TY - THES A1 - Bergfeld, Arne T1 - Das pH-regulierte Protein 1 (Pra1) von \(Candida\) \(albicans\) moduliert CD4\(^+\) T-Zell-Antworten der Maus in vitro durch direkte Bindung an die T-Zell-Oberfläche T1 - The pH-regulated protein 1 (Pra1) of \(Candida\) \(albicans\) modulates mouse CD4\(^+\) T cell responses in vitro by directly binding to the T cell surface N2 - Infektionen durch C. albicans auf den Schleimhäuten sind eine häufige Erkrankung bei Patienten mit einer Schwächung der T-Zellimmunität. Blutstrominfektionen mit der Hefe C. albicans (Candidämie) stellen, vor allem bei Patienten auf Intensivstationen, eine nach wie vor bedrohliche Komplikation mit hoher Letalität dar. Das pH-regulierte Antigen 1 (Pra1) ist ein Protein, das von C. albicans produziert wird, auf der Oberfläche des Pilzes gebunden vorkommt und auch vom Pilz in den Überstand sezerniert wird. Im humanen System bindet das Protein an T-Zellen an das Oberflächenprotein CD46. Es ist des Weiteren bekannt, dass das Pra1 an bestimmte Immunzellen der Maus (Monozyten und Phagozyten) binden kann. Eine Bindung an T-Zellen der Maus ist bisher nicht beschrieben. Eine genaue Charakterisierung der Interaktion von Pra1 mit Immunzellen der Maus ist interessant, da die Maus als biologischer Modellorganismus zur Erforschung der Infektion mit C. albicans dient. In dieser Arbeit konnte gezeigt werden, dass rekombinantes Pra1 (rPra1) auch an Maus-CD4+ T-Zellen binden kann. Es wurden Einflussfaktoren auf die gefundene Bindung von Pra1 an CD4+ T- Zellen gesucht. Als ein Einflussfaktor wurde Zink identifiziert. Pra1 kann an freies Zink binden und durch Zugabe von ZnCl2 während der Inkubation von Pra1 mit T-Zellen kann das Signal von gebundenem Pra1 an CD4+ T-Zellen erhöht werden. Aspf2, ein Protein aus Aspergillus fumigatus mit großer Homologie zu Pra1, kann nicht an diese Zellen binden. Im in-vivo-Experiment mit Tieren, die mit C. albicans infiziert wurden, konnte kein wildtypisches sezerniertes Pra1 gebunden an T-Zellen nachgewiesen werden. Zellkulturüberstände von C. albicans zeigten nach Inkubation in vitro mit T-Zellen ein Signal für gebundenes Pra1 an CD4+ T-Zellen. Die Bindungskinetik von Pra1 an T-Zellen zeigte eine über die Zeit der Inkubation konstante Zunahme des Signals von zellgebundenem rPra1 an CD4+ T-Zellen. In der off-Kinetik fand sich eine Abnahme des Signals über die Zeit bis an die Grenze der Nachweisbarkeit. Der Bindungspartner von Pra1 auf T-Zellen konnte nicht identifiziert werden. Die strukturell und funktionell verwandten Oberflächenproteine Crry, CD59a und CD55 wurden auf Bindungsfähigkeit an T-Zellen in entsprechenden Knockout- Mäusen getestet, konnten jedoch als Rezeptor für Pra1 ausgeschlossen werden. Durch die Bindung von sezerniertem Pra1 an neutrophile Granulozyten wird die Fähigkeit dieser Zellen zur Phagozytose eingeschränkt. Die Bindung von Pra1 an CD4+ T-Zellen führt zur Kostimulation der T-Zellen, also zur verstärkten Zellaktivierung und Proliferation. Durch die Zugabe von 10 μM Zinkchlorid wird die kostimulatorische Aktivität von Pra1 verstärkt. Während der Zellaktivierung von Effektor-Memory-CD4+ T-Zellen reduziert rPra1 die Sekretion von IFN-γ. Diese Reduktion von IFN-γ-produzierenden Zellen entsteht nicht durch einen Einfluss von Pra1 während der Zellaktivierung von naiven CD4+ T-Zellen zu Th1-Zellen und auch nicht durch die Auslösung von Apoptose in IFN-γ-produzierenden Th1-Zellen. Die Bindung von Pra1 an CD4+- T-Zellen, die über den T-Zell-Rezeptor aktiviert werden, reduziert in vitro die Sekretion des Zytokins. Zusätzlich werden weitere Zytokine in ihrer sezernierten Menge reduziert wie IL-2 und TNF-α. N2 - Infections caused by C. albicans on mucosal surfaces are a common disease in patients suffering from suppression of the T cell immune defense. Blood stream infections by the yeast C. albicans (candedemia) represent still a severe complication in patients in intensive care units with high rates of lethality. The pH-regulated antigen 1 (Pra1) is a protein produced by C. albicans which is present on the surface of the fungi and is secreted into the supernatant of fungal cultures as well. Pra1 can bind to human T cells via the surface protein CD46. It is known, that this protein can also bind to certain immune cells of mice (monocytes and phagocytes). Binding to T cells of mice is not yet known. A characterization of the interaction of Pra1 with immune cells of mice would be valuable, because mice act as a biological model system for the investigation of infections with C. albicans. In this paper, it could be shown that recombinant Pra1 (rPra1) can bind to mouse CD4+ T cells as well. After the finding that rPra1 can bind to CD4+ T cells, different parameters determining this binding have been studied. Zinc was found to be one influencing factor on the binding. Pra1 can bind free zinc ions and by the addition of ZnCl2 while incubating T cells with Pra1 the signal of bound Pra1 to CD4+ T cells could be increased. Aspf2, a protein from Aspergillus fumigatus with high homology to Pra1, was not able to bind to these cells. In in-vivo-experiments with animals infected with C. albicans, no wild-typic secreted Pra1 was found bound to T cells. Supernatant from C. albicans cultures produced, after incubation in vitro, a signal for cell-bound Pra1 on CD4+ T cells. Kinetics of the binding of rPra1 to T cells showed a constant increase of signal over the time of incubation. The off-kinetics revealed a decrease of cell-bound rPra1 over time to the edge of detectability. The receptor of Pra1 on T cells has not been identified yet. The structurally and functionally comparable surface proteins Crry, CD59a and CD55 were tested in knockout mice for each of these proteins and could be excluded as possible receptors. After binding of secreted Pra1 to neutrophilic granulocytes these cells experience a decreased capacity to phagocytose pathogens. The binding of Pra1 to CD4+ T cells leads to a costimulation of T cells, which results in increased cell activation and proliferation. This costimulatory capacity of Pra1 can be augmented by adding 10 μM zinc chloride. During activation of naïve CD4+ T cells Pra1 reduces the secretion of IFN-γ. The reduction of IFN-γ-producing cells is not due to an influence of Pra1 during cell activation of naive CD4+ T cells to Th1 cells and is also not due to induction of apoptosis in IFN-γ-producing Th1 cells. The binding of Pra1 to ex-vivo isolated CD4+ T cells reduces the in vitro secretion of IFN-γ after stimulating these cells via their T cell receptor. Additionally, the secretion of IL-2 and TNF-α was reduced. KW - Candida albicans KW - T-Lymphozyt KW - Interferon KW - Tumor-Nekrose-Faktor KW - Interleukin 2 KW - C. albicans KW - CD4+ KW - T-Zelle KW - IFN-g KW - Pra1 Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-169716 ER - TY - JOUR A1 - Langenhorst, Daniela A1 - Haack, Stephanie A1 - Göb, Selina A1 - Uri, Anna A1 - Lühder, Fred A1 - Vanhove, Bernhard A1 - Hünig, Thomas A1 - Beyersdorf, Niklas T1 - CD28 costimulation of T helper 1 cells enhances cytokine release in vivo JF - Frontiers in Immunology N2 - Compared to naive T cells, differentiated T cells are thought to be less dependent on CD28 costimulation for full activation. To revisit the role of CD28 costimulation in mouse T cell recall responses, we adoptively transferred in vitro generated OT-II T helper (Th) 1 cells into C57BL/6 mice (Thy1.2\(^{+}\)) and then either blocked CD28–ligand interactions with Fab fragments of the anti-CD28 monoclonal antibody (mAb) E18 or deleted CD28 expression using inducible CD28 knock-out OT-II mice as T cell donors. After injection of ovalbumin protein in adjuvant into the