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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Verlauf der zellulären Immunantwort bei Lebendnierenempfängern - Messung von IFN-γ und IL-17 im Elispot-Assay

Grehn, Conrad 13 October 2015 (has links) (PDF)
Die Nierentransplantation ermöglicht Patienten die Wiederherstellung der Nierenfunktion. Aufgrund der begrenzten Verfügbarkeit an Organen nimmt dabei die Zahl der Transplantationen von einem lebenden Spender stetig zu. Zudem ermöglichen die präzisen und genauen Vorbereitungen und Abläufe bei Lebendnierenspenden eine bessere 5-Jahres-Überlebensrate als bei Kadaverspenden. Die genetische Verschiedenheit zwischen Spender und Empfänger bedingt jedoch eine lebenslange immunsuppressive Therapie, um Abstoßungsreaktionen und damit das Scheitern einer Organtransplantation zu verhindern. An den Universitätskliniken Leipzig und Halle/Saale besteht diese Therapie aus einer Dreifachkombination von Tacrolimus, Mycophenolat-Mofetil und Prednisolon, wobei mögliche Nebenwirkungen wie opportunistische Infektionen, kardiovaskuläre und metabolische Erkrankungen sowie Tumore in Kauf genommen werden. Zudem besteht für den immunsupprimmierten Organismus die ständige Gefahr einer Abstoßungsreaktion. Diese Aspekte führen bei den Empfängern zu einer massiven Einschränkung der Gesundheit und Lebensqualität. Inwieweit die ausgeprägte Immunsuppression notwendig ist, bleibt unklar und muss individuell festgelegt werden. Bisher existiert kein geeignetes Verfahren für ein Immunmonitoring, weshalb in vielen Fällen eine umfangreiche und überdosierte Immunsuppression in Kauf genommen wird. Im Rahmen dieser Arbeit wurde ein geeignetes Testverfahren, der Elispot-Assay, für die Expression der beiden proinflammatorischen Zytokine IFN-γ und IL-17 erstellt. Dafür wurden die PBMC der Spender und Empfänger aus Vollblut separiert, um sie anschließend sowohl separat als auch in einer Lymphozytenmischreaktion zu untersuchen. Die Darstellung von IL-17 konnte nur aufgrund einer zusätzlichen Stimulation mit OKT3 gelingen, während der IFN-γ-Elispot sowohl im Leerwert als auch unter Stimulation mit IL-2 zu ausreichenden Spotanzahlen führte. Die Spotanzahlen der Spender-PBMC wurden mit Hilfe von γ-Strahlung signifikant reduziert (IFN-γ: p=0,047 | IFN-γ + IL-2: p=0,007 | IL-17: p = 0,001), um in den Lymphozytenmischreaktionen die alleinige Zytokinausschüttung der Empfänger-PBMC messen zu können. Die Spender- PBMC fungierten dabei nur als Antigene. Insgesamt konnten zwischen 2009 und 2012 zwölf von siebzehn Patientenpaaren in die Studie eingeschlossen werden. Die Spotanzahlen der Paare wurden dabei sowohl im IFN-γ- als auch im IL-17-Elispot-Assay zu vier unterschiedlichen Zeitpunkten gemessen (vor Transplantation | 21±3 d postoperativ | 28±3 d postoperativ | 75±15 d postoperativ). In den meisten Fällen zeigte sich vor Transplantation eine erhöhte Spotanzahl im Vergleich zu den drei postoperativen Werten. Zudem stiegen die Spotanzahlen sowohl für IFN-γ als auch für IL-17 nach niedrigen Messergebnissen kurz nach der Transplantation im postoperativen Verlauf wieder an und erreichten in einigen Fällen die Spotanzahl der präoperativen Ausgangswerte. Ein signifikanter Unterschied konnte aufgrund der geringen Fallzahl nicht erreicht werden. Die kurzfristige Reduktion der Spotanzahlen postoperativ ist dabei aller Wahrscheinlichkeit nach auf die hohen Dosen an immunsuppressiven Medikamenten zurückzuführen. Insgesamt zeigten die Verläufe der IFN-γ- und der IL-17- Elispot-Assays ähnliche Verläufe. Daraus lässt sich schlussfolgern, dass der IL-17-Elispot- Assay in Bezug auf mögliche Abstoßungsreaktionen eine ähnliche Aussagekraft besitzen könnte wie der bereits vielfach untersuchte IFN-γ-Elispot-Assay. Weiterhin wurden die Messergebnisse mit der Serumkreatininmolarität verglichen. Diese zeigte präoperativ höhere Molaritäten als postoperativ, wobei die postoperativen Molaritäten im Verlauf, im Gegensatz zu den Elispot-Messungen, abnahmen, was das Einsetzen der Nierenfunktion widerspiegelt. Unter den zwölf Patientenpaaren gab es keine einzige nachgewiesene akute Abstoßungsreaktion, der Verlauf der Serumkreatininmolaritäten war bei allen zwölf Empfängern vergleichbar. Demzufolge konnten die Werte der Elispot-Assays nicht herangezogen werden, um an ihnen eine Abstoßungsreaktion der transplantierten Nieren erkennen zu können. Das präoperative Abschätzen einer möglichen Abstoßungsreaktion anhand der Elispot-Assays konnte aufgrund fehlender Abstoßungsreaktionen ebenfalls nicht untersucht werden. Zusätzlich wurde bei den Patienten eine HLA-Typisierung vorgenommen, wobei der Bereich von optimalen bis maximal ungünstigen Konstellationen reichten (HLA-Mismatch: 0-0-0 bis 2-2-2). Auch hier konnten die Ergebnisse nicht mit möglichen Abstoßungsreaktionen verglichen werden. In der vorliegenden Arbeit wurden zahlreiche Varianten untersucht, die das Abschätzen einer Immunreaktion nach Nierentransplantation (Immunmonitoring) ermöglichen könnten. Aufgrund fehlender Abstoßungsreaktionen bei den Empfängern konnte das Testverfahren nicht an den klinischen Verläufen validiert werden. Mit dem in dieser Arbeit entwickelten Messverfahren kann jedoch eine neue und größer angelegte Studie erfolgen, die in Zukunft ein Immunmonitoring bei Patienten nach Nierentransplantation ermöglicht. / Introduction Since the first kidney transplantation in the 1950ies, kidney transplantation is still being challenged by graft dysfunction and complete graft failure. Permanent immunsuppressive treatment is mandatory to avoid an unfavourable outcome. The treatment with Prednisolone, Tacrolimus and Mycophenolat-Mofetil may cause toxic side effects resulting in Diabetes mellitus, hypertension, infections and cancer. In the present study we tried to demonstrate that the amount of spots in the Enzyme linked immunospot assay (Elispot-Assay) of IFN-γ and IL-17 correlates with the probability of graft dysfuction and complete graft failure. We also compared the results to clinical parameters. Methods Between the years 2009 and 2012, twelve pairs of related living kidney transplantations were included in this study. From each pair blood samples were taken at four time points (before transplantation, and at 21±3, 28±3 and 75±15 days after kidney transplantation, respectively). After establishing the technique of IFN-γ- and IL-17-Elispot-Assays, we separated the periphale blood mononuclear cells (PBMC) and performed follow up examinations at the four time points mentioned above. The PBMC of each donor and each recipient were examined separatly, and in addition together in a lymphocyte mixed reaction. We stimulated the PBMC of the IFN-γ-Elispot with Interleukin-2 (IL-2) and the PBMC of the IL-17-Elispot with OKT3 to get significant characteristics. PBMC of the donors were irradiated with 30 Gy before mixing them with the PBMC of the recipients. We also took the HLA-matches and serum creatinine molarity to compare important clinical parameters with the results of the Elispot-Assays. Results Sufficient spots were measured using the unstimulated