, Stefan, additional, Parkhill, Julian, additional, Couacy-Hymann, Emmanuel, additional, Feldman, Julia, additional, Comas, Iñaki, additional, Boesch, Christophe, additional, Gagneux, Sebastien, additional, and Leendertz, Fabian H., additional

Published
2013
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333. A new quantitative real-time reverse transcriptase PCR assay and melting curve analysis for detection and genotyping of Ljungan virus strains

Author

Mantke, Oliver Donoso, Kallies, Rene, Niklasson, Bo, Nitsche, Andreas, Niedrig, Matthias, Mantke, Oliver Donoso, Kallies, Rene, Niklasson, Bo, Nitsche, Andreas, and Niedrig, Matthias

Abstract

Ljungan virus (LV), a new member of the Picornaviridoe, recently isolated from vole species in both Sweden and the USA, is suspected to be pathogenic for humans as an actiological agent in myocarditis, diabetes, neurological disease and perinatal disease. This study describes for the first time an RT-PCR assay that can identify and quantify LV infection in various tissue sample types using primers and two different minor-groove-binder probes targeting the 5'-untranslated region of the LV genome. The assay, evaluated using control samples derived from various virus cultures and rodent tissues, allows precise quantification of viral load over six orders of magnitude (101 to 106 viral copies per assay) for all known strains of LV with high sensitivity and specificity. Furthermore, a melting curve analysis (MCA) was developed using two amplicon-specific hybridisation probes that allows rapid genotyping of different LV strains. These new methods provide useful tools to investigate the putative role of LV as a pathogen in both rodents and humans.

Published
2007
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334. Pandemic Human Viruses Cause Decline of Endangered Great Apes

Author

Köndgen, Sophie, Kühl, Hjalmar, N'Goran, Paul K., Walsh, Peter D., Schenk, Svenja, Ernst, Nancy, Biek, Roman, Formenty, Pierre, Mätz-Rensing, Kerstin, Schweiger, Brunhilde, Junglen, Sandra, Ellerbrok, Heinz, Nitsche, Andreas, Briese, Thomas, Lipkin, W. Ian, Pauli, Georg, Boesch, Christophe, and Leendertz, Fabian H.

Published
2008
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337. Comparison of Shedding Characteristics of Seasonal Influenza Virus (Sub)Types and Influenza A(H1N1)pdm09; Germany, 2007–2011

Author

Suess, Thorsten, primary, Remschmidt, Cornelius, additional, Schink, Susanne B., additional, Schweiger, Brunhilde, additional, Heider, Alla, additional, Milde, Jeanette, additional, Nitsche, Andreas, additional, Schroeder, Kati, additional, Doellinger, Joerg, additional, Braun, Christian, additional, Haas, Walter, additional, Krause, Gérard, additional, and Buchholz, Udo, additional

Published
2012
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339. Complete Genome Sequence of the Porcine Isolate Enterococcus faecalis D32

Author

Zischka, Melanie, primary, Kuenne, Carsten, additional, Blom, Jochen, additional, Dabrowski, Piotr W., additional, Linke, Burkhard, additional, Hain, Torsten, additional, Nitsche, Andreas, additional, Goesmann, Alexander, additional, Larsen, Jesper, additional, Jensen, Lars B., additional, Witte, Wolfgang, additional, and Werner, Guido, additional

Published
2012
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349. Novel Adenoviruses in Wild Primates: a High Level of Genetic Diversity and Evidence of Zoonotic Transmissions

Author

Wevers, Diana, primary, Metzger, Sonja, additional, Babweteera, Fred, additional, Bieberbach, Marc, additional, Boesch, Christophe, additional, Cameron, Kenneth, additional, Couacy-Hymann, Emmanuel, additional, Cranfield, Mike, additional, Gray, Maryke, additional, Harris, Laurie A., additional, Head, Josephine, additional, Jeffery, Kathryn, additional, Knauf, Sascha, additional, Lankester, Felix, additional, Leendertz, Siv Aina J., additional, Lonsdorf, Elizabeth, additional, Mugisha, Lawrence, additional, Nitsche, Andreas, additional, Reed, Patricia, additional, Robbins, Martha, additional, Travis, Dominic A., additional, Zommers, Zinta, additional, Leendertz, Fabian H., additional, and Ehlers, Bernhard, additional

Published
2011
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