recipient mice we observed that systemic interferon (IFN)γ release strongly depended on CD28 costimulation of the Th1 cells, while secondary clonal expansion was not reduced in the absence of CD28 costimulation. For human memory CD4\(^{+}\) T cell responses we also noted that cytokine release was reduced upon inhibition of CD28 costimulation. Together, our data highlight the so far underestimated role of CD28 costimulation for the reactivation of fully differentiated CD4\(^{+}\) T cells. KW - CD4\(^{+}\) T helper cells KW - T helper 1 cells KW - antigenic recall KW - CD28 costimulation KW - cytokine secretion KW - mouse KW - human Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-176726 VL - 9 IS - 1060 ER - TY - JOUR A1 - Saint Fleur-Lominy, Shella A1 - Maus, Mate A1 - Vaeth, Martin A1 - Lange, Ingo A1 - Zee, Isabelle A1 - Suh, David A1 - Liu, Cynthia A1 - Wu, Xiaojun A1 - Tikhonova, Anastasia A1 - Aifantis, Iannis A1 - Feske, Stefan T1 - STIM1 and STIM2 Mediate Cancer-Induced Inflammation in T Cell Acute Lymphoblastic Leukemia JF - Cell Reports N2 - T cell acute lymphoblastic leukemia (T-ALL) is commonly associated with activating mutations in the NOTCH1 pathway. Recent reports have shown a link between NOTCH1 signaling and intracellular Ca2+ homeostasis in T-ALL. Here, we investigate the role of store-operated Ca2+ entry (SOCE) mediated by the Ca2+ channel ORAI1 and its activators STIM1 and STIM2 in T-ALL. Deletion of STIM1 and STIM2 in leukemic cells abolishes SOCE and significantly prolongs the survival of mice in a NOTCH1-dependent model of T-ALL. The survival advantage is unrelated to the leukemic cell burden but is associated with the SOCE-dependent ability of malignant T lymphoblasts to cause inflammation in leukemia-infiltrated organs. Mice with STIM1/STIM2-deficient T-ALL show a markedly reduced necroinflammatory response in leukemia-infiltrated organs and downregulation of signaling pathways previously linked to cancer-induced inflammation. Our study shows that leukemic T lymphoblasts cause inflammation of leukemia-infiltrated organs that is dependent on SOCE. KW - T cell acute lymphoblastic leukemia KW - T-ALL KW - Notch1 KW - STIM1 KW - STIM2 KW - calcium KW - Ca2+ KW - CRAC KW - channel KW - inflammation KW - interferon KW - anemia KW - macrophages Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-227259 VL - 24 IS - 11 ER - TY - JOUR A1 - Rudovick, Ladius A1 - Brauner, Jan M. A1 - Englert, Johanna A1 - Seemann, Carolina A1 - Plugaru, Karina A1 - Kidenya, Benson R. A1 - Kalluvya, Samuel E. A1 - Scheller, Carsten A1 - Kasang, Christa T1 - Prevalence of pretreatment HIV drug resistance in Mwanza, Tanzania JF - Journal of Antimicrobial Chemotherapy N2 - Background: In a 2008-10 study, we found a pretreatment HIV drug resistance (PDR) prevalence of 18.2% in patients at Bugando Medical Centre (BMC) in Mwanza, Tanzania. Objectives: To determine the prevalence of PDR and transmitted HIV drug resistance (TDR) in patients visiting the BMC from 2013 to 2015. Methods: Adult outpatients were sequentially enrolled into two groups, separated by whether they were initiating ART. Previous exposure to antiretroviral drugs, except for prevention of mother-to-child transmission, was an exclusion criterion. HIV pol sequences were analysed according to WHO guidelines for surveillance of PDR and TDR. Results: Two hundred and thirty-five sequences were analysed (138 ART initiators, 97 non-initiators). The prevalence of PDR was 4.7% (95% CI 2.6%-8.2%) overall, 3.1% (95% CI 1.1%-8.7%) for non-initiators and 5.8% (95% CI 3.0%-11.0%) for ART initiators. PDR to NNRTIs and nucleoside or nucelotide reverse transcriptase inhibitors was found in 3.0% (95% CI 1.5%-6.0%) and 1.7% (95% CI 0.7%-4.3%) of patients, respectively. Resistance to PIs was not observed. The prevalence of TDR was 6.0% (95% CI 