and stimulated IFN-γ-Elispot and the stimulated IL-17-Elispot. Radiation was significant at all three tests (IFN-γ: p=0,047 | IFN-γ + IL-2: p=0,007 | IL-17: p = 0,001). All twelve recipients showed a high number of spots before transplantation in both types of Elispot-Assays and most of them an increasing number of spots after a minimal turning point three weeks after transplantation. Due to the small number of cases, no significant results could be obtained at follow up. Non recipient developed a graft rejection as proven by biopsy or graft failure. The molarity of serum creatinine was permanently reduced whereas it was high before transplantation. Because of the abscence of any rejection episodes, HLA matches could not be compared. Discussion Due to the absence of rejection episodes or graft failure, no prediction for rejection by the IFN-γ- and IL-17-Elispot was possible. The low number of cases of living related kidney transplantation demonstrated the challange of the investigation of living related kidney transplantation. Although we could prove a significant effect of the irradiation of PBMC, there was no significant result in the follow up investigations. A higher number of cases are needed in future investigations. The established method of the IFN-γ- and IL-17-Elispot can be used in a future study with an extended number of cases and a longer follow up of time.
22

Verlauf der zellulären Immunantwort bei Lebendnierenempfängern - Messung von IFN-γ und IL-17 im Elispot-Assay

Grehn, Conrad 21 September 2015 (has links)
Die Nierentransplantation ermöglicht Patienten die Wiederherstellung der Nierenfunktion. Aufgrund der begrenzten Verfügbarkeit an Organen nimmt dabei die Zahl der Transplantationen von einem lebenden Spender stetig zu. Zudem ermöglichen die präzisen und genauen Vorbereitungen und Abläufe bei Lebendnierenspenden eine bessere 5-Jahres-Überlebensrate als bei Kadaverspenden. Die genetische Verschiedenheit zwischen Spender und Empfänger bedingt jedoch eine lebenslange immunsuppressive Therapie, um Abstoßungsreaktionen und damit das Scheitern einer Organtransplantation zu verhindern. An den Universitätskliniken Leipzig und Halle/Saale besteht diese Therapie aus einer Dreifachkombination von Tacrolimus, Mycophenolat-Mofetil und Prednisolon, wobei mögliche Nebenwirkungen wie opportunistische Infektionen, kardiovaskuläre und metabolische Erkrankungen sowie Tumore in Kauf genommen werden. Zudem besteht für den immunsupprimmierten Organismus die ständige Gefahr einer Abstoßungsreaktion. Diese Aspekte führen bei den Empfängern zu einer massiven Einschränkung der Gesundheit und Lebensqualität. Inwieweit die ausgeprägte Immunsuppression notwendig ist, bleibt unklar und muss individuell festgelegt werden. Bisher existiert kein geeignetes Verfahren für ein Immunmonitoring, weshalb in vielen Fällen eine umfangreiche und überdosierte Immunsuppression in Kauf genommen wird. Im Rahmen dieser Arbeit wurde ein geeignetes Testverfahren, der Elispot-Assay, für die Expression der beiden proinflammatorischen Zytokine IFN-γ und IL-17 erstellt. Dafür wurden die PBMC der Spender und Empfänger aus Vollblut separiert, um sie anschließend sowohl separat als auch in einer Lymphozytenmischreaktion zu untersuchen. Die Darstellung von IL-17 konnte nur aufgrund einer zusätzlichen Stimulation mit OKT3 gelingen, während der IFN-γ-Elispot sowohl im Leerwert als auch unter Stimulation mit IL-2 zu ausreichenden Spotanzahlen führte. Die Spotanzahlen der Spender-PBMC wurden mit Hilfe von γ-Strahlung signifikant reduziert (IFN-γ: p=0,047 | IFN-γ + IL-2: p=0,007 | IL-17: p = 0,001), um in den Lymphozytenmischreaktionen die alleinige Zytokinausschüttung der Empfänger-PBMC messen zu können. Die Spender- PBMC fungierten dabei nur als Antigene. Insgesamt konnten zwischen 2009 und 2012 zwölf von siebzehn Patientenpaaren in die Studie eingeschlossen werden. Die Spotanzahlen der Paare wurden dabei sowohl im IFN-γ- als auch im IL-17-Elispot-Assay zu vier unterschiedlichen Zeitpunkten gemessen (vor Transplantation | 21±3 d postoperativ | 28±3 d postoperativ | 75±15 d postoperativ). In den meisten Fällen zeigte sich vor Transplantation eine erhöhte Spotanzahl im Vergleich zu den drei postoperativen Werten. Zudem stiegen die Spotanzahlen sowohl für IFN-γ als auch für IL-17 nach niedrigen Messergebnissen kurz nach der Transplantation im postoperativen Verlauf wieder an und erreichten in einigen Fällen die Spotanzahl der präoperativen Ausgangswerte. Ein signifikanter Unterschied konnte aufgrund der geringen Fallzahl nicht erreicht werden. Die kurzfristige Reduktion der Spotanzahlen postoperativ ist dabei aller Wahrscheinlichkeit nach auf die hohen Dosen an immunsuppressiven Medikamenten zurückzuführen. Insgesamt zeigten die Verläufe der IFN-γ- und der IL-17- Elispot-Assays ähnliche Verläufe. Daraus lässt sich schlussfolgern, dass der IL-17-Elispot- Assay in Bezug auf mögliche Abstoßungsreaktionen eine ähnliche Aussagekraft besitzen könnte wie der bereits vielfach untersuchte IFN-γ-Elispot-Assay. Weiterhin wurden die Messergebnisse mit der Serumkreatininmolarität verglichen. Diese zeigte präoperativ höhere Molaritäten als postoperativ, wobei die postoperativen Molaritäten im Verlauf, im Gegensatz zu den Elispot-Messungen, abnahmen, was das Einsetzen der Nierenfunktion widerspiegelt. Unter den zwölf Patientenpaaren gab es keine einzige nachgewiesene akute Abstoßungsreaktion, der Verlauf der Serumkreatininmolaritäten war bei allen zwölf Empfängern vergleichbar. Demzufolge konnten die Werte der Elispot-Assays nicht herangezogen werden, um an ihnen eine Abstoßungsreaktion der transplantierten Nieren erkennen zu können. Das präoperative Abschätzen einer möglichen Abstoßungsreaktion anhand der Elispot-Assays konnte aufgrund fehlender Abstoßungsreaktionen ebenfalls nicht untersucht werden. Zusätzlich wurde bei den Patienten eine HLA-Typisierung vorgenommen, wobei der Bereich von optimalen bis maximal ungünstigen Konstellationen reichten (HLA-Mismatch: 0-0-0 bis 2-2-2). Auch hier konnten die Ergebnisse nicht mit möglichen Abstoßungsreaktionen verglichen werden. In der vorliegenden Arbeit wurden zahlreiche Varianten untersucht, die das Abschätzen einer Immunreaktion nach Nierentransplantation (Immunmonitoring) ermöglichen könnten. Aufgrund fehlender Abstoßungsreaktionen bei den Empfängern konnte das Testverfahren nicht an den klinischen Verläufen validiert werden. Mit dem in dieser Arbeit entwickelten Messverfahren kann jedoch eine neue und größer angelegte Studie erfolgen, die in Zukunft ein Immunmonitoring bei Patienten nach Nierentransplantation ermöglicht.:I Inhaltsverzeichnis................................................................I II Bibliographische Beschreibung....................................................................IV III Abkürzungsverzeichnis...................................................................................V 1 Einleitung...........................................................................................................01 1.1 Die T-Zell-vermittelte Immunität..................................................................01 1.1.1 Die verschiedenen Klassen der T-Lymphozyten................................ 01 1.1.2 Interferon-gamma als proinflammatorisches Zytokin......................... 04 1.1.3 Interleukin-17............................................................................................. 04 1.2 Die Nierentransplantation........................................................................... 05 1.2.1 Einführung.................................................................................................. 05 1.2.2 Besonderheiten der Lebendnierenspenden........................................ 06 1.3 Therapeutika bei Lebendnierenspenden................................................. 07 1.3.1 Calcineurininhibitoren............................................................................... 07 1.3.2 Prednisolon.................................................................................................. 08 1.3.3 Mycophenolat-Mofetil................................................................................. 09 1.4 Komplikationen bei Transplantationen....................................................... 10 1.4.1 Opportunistische Infektionen..................................................................... 10 1.4.2 Kardiovaskuläre und metabolische Erkrankungen................................ 11 1.4.3 Maligne Tumore.............................................................................................11 1.5 Transplantatrejektion........................................................................................ 12 1.5.1 Akute Abstoßungsreaktion............................................................................12 1.5.2 Chronische Transplantatnephropathie......................................................13 1.6 Zielsetzung der Arbeit.......................................................................................15 I2 Materialien und Methoden................................................................................. 16 2.1 Studiendesign.................................................................................................... 16 2.2 Materialien.......................................................................................................... 17 2.3 Methoden............................................................................................................ 19 2.3.1 Blutentnahmen................................................................................................ 19 2.3.2 Lymphozytenseparation.................................................................................19 2.3.3 Bestimmung der Zellzahl............................................................................... 20 2.3.4 Kryokonservierung der Zellen...................................................................... 20 2.3.5 Auftauen von kryokonservierten Zellen...................................................... 20 2.3.6 Bestrahlung von Zellen...................................................................................21 2.3.7 Stimulanzien.................................................................................................... 21 2.3.8 Durchflusszytometrie...................................................................................... 22 2.3.9 Elispot-Assay.................................................................................................... 23 3 Ergebnisse............................................................................................................... 29 3.1 Charakteristika der Patienten............................................................................ 29 3.2 Medikamentöse Therapieschemata nach Nierentransplantationen.......... 32 3.3 Versuche zur Etablierung des Elispot-Verfahrens......................................... 33 3.3.1 Vorversuche zum Nachweis von IFN-γ........................................................ 34 3.3.2 Vorversuche zum Nachweis von IL-17........................................................ 36 3.3.3 Versuche mit FKS-freiem Medium.................................................................37 3.3.4 Vitalitätsmessung in der Durchflusszytometrie.......................................... 38 3.4 Vergleich von Buffy Coats mit Patientenproben im Elispot-Assay..............38 3.5 Elispot-Assays der Spender-Empfänger-Paare............................................ 39 3.5.1 Ergebnisse der Elispot-Assays zum Nachweis von IFN-γ........................40 3.5.2 Ergebnisse der Elispot-Assays zum Nachweis von IL-17....................... 45 II3.6 Elispot-Ergebnisse unter Berücksichtigung der HLA-Kompatibilität........49 4 Diskussion............................................................................................................... 50 4.1 Bewertung der Methoden.................................................................................. 51 4.1.1 Patientenauswahl und -akquirierung........................................................... 51 4.1.2 Durchflusszytometrie....................................................................................... 51 4.1.3 Elispot-Assay..................................................................................................... 52 4.2 Vitalitätsmessung................................................................................................. 53 4.3 Elispot-Ergebnisse............................................................................................... 53 4.3.1 Vergleich der unbestrahlten und bestrahlten Elispot-Assays................... 53 4.3.2 Elispot-Assays der Patienten.......................................................................... 54 4.3.2.1 IFN-γ-Elispot-Assay........................................................................................ 54 4.3.2.2 IL-17-Elispot-Assay.........................................................................................56 4.3.2.3 IFN-γ-Elispot-Assay und IL-17-Elispot-Assay im Vergleich.................... 57 4.4 HLA-Merkmale und Serumkreatininmolarität...................................................58 4.5 Schlussfolgerung und Ausblick...........................................................................59 5 Zusammenfassung...................................................................................................62 6 Abstract...................................................................................................................... 65 7 Literaturverzeichnis................................................................................................. 67 8 Tabellenverzeichnis.................................................................................................83 9 Abbildungsverzeichnis........................................................................................... 84 10 Erklärung über die eigenständige Verfassung der Arbeit............................. 85 11 Lebenslauf..............................................................................................................86 12 Danksagung.......................................................................................................... 