3.6%-9.8%). Conclusions: Prevalence of PDR significantly decreased compared with 2008-10 and was below the WHO-defined threshold for triggering a public health response. National and systematic surveillance is needed to inform Tanzania's public health strategy. KW - HIV KW - adult KW - anti-hiv agents KW - child KW - mothers KW - nucleosides KW - outpatients KW - reverse transcriptase inhibitors KW - tanzania KW - world health organization KW - guidelines KW - public health medicine KW - anti-retroviral agents KW - non-nucleoside reverse transcriptase inhibitors KW - surveillance KW - medical KW - exclusion criteria KW - prevention Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-227124 VL - 73 IS - 12 ER - TY - JOUR A1 - Riquelme, Paloma A1 - Haarer, Jan A1 - Kammler, Anja A1 - Walter, Lisa A1 - Tomiuk, Stefan A1 - Ahrens, Norbert A1 - Wege, Anja K. A1 - Goecze, Ivan A1 - Zecher, Daniel A1 - Banas, Bernhard A1 - Spang, Rainer A1 - Fändrich, Fred A1 - Lutz, Manfred B. A1 - Sawitzki, Birgit A1 - Schlitt, Hans J. A1 - Ochando, Jordi A1 - Geissler, Edward K. A1 - Hutchinson, James A. T1 - TIGIT\(^+\) iTregs elicited by human regulatory macrophages control T cell immunity JF - Nature Communications N2 - Human regulatory macrophages (Mreg) have shown early clinical promise as a cell-based adjunct immunosuppressive therapy in solid organ transplantation. It is hypothesised that recipient CD4(+) T cell responses are actively regulated through direct allorecognition of donor-derived Mregs. Here we show that human Mregs convert allogeneic CD4(+) T cells to IL-10-producing, TIGIT(+) FoxP3(+)-induced regulatory T cells that non-specifically suppress bystander T cells and inhibit dendritic cell maturation. Differentiation of Mreg-induced Tregs relies on multiple non-redundant mechanisms that are not exclusive to interaction of Mregs and T cells, including signals mediated by indoleamine 2,3-dioxygenase, TGF-beta, retinoic acid, Notch and progestagen-associated endometrial protein. Preoperative administration of donor-derived Mregs to living-donor kidney transplant recipients results in an acute increase in circulating TIGIT(+) Tregs. These results suggest a feed-forward mechanism by which Mreg treatment promotes allograft acceptance through rapid induction of direct-pathway Tregs. KW - Allotransplantation KW - Immunosuppression KW - Monocytes and macrophages KW - Regulatory T cells Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-226321 VL - 9 IS - 9 ER - TY - JOUR A1 - Vendelova, Emilia A1 - Ashour, Diyaaeldin A1 - Blank, Patrick A1 - Erhard, Florian A1 - Saliba, Antoine-Emmanuel A1 - Kalinke, Ulrich A1 - Lutz, Manfred B. T1 - Tolerogenic transcriptional signatures of steady-state and pathogen-induced dendritic cells JF - Frontiers in Immunology N2 - Dendritic cells (DCs) are key directors of tolerogenic and immunogenic immune responses. During the steady state, DCs maintain T cell tolerance to self-antigens by multiple mechanisms including inducing anergy, deletion, and Treg activity. All of these mechanisms help to prevent autoimmune diseases or other hyperreactivities. Different DC subsets contribute to pathogen recognition by expression of different subsets of pattern recognition receptors, including Toll-like receptors or C-type lectins. In addition to the triggering of immune responses in infected hosts, most pathogens have evolved mechanisms for evasion of targeted responses. One such strategy is characterized by adopting the host's T cell tolerance mechanisms. Understanding these tolerogenic mechanisms is of utmost importance for therapeutic approaches to treat immune pathologies, tumors and infections. Transcriptional profiling has developed into a potent tool for DC subset identification. Here, we review and compile pathogen-induced tolerogenic transcriptional signatures from mRNA profiling data of currently available bacterial- or helminth-induced transcriptional signatures. We compare them with signatures of tolerogenic steady-state DC subtypes to identify common and divergent strategies of pathogen induced immune evasion. Candidate molecules are discussed in detail. Our analysis provides further insights into tolerogenic DC signatures and their exploitation by different pathogens. KW - bacteria KW - helminths KW - immune evasion KW - mycobacteria KW - transcriptional profiling KW - tolerogenic dendritic cells KW - steady-state dendritic cells Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-175636 VL - 9 IS - 333 ER - TY - THES A1 - Fröhlich, Monika Gabriele T1 - Die Bedeutung von CD28 vermittelter Kostimulation für CD8 T-Zell-Gedächtnisreaktionen T1 - The role of CD28 costimulation for CD8 T-cell memory responses N2 - Immunologische Gedächtnisreaktionen sind die Grundlage um wiederkehrende Erreger schnell und effizient zu bekämpfen und um einen Impfschutz zu generieren. Das zellvermittelte Gedächtnis wird unter anderem durch CD8 Gedächtnis-T-Zellen aufgebaut, welche vor allem im Kontext von Immunreaktionen gegen intrazellulärer Erreger vonnöten sind, um bei Reinfektion mit den Erregerstämmen einen schnellen Schutz zu gewährleisten. Ein detailliertes Wissen über die Generierung, Kontrolle und Reaktivierung der Gedächtniszellen ist nützlich, um Gedächtnisreaktionen verstehen und lenken zu können. Durch die Entdeckung des TZR und CD28 wurden Meilensteine für das Verständnis der T-Zellaktivierung gelegt und die Grundlage geschaffen, CD8 Gedächtnisreaktionen zu verstehen. Auch wenn für primäre Immunreaktionen die „2-Signal-Theorie“ lange als erwiesen gilt, so blieb die Rolle der Kostimulation für Gedächtnisreaktionen lange umstritten. In dieser Arbeit wurden verschiedene methodische Herangehensweisen verwendet, mit denen durchgehend die Bedeutung von CD28 vermittelter Kostimulation für immunologische CD8 T-Zell-Gedächtnisreaktionen nachgewiesen wurde. CD28 blockierende Antikörper und CD28 induzierbar deletierbare Mauslinien wurden im Modellinfektionssystem mit Ovalbumin produzierenden Listeria monocytogenes zur Analyse der Primär- und Sekundärantworten verwendet. Mit diesen Methoden konnte eine Beeinträchtigung der Expansion von CD8 Gedächtniszellen in Abwesenheit von CD28 bewiesen werden. Weiterhin werden Effektorfunktionen wie Degranulation und Produktion von IFN-γ während der Sekundärinfektion in Abwesenheit von Kostimulation eingeschränkt. Mit Hilfe von Experimenten, bei denen CD28 suffizienten Mäusen eine geringe Anzahl an naiven, antigenspezifischen, CD28 deletierbaren CD8 T-Zellen transferiert wurden, wurde die Bedeutung der Kostimulation für die Expansion von Gedächtniszellen bestätigt, jedoch konnte überraschenderweise auch ein Anstieg der Effektorfunktionen in Abwesenheit von CD28 sowohl während der Primär- als auch der Sekundärantwort dokumentiert werden. Diese zur globalen Blockade bzw. Deletion widersprüchlichen Ergebnisse lassen eine Beteiligung anderer CD28 abhängiger Zelltypen an der Induktion der Effektorfunktionen der CD8 T-Zellen plausibel erscheinen, wie zum Beispiel Einflüsse von T-Helferzellen, welche die Effektorfunktionen positiv verstärken, solange sie selbst Kostimulationssignale empfangen können. Weiterhin konnte gezeigt werden, dass sich Gedächtniszellen an den CD28 defizienten Phänotyp – eine CD28 intakte immunologische Umgebung vorausgesetzt – adaptieren können, wenn ausreichend Zeit nach Deletion und vor Sekundärinfektion verstreichen konnte. N2 - Immunological memory is of vital importance for the fight against reoccurring pathogens and to protect organisms from infections. Important players are CD8 memory T-cells that are created mainly during intracellular infections to boost rapid cellular defenses upon reinfection. The understanding of the