87 / Introduction Since the first kidney transplantation in the 1950ies, kidney transplantation is still being challenged by graft dysfunction and complete graft failure. Permanent immunsuppressive treatment is mandatory to avoid an unfavourable outcome. The treatment with Prednisolone, Tacrolimus and Mycophenolat-Mofetil may cause toxic side effects resulting in Diabetes mellitus, hypertension, infections and cancer. In the present study we tried to demonstrate that the amount of spots in the Enzyme linked immunospot assay (Elispot-Assay) of IFN-γ and IL-17 correlates with the probability of graft dysfuction and complete graft failure. We also compared the results to clinical parameters. Methods Between the years 2009 and 2012, twelve pairs of related living kidney transplantations were included in this study. From each pair blood samples were taken at four time points (before transplantation, and at 21±3, 28±3 and 75±15 days after kidney transplantation, respectively). After establishing the technique of IFN-γ- and IL-17-Elispot-Assays, we separated the periphale blood mononuclear cells (PBMC) and performed follow up examinations at the four time points mentioned above. The PBMC of each donor and each recipient were examined separatly, and in addition together in a lymphocyte mixed reaction. We stimulated the PBMC of the IFN-γ-Elispot with Interleukin-2 (IL-2) and the PBMC of the IL-17-Elispot with OKT3 to get significant characteristics. PBMC of the donors were irradiated with 30 Gy before mixing them with the PBMC of the recipients. We also took the HLA-matches and serum creatinine molarity to compare important clinical parameters with the results of the Elispot-Assays. Results Sufficient spots were measured using the unstimulated and stimulated IFN-γ-Elispot and the stimulated IL-17-Elispot. Radiation was significant at all three tests (IFN-γ: p=0,047 | IFN-γ + IL-2: p=0,007 | IL-17: p = 0,001). All twelve recipients showed a high number of spots before transplantation in both types of Elispot-Assays and most of them an increasing number of spots after a minimal turning point three weeks after transplantation. Due to the small number of cases, no significant results could be obtained at follow up. Non recipient developed a graft rejection as proven by biopsy or graft failure. The molarity of serum creatinine was permanently reduced whereas it was high before transplantation. Because of the abscence of any rejection episodes, HLA matches could not be compared. Discussion Due to the absence of rejection episodes or graft failure, no prediction for rejection by the IFN-γ- and IL-17-Elispot was possible. The low number of cases of living related kidney transplantation demonstrated the challange of the investigation of living related kidney transplantation. Although we could prove a significant effect of the irradiation of PBMC, there was no significant result in the follow up investigations. A higher number of cases are needed in future investigations. The established method of the IFN-γ- and IL-17-Elispot can be used in a future study with an extended number of cases and a longer follow up of time.:I Inhaltsverzeichnis................................................................I II Bibliographische Beschreibung....................................................................IV III Abkürzungsverzeichnis...................................................................................V 1 Einleitung...........................................................................................................01 1.1 Die T-Zell-vermittelte Immunität..................................................................01 1.1.1 Die verschiedenen Klassen der T-Lymphozyten................................ 01 1.1.2 Interferon-gamma als proinflammatorisches Zytokin......................... 04 1.1.3 Interleukin-17............................................................................................. 04 1.2 Die Nierentransplantation........................................................................... 05 1.2.1 Einführung.................................................................................................. 05 1.2.2 Besonderheiten der Lebendnierenspenden........................................ 06 1.3 Therapeutika bei Lebendnierenspenden................................................. 07 1.3.1 Calcineurininhibitoren............................................................................... 07 1.3.2 Prednisolon.................................................................................................. 08 1.3.3 Mycophenolat-Mofetil................................................................................. 09 1.4 Komplikationen bei Transplantationen....................................................... 10 1.4.1 Opportunistische Infektionen..................................................................... 10 1.4.2 Kardiovaskuläre und metabolische Erkrankungen................................ 11 1.4.3 Maligne Tumore.............................................................................................11 1.5 Transplantatrejektion........................................................................................ 12 1.5.1 Akute Abstoßungsreaktion............................................................................12 1.5.2 Chronische Transplantatnephropathie......................................................13 1.6 Zielsetzung der Arbeit.......................................................................................15 I2 Materialien und Methoden................................................................................. 16 2.1 Studiendesign.................................................................................................... 16 2.2 Materialien.......................................................................................................... 17 2.3 Methoden............................................................................................................ 19 2.3.1 Blutentnahmen................................................................................................ 19 2.3.2 Lymphozytenseparation.................................................................................19 2.3.3 Bestimmung der Zellzahl............................................................................... 20 2.3.4 Kryokonservierung der Zellen...................................................................... 20 2.3.5 Auftauen von kryokonservierten Zellen...................................................... 20 2.3.6 Bestrahlung von Zellen...................................................................................21 2.3.7 Stimulanzien.................................................................................................... 21 2.3.8 Durchflusszytometrie...................................................................................... 22 2.3.9 Elispot-Assay.................................................................................................... 