generation, control and reactivation of these memory cells is crucial to comprehend and regulate mechanisms of memory immune reactions. The discovery of the TCR and of the costimulator CD28 depict important milestones towards the understanding of activation of memory cells – and naive cells, of course. The paradigm of the two signal theory in the activation of naive T-cells has long been accepted but the role of CD28 mediated costimulation in secondary CD8 T-cell responses remains controversial. Several methodological approaches to investigate the impact of costimulation on memory CD8 T-cells were used in this work, all proving the importance of CD28 to mount robust memory responses. CD28 blocking antibodies and also inducibly CD28 deleting mice were used in both primary and secondary infections with Ovalbumin-producing Listeria monocytogenes to establish an impaired clonal expansion of CD8 memory T-cells in the absence of CD28 function. Furthermore, effector functions such as degranulation and IFN-γ production were reduced during the secondary immune response. Specific deletion of CD28 in CD8 cells in mice that were seeded with a naturally occuring number of antigen specific, CD28 deletable naive CD8 T-cells provided evidence for the importance of costimulatory signals for the clonal expansion but also revealed an increase of effector functions in the absence of CD28 both in the primary and in the secondary response. These findings suggest a participation of other CD28 responsive cells such as T-helper cells by supporting CD28 deleted effector cells to exert their effector functions under the terms of CD28 sufficiency in the other parts of the immune system. Furthermore, I found that the progeny of primed CD8 T-cells can adapt to the CD28 deficient phenotype if given sufficient time before reactivation. KW - Antigen CD28 KW - Antigen CD8 KW - CD8 Gedächtnisreaktionen KW - CD28 KW - Kostimulation KW - CD8 Effektorfunktionen Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-158791 ER - TY - JOUR A1 - Fichtner, Alina Suzann A1 - Karunakaran, Mohindar Murugesh A1 - Starick, Lisa A1 - Truman, Richard W. A1 - Herrmann, Thomas T1 - The armadillo (Dasypus novemcinctus): a witness but not a functional example for the emergence of the butyrophilin 3/Vγ9Vδ2 system in placental mammals JF - Frontiers in Immunology N2 - 1-5% of human blood T cells are Vγ9Vδ2 T cells whose T cell receptor (TCR) contain a TRGV9/TRGJP rearrangement and a TRDV2 comprising Vδ2-chain. They respond to phosphoantigens (PAgs) like isopentenyl pyrophosphate or (E)-4-hydroxy-3-methyl-but-2-enyl-pyrophosphate (HMBPP) in a butyrophilin 3 (BTN3)-dependent manner and may contribute to the control of mycobacterial infections. These cells were thought to be restricted to primates, but we demonstrated by analysis of genomic databases that TRGV9, TRDV2, and BTN3 genes coevolved and emerged together with placental mammals. Furthermore, we identified alpaca (Vicugna pacos) as species with typical Vγ9Vδ2 TCR rearrangements and currently aim to directly identify Vγ9Vδ2 T cells and BTN3. Other candidates to study this coevolution are the bottlenose dolphin (Tursiops truncatus) and the nine-banded armadillo (Dasypus novemcinctus) with genomic sequences encoding open reading frames for TRGV9, TRDV2, and the extracellular part of BTN3. Dolphins have been shown to express Vγ9- and Vδ2-like TCR chains and possess a predicted BTN3-like gene homologous to human BTN3A3. The other candidate, the armadillo, is of medical interest since it serves as a natural reservoir for Mycobacterium leprae. In this study, we analyzed the armadillo genome and found evidence for multiple non-functional BTN3 genes including genomic context which closely resembles the organization of the human, alpaca, and dolphin BTN3A3 loci. However, no BTN3 transcript could be detected in armadillo cDNA. Additionally, attempts to identify a functional TRGV9/TRGJP rearrangement via PCR failed. In contrast, complete TRDV2 gene segments preferentially rearranged with a TRDJ4 homolog were cloned and co-expressed with a human Vγ9-chain in murine hybridoma cells. These cells could be stimulated by immobilized anti-mouse CD3 antibody but not with human RAJI-RT1Bl cells and HMBPP. So far, the lack of expression of TRGV9 rearrangements and BTN3 renders the armadillo an unlikely candidate species for PAg-reactive Vγ9Vδ2 T cells. This is in line with the postulated coevolution of the three genes, where occurrence of Vγ9Vδ2 TCRs coincides with a functional BTN3 molecule. KW - TRDV2 KW - butyrophilin 3 KW - coevolution KW - nine-banded armadillo KW - placental mammals KW - Vγ9Vδ2 KW - TRGV9 Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-176044 VL - 9 IS - 265 ER - TY - JOUR A1 - Hennig, Thomas A1 - Michalski, Marco A1 - Rutkowski, Andrzej J. A1 - Djakovic, Lara A1 - Whisnant, Adam W. A1 - Friedl, Marie-Sophie A1 - Jha, Bhaskar Anand A1 - Baptista, Marisa A. P. A1 - L'Hernault, Anne A1 - Erhard, Florian A1 - Dölken, Lars A1 - Friedel, Caroline C. T1 - HSV-1-induced disruption of transcription termination resembles a cellular stress response but selectively increases chromatin accessibility downstream of genes JF - PLoS Pathogens N2 - Lytic herpes simplex virus 1 (HSV-1) infection triggers disruption of transcription termination (DoTT) of most cellular genes, resulting in extensive intergenic transcription. Similarly, cellular stress responses lead to gene-specific transcription downstream of genes (DoG). In this study, we performed a detailed comparison of DoTT/DoG transcription between HSV-1 infection, salt and heat stress in primary human fibroblasts using 4sU-seq and ATAC-seq. Although DoTT at late times of HSV-1 infection was substantially more prominent than DoG transcription in salt and heat stress, poly(A) read-through due to DoTT/DoG transcription and affected genes were significantly correlated between all three conditions, in particular at earlier times of infection. We speculate that HSV-1 either directly usurps a cellular stress response or disrupts the transcription termination machinery in other ways but with similar consequences. In contrast to previous reports, we found that inhibition of Ca\(^{2+}\) signaling by BAPTA-AM did not specifically inhibit DoG transcription but globally impaired transcription. Most importantly, HSV-1-induced DoTT, but not stress-induced DoG transcription, was accompanied by a strong increase in open chromatin downstream of the affected poly(A) sites. In its extent and kinetics, downstream open chromatin essentially matched the poly(A) read-through transcription. We show that this does not cause but rather requires DoTT as well as high levels of transcription into the genomic regions downstream of genes. This raises intriguing new questions regarding the role of histone repositioning in the wake of RNA Polymerase II passage downstream of impaired poly(A) site recognition. KW - DNA transcription KW - dogs KW - thermal stresses KW - chromatin KW - histones KW - gene expression KW - cellular stress responses KW - transcriptional termination Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-176350 VL - 14 IS - 3 ER - TY - JOUR A1 - Schierer, Stefan A1 - Ostalecki, Christian A1 - Zinser, Elisabeth A1 - Lamprecht, Ricarda A1 - Plosnita, Bianca A1 - Stich, Lena A1 - Doerrie, Jan A1 - Lutz, Manfred B A1 - Schuler, Gerold A1 - Baur, Andreas S T1 - Extracellular vesicles from mature dendritic cells (DC) differentiate monocytes into immature DC JF - Life Science Alliance N2 - 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. KW - medical research KW - immunology Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-228587 VL - 1 IS - 6 ER -