23 3 Ergebnisse............................................................................................................... 29 3.1 Charakteristika der Patienten............................................................................ 29 3.2 Medikamentöse Therapieschemata nach Nierentransplantationen.......... 32 3.3 Versuche zur Etablierung des Elispot-Verfahrens......................................... 33 3.3.1 Vorversuche zum Nachweis von IFN-γ........................................................ 34 3.3.2 Vorversuche zum Nachweis von IL-17........................................................ 36 3.3.3 Versuche mit FKS-freiem Medium.................................................................37 3.3.4 Vitalitätsmessung in der Durchflusszytometrie.......................................... 38 3.4 Vergleich von Buffy Coats mit Patientenproben im Elispot-Assay..............38 3.5 Elispot-Assays der Spender-Empfänger-Paare............................................ 39 3.5.1 Ergebnisse der Elispot-Assays zum Nachweis von IFN-γ........................40 3.5.2 Ergebnisse der Elispot-Assays zum Nachweis von IL-17....................... 45 II3.6 Elispot-Ergebnisse unter Berücksichtigung der HLA-Kompatibilität........49 4 Diskussion............................................................................................................... 50 4.1 Bewertung der Methoden.................................................................................. 51 4.1.1 Patientenauswahl und -akquirierung........................................................... 51 4.1.2 Durchflusszytometrie....................................................................................... 51 4.1.3 Elispot-Assay..................................................................................................... 52 4.2 Vitalitätsmessung................................................................................................. 53 4.3 Elispot-Ergebnisse............................................................................................... 53 4.3.1 Vergleich der unbestrahlten und bestrahlten Elispot-Assays................... 53 4.3.2 Elispot-Assays der Patienten.......................................................................... 54 4.3.2.1 IFN-γ-Elispot-Assay........................................................................................ 54 4.3.2.2 IL-17-Elispot-Assay.........................................................................................56 4.3.2.3 IFN-γ-Elispot-Assay und IL-17-Elispot-Assay im Vergleich.................... 57 4.4 HLA-Merkmale und Serumkreatininmolarität...................................................58 4.5 Schlussfolgerung und Ausblick...........................................................................59 5 Zusammenfassung...................................................................................................62 6 Abstract...................................................................................................................... 65 7 Literaturverzeichnis................................................................................................. 67 8 Tabellenverzeichnis.................................................................................................83 9 Abbildungsverzeichnis........................................................................................... 84 10 Erklärung über die eigenständige Verfassung der Arbeit............................. 85 11 Lebenslauf..............................................................................................................86 12 Danksagung.......................................................................................................... 87
23

Etude des mécanismes immunitaires dans un modèle d'inflammation pulmonaire allergique chez la souris : rôles de l'interleukine-22 / Roles of interleukin-22 in a mouse model of allergic airways inflammation

Besnard, Anne-Gaëlle 17 December 2010 (has links)
L’asthme est une maladie inflammatoire chronique des voies aériennes. Chez les individus sensibles, l’inhalation d’allergènes entraine une inflammation pulmonaire se traduisant par des épisodes récurrents de toux, de difficultés respiratoires et une sécrétion de mucus. Des études réalisées chez l’animal ont mis en évidence un rôle crucial des lymphocytes Th2 et des cytokines associées (IL-4, IL-5 et IL-13). Plus récemment, il a été montré que les lymphocytes Th17 participaient à la physiopathologie de l’asthme. La présente étude s’intéresse à une cytokine majoritairement produite par les Th17 : l’IL-22. Différents travaux indiquent que cette cytokine serait impliquée dans l’immunitémucosale où elle exercerait des effets protecteurs ou pro-inflammatoires en fonction du modèle expérimental étudié. En utilisant un modèle murin d’inflammation pulmonaire allergique induite par l’ovalbumine, nous avons montré que l’IL-22 jouait un rôle pro-inflammatoire au cours de l’induction de l’asthme allergique puisque les souris déficientes en IL-22 développent une forme atténuée de la maladie. A l’inverse, nous avons constaté que l’IL-22 avait un effet protecteur dans la phase effectrice, et que cet effet était dépendant de l’IL-17A. Nos travaux mettent donc en lumière une double fonction de l’IL-22 dans l’asthme allergique chez la souris. En parallèle de ce travail, nous nous sommes intéressés au rôle de l’IL-1 et de l’inflammasome NLRP3 dans ce même modèle d’inflammation pulmonaire. Enfin, une troisième étude a permis de mettre en lumière un rôle encore inconnu de l’interleukine-33 dans l’activation des cellules dendritiques au cours de la mise en place de la réponse asthmatique. / Asthma is a heterogenous inflammatory disorder of the airways characterized by chronic airway inflammation, airway hyper-reactivity and by symptoms of recurrent wheezing, coughing and shortness breath. Understanding of the role of allergy and Th2 cells in asthma has benefited from mouse model of allergic asthma. Recently, several studies highlighted Th17 involvement in asthma pathogenesis. In the present study, we investigate the role of IL-22, a Th17-related cytokine, in a mouse model of allergic lung inflammation induced by ovalbumin. First, using IL-22 deficient mice, we demonstrated a pro-inflammatory role of IL-22 during the sensitization phase. In contrast, we observed a protective function of IL-22 during the effective phase. This protective effect of IL-22 seems to be dependent of IL-17. In conclusion, we demonstrate here a dual role of IL-22 in asthma pathogenesis. Since interleukin-1_ is critical for Th17 polarization in human, we also investigated the role of IL-1 signalling and NLRP3 inflammasome in our model of allergic airway inflammation. We showed that NLRP3 inflammasome and IL-1R/IL-1 pathway are critical to induce allergic lung inflammation, even in the absence of adjuvant. Finally, we studied the effect of interleukin-33 on dendritic cells activation and Th2 priming during antigen sensitization and in established asthma.
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Anti-IL17 na modulação da mecânica pulmonar, inflamação, estresse oxidativo e remodelamento da matriz extracelular em camundongos com inflamação pulmonar alérgica crônica exarcebada pelo LPS / Anti-IL17 in the modulation of pulmonary mechanics, inflammation, oxidative stress and remodeling of the extracellular matrix in mice with chronic allergic pulmonary inflammation exacerbated by LPS

Aristóteles, Luciana Ritha de Cassia Rolim Barbosa 24 August 2018 (has links)
Introdução: As citocinas de perfil Th17 parecem exercer um papel importante na fisiopatogenia da inflamação pulmonar alérgica crônica, embora sua exata influência seja incerta. Estudos demonstram uma influência destas citocinas em modular a resposta inflamatória e infecciosa. É importante enfatizar que a infecção é um dos responsáveis por perpetuar a resposta inflamatória crônica na asma, particularmente durante as exacerbações. Muitos dos efeitos desta via ainda não foram investigados em modelos de inflamação alérgica pulmonar crônica (asma) exarcebada pelo lipopolissacarídeos (LPS). Objetivos: Avaliar os efeitos do tratamento com anti-IL-17 em um modelo de inflamação pulmonar alérgica crônica exarcebada pelo LPS. Métodos: Camundongos BALB/c foram submetidos ao protocolo de indução alérgica crônica das vias aéreas com ovoalbumina ou salina e com posterior desafios inalatórios por 28 dias. Nos 1° e 14° dias um grupo (grupo OVA) recebeu ovoalbumina 50 mg em hidróxido de alumínio 6mg em um volume total de 0,2 ml por via intraperitoneal. Do 22° ao 28° dia, os animais receberam em dias alternados, inalação de aerossol de OVA diluída em NaCl 0,9% (soro fisiológico) na concentração de 10 mg/ml (1%) por 30 minutos. Ao mesmo tempo, o grupo controle (grupo SAL) recebeu solução salina (NaCl 0,9%) e hidróxido de alumínio (6 mg) por via intraperitoneal e nos dias dos desafios inalatórios foram expostos ao aerossol de solução salina 0,9% também por 30 minutos. Uma hora antes da inalação de ovoalbumina ou de salina, o anticorpo neutralizador anti-IL17 foi administrado por via intraperitoneal (ip) (grupos OVA-antiIL17 e SAL-antiIL17). Vinte e quatro horas antes do final do protocolo experimental (28° dia) um grupo de animais (grupo OVA-LPS) recebeu instilação traqueal de LPS (20 ?l de PBS + 0,1 mg / ml de Escherichia coli 0127: B8). O grupo sensibilizado que recebeu LPS e anti-IL17uma hora antes da exposição ao LPS foi chamado de OVA-LPS-antiIL17. No 29° dia do protocolo, os animais foram eutanasiados e inicialmente foram avaliadas as respostas máximas à metacolina da resistência e elastância do sistema respiratório. Os pulmões foram retirados e realizados as análises histológicas e morfométricas para avaliar a expressão celular de CD4+, CD8+, células dendríticas e células reguladoras T FOXP3; RT-PCR para arginase 1, transportador vesicular de acetilcolina (VAChT) e IL-17; ativação do fator de transcrição nuclear ?B (NF-?B); o número de células positivas para ROCK 1 e ROCK 2; resposta inflamatória de perfis Th1 (IL-2, IL-6, e TNF-alfa), Th2 (IL-4, IL-5, IL-10 e IL-13), Th-17 (IL-17), quimiocinas CCL17/TARC e CCL11/Eotaxina; resposta de remodelamento da matriz extracelular (conteúdo de fibras colágenas tipos I e III, decorina, lumican, biglicano, fibronectina, actina, TGFbeta1, o número de células positivas para MMP-9, MMP-12 e TIMP-1), e a resposta de estresse oxidativo (o número de células positivas para iNOS e conteúdo de isoprostano PGF2alfa e Arginase 1). Além disso, avaliamos por reação em cadeia da polimerase em tempo real (Real-time PCR) a expressão gênica de IL-17 e mRNA para VAChT As análises estatísticas foram realizada por meio do programa SigmaStat (Jandel Scientific, San Rafael, CA), onde um p < 0,05 será considerado estatisticamente significativo. Resultados: O grupo OVA-LPS-antíIL17 apresentou uma diminuição na resposta máxima pós metacolina de elastância e resistência do sistema respiratório, NO exalado, o número de células positivas para CD4+ e CD8+, células dendríticas, células T reguladoras FOXP3, mRNA para VAChT, NF-?B, ROCK1 e 2, quimiocinas CCL17 / TARC, e CCL11 / eotaxina, IL2 IL4, IL5, IL6, IL10, IL13 e IL17 nas paredes das vias aéreas comparado aos grupos OVA e OVA-LPS (p < 0,05). Alem disso, o tratamento com anti-IL17 reduziu o remodelamento brônquico (conteúdo de fibras colágenas I e III, decorina, lumican, biglican e fibronectina nas paredes das vias aéreas) assim como o número de células positivas para TGFbeta1, MMP-9, MMP12 e TIMP-1 ao redor das vias aéreas em comparação ao grupo SAL (p < 0.05). Houve também a atenuação de todos os parâmetros exceto no grupo OVA-antiIL17 em comparação ao grupo OVA (p < 0.05). Quanto ao estresse oxidativo o tratamento com o anti-IL17 também foi efetivo. Observamos redução de expressão celular de iNOS, conteúdo de PGF2alfa e expressão gênica de arginase1 em comparação com os grupos OVA e OVA-LPS (p < 0,05). Ainda, observamos uma atenuação do antí-IL17 na expressão gênica de IL17 e VAChT. Conclusões: A inibição da IL17 contribuiu para o controle da hiperresponsividade brônquica, da inflamação Th1/Th2/Th17, da expressão de quimiocinas, do remodelamento da matriz extracelular e da resposta da via NO-arginase, do sistema colinérgico sinalizado pela avaliação do VAChT e de estresse oxidativo no modelo de asma experimental. No modelo de asma experimental exarcebado pelo LPS houve potencialização das respostas de hiperresponsividade das vias aéreas distais, assim como da maioria dos marcadores de resposta inflamatória, de remodelamento da matriz extracelular e da ativação das vias via NO-arginase e do estresse oxidativo. O tratamento com anti-IL17 nesses animais foi capaz de controlar a maior parte das alterações citadas, exceto o conteúdo de actina. Dentre os mecanismos envolvidos no controle pelo tratamento com anti-IL17 das alterações estudadas no modelo de asma experimental exarcebado pelo LPS observamos a importância da expressão do fator de transcrição NFkb e de Rho quinase 1, e expressão gênica mRNA para VAChT. Embora outros mecanismos possam estar envolvidos e doses repetidas de anti-IL17 nos animais com asma exarcebado pelo LPS também necessitem ser testadas, o tratamento com anti-IL17 se mostrou uma ferramenta farmacológica importante para o tratamento das alterações, que à semelhança do observado nestes modelos experimentais, também se observam em pacientes com asma grave mesmo associada a quadros infecciosos agudos / Introduction: Th17 cytokines appear to play an important role in the pathophysiology of chronic allergic pulmonary inflammation, although their exact role is uncertain. Studies have demonstrated an influence of these cytokines in modulating the inflammatory and infectious response. It is important to emphasize that infection is one of the factors responsible for perpetuating the chronic inflammatory response in asthma, particularly during exacerbations. Many of the effects of this pathway have not yet been investigated in models of chronic allergic lung inflammation (asthma) exacerbated by lipopolysaccharide (LPS). Objectives: To evaluate the effects of anti-IL17 treatment on a model of chronic allergic pulmonary inflammation exacerbated by LPS. Methods: BALB/c mice were submitted to protocol of chronic allergic induction of the airways with ovalbumin or saline and with subsequent inhaled challenges for 28 days. On days 1 and 14 a group (OVA group) received ovalbumin 50 mg in 6 mg aluminum hydroxide in a total volume of 0.2 ml intraperitoneally. From the 22 to the 28 day, the animals received, on alternate days, aerosol inhalation of OVA diluted in NaCl 0.9% (saline solution) at a concentration of 10 mg/ml (1%) for 30 minutes. At the same time, the control group (SAL group) received saline solution (NaCl 0.9%) and aluminum hydroxide (6 mg) intraperitoneally and on the days of the inhalation challenges were exposed to aerosol 0.9% saline solution for 30 minutes. One hour prior to inhalation of ovalbumin or saline, the anti-IL17 neutralizing antibody was administered i.p. (OVA-anti-IL-17 and SAL-anti-IL17 groups). Twenty-four hours before the end of the experimental protocol (28th day) one group of animals (OVA-LPS group) received LPS tracheal instillation (20 ul PBS + 0.1 mg/ml Escherichia coli 0127: B8). The sensitized group that received LPS and anti-IL17 an hour before exposure to LPS was called OVA-LPS-anti-IL-17. On the 29th day of the protocol, the animals were euthanized and initially the maximum methacholine responses of resistance and elastance of the respiratory system were evaluated. The lungs were removed and the histological and morphometric analysis were performed to evaluate the cell expression of CD4+, CD8+, dendritic cells and T regulatory cells FOXP3; RT-PCR for arginase 1, vesicular acetylcholine transporter (VAChT) and IL-17; activation of nuclear transcription factor KappaB (NFkb); the number of positive cells for ROCK 1 and ROCK 2; Th1 (IL-2, IL-6, and TNF-alpha), Th2 (IL-4, IL-5, IL-10 and IL-13), Th-17 (IL-17), CCL17 chemokines/TARC and CCL11 / Eotaxin; (content of collagen fibers types I and III, decorin, lumican, biglican, fibronectin, actin, TGFbeta1, number of cells positive for MMP-9, MMP-12 and TIMP-1), and the response of oxidative stress (the number of positive cells for iNOS and isoprostane content PGF2alpha and Arginase 1). In addition, we evaluated the gene expression of IL-17 and mRNA for VAChT by real-time PCR. Statistical analysys were performed using the SigmaStat program (Jandel Scientific, San Rafael, CA), where a p < 0.05 were considered statistically significant. Results: The OVA-LPS-anti-IL-17 group showed a decrease in post-methacholine maximal response of elastance and respiratory system resistance, exhaled NO, number of CD4 + and CD8 + positive cells, dendritic cells, FOXP3 regulatory T cells, mRNA for VAChT, (p < 0.05), and in the presence of a significant increase in the expression of IL-1, IL-6, IL-10, IL-13 and IL17 in the airway walls compared to OVA and OVA-LPS (p < 0,05). In addition, anti-IL17 treatment reduced bronchial remodeling (content of collagen fibers I and III, decorin, lumican, biglican and fibronectin in the airway walls) as well as the number of TGFbeta1, MMP-9, MMP-12 and TIMP-1 around the airways compared to the SAL group (p < 0.05). There was also attenuation of all parameters except in the OVA-antiIL17 group compared to the OVA group (p < 0.05). As for oxidative stress, treatment with anti-IL17 was also effective. We observed reduction of iNOS cell expression, PGF2alpha content and arginase1 gene expression in comparison to OVA and OVA-LPS groups (p < 0.05). Furthermore, we observed an attenuation of the anti-IL17 in the IL17 and VAChT gene expression. Conclusions: Inhibition of IL-17 contributed to the control of bronchial hyperresponsiveness, Th1/Th2/Th17 inflammation, chemokine expression, extracellular matrix remodeling and NO-arginase pathway response, cholinergic system signaled by VAChT and of oxidative stress in the experimental asthma model. In the model of experimental asthma exacerbated by LPS there was a potentation of hyperresponsiveness responses of the distal airways, as well as of the majority of inflammatory response markers, extracellular matrix remodeling and activation of the pathways via NO-arginase and oxidative stress. Treatment with anti-IL-17 in these animals was able to control most of the above-mentioned changes, except the actin content. Among the mechanisms involved in the control by anti-IL17 treatment of the alterations studied in the model of experimental asthma exacerbated by LPS, we observed the importance of the expression of the transcription factor NF-Kappa B and Rho kinase 1, and gene expression mRNA for VAChT. Although other mechanisms may be involved and repeated doses of anti-IL17 in animals with LPS-exacerbated asthma also need to be tested, treatment with anti-IL17 has proved to be an important pharmacological tool for the treatment of the changes, which similar to those observed in these experimental models, are also seen in patients with severe asthma associated with acute infectious conditions
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O receptor de reconhecimento de patógenos TLR-2 e a proteína adaptadora MYD88 apresentam um importante papel na infecção murina contra o Paracoccidioides brasiliensis / The pathogen recognition receptor TLR-2 and the adaptor protein MyD88 have an important role in the innate and adaptive immunity against Paracoccidioides brasiliensis infection

Loures, Flávio Vieira 08 March 2010 (has links)
Os mecanismos imunológicos que governam a interação entre o fungo Paracoccidioides brasiliensis e o hospedeiro têm sido pouco estudados. Tanto os componentes do fungo como os receptores dos fagócitos envolvidos nesta interação são pouco conhecidos. Baseados nestes fatos, nosso trabalho teve por objetivo caracterizar in vitro e in vivo o envolvimento do receptor Toll Like-2 (TLR-2) e da proteína adaptadora MyD88 (myeloid differentiation primary response gene 88) na infecção de camundongos pelo P. brasiliensis. O TLR-2 é um receptor da imunidade inata envolvido no reconhecimento de PAMPs (padrões moleculares associados aos patógenos), enquanto que MyD88 é uma molécula envolvida na sinalização celular induzida por muitos TLRs e que culmina com a ativação de vários fatores de transcrição, entre eles o NFB, envolvidos na ativação de genes ligados à resposta inflamatória. Para tanto, utilizamos camundongos C57Bl/6 deficientes e normais para TLR-2 e para MyD88. Demonstramos que, comparado ao grupo controle, animais TLR2-/- apresentavam uma infecção pulmonar menos grave associada com menor síntese de óxido nítrico (NO). Resultados equivalentes foram obtidos com macrófagos peritoneais e alveolares infectados in vitro. Inesperadamente, apesar das diferenças na carga fúngica, ambas as linhagens apresentavam tempo médio de sobrevida semelhante e lesões pulmonares de gravidade equivalente. Os estudos com leucócitos infiltrantes de pulmão revelaram um aumento de leucócitos polimorfonucleares neutrófilos (PMNs) nos animais TLR-2-/- associado com um menor número de linfócitos TCD4+ e TCD8+ ativados. Animais TLR-2-/- deficientes apresentaram uma discreta diferença quanto à síntese de citocinas pulmonares dos tipos Th1 e Th2, porém estes animais apresentaram maiores níveis de KC, uma quimiocina CXC envolvida na quimiotaxia de neutrófilos, assim com maiores níveis de citocinas Th17 (IL-6, IL-17, IL-23 e TGF-). Além disso, a resposta imune Th17 desenvolvida por animais TLR-2-/- esteve associada com menor expansão de células T regulatórias CD4+CD25+FoxP3+. Assim, o TLR-2 controla a imunidade inata e adaptativa frente ao P. brasiliensis e regula negativamente a resposta imune Th17 e a patologia pulmonar. Em relação aos estudos com animais deficientes para a proteína adaptadora MyD88 na paracoccidioimicose verificamos que sua ausência resultou numa produção deficiente in vitro e in vivo de NO, além de uma produção deficiente in vivo de citocinas do tipo Th1, Th2 e Th17. Animais MyD88-deficientes infectados desenvolveram uma resposta imune prejudicada, evidenciada pelo menor número de macrófagos ativados, assim como uma imunidade adaptativa menos eficiente, evidenciada pelo menor número de células T CD4 ativadas que afluíram aos pulmões. Este quadro culminou com uma carga fúngica maior nos pulmões dos animais MyD88- deficientes, como também permitiu uma exuberante disseminação do fungo para outros órgãos, como fígado e baço. Os pulmões e o fígado apresentaram graves lesões com a presença de granulomas coalescentes e ricos agregados fúngicos. Assim, camundongos MyD88-deficientes não foram capazes de controlar a doença e morreram em um tempo mais curto que os animais MyD88-competentes, como evidenciado em experimentos de sobrevida. Assim, nossos achados demonstram que a sinalização intracelular mediada pela proteína MyD88 é importante para a ativação dos mecanismos fungicidas, assim como para a ativação das respostas imunes inata e adaptativa contra o P. brasiliensis. Em conjunto, nosso trabalho demonstra que tanto o TLR-2 quanto a molécula adaptadora MyD88 desempenham um papel relevante no controle da infecção, assim como na indução da resposta imune contra este patógeno fúngico primário. / The immunological mechanisms that govern the interaction between hosts and the dimorphic fungus Paracoccidioides brasiliensis have been scarcely studied. Both, fungal and phagocyte receptors involved in this interaction are poorly understood. Based on these facts, the aim of our study was to characterize in vitro and in vivo the role played by Toll Like Receptor-2 (TLR-2) and the adaptor protein MyD88 (myeloid differentiation primary response gene 88) in murine pulmonary paracoccidioidomycosis. The TLR-2 is a receptor of innate immunity involved in the recognition of PAMPs (pathogen associated molecular patterns), whereas MyD88 is a molecule involved in cell signaling induced by many TLRs . TLR-mediated activation results in the production of several nuclear transcription factors, including NFB, which activate important genes of the inflammatory response. Wild-type (WT) besides TLR- 2- and MyD88-deficient C57Bl/6 mice were used in our investigation. We showed that, compared to control animals, TLR2-/- mice developed a less severe pulmonary infection associated with reduced synthesis of nitric oxide (NO). Equivalent results were obtained with in vitro infected peritoneal and alveolar macrophages. Unexpectedly, despite the differences in fungal loads, TLR-2-/- and WT mice showed equivalent survival times and pulmonary lesions. Studies with lung infiltrating leukocytes revealed an increase of polymorphonuclear neutrophil leukocytes (PMNs) in TLR-2-/- mice associated with a low number of activated T CD4 and T CD8+ lymphocytes. Compared with WT mice, the TLR-2-deficient mice showed slight differences in the production of pulmonary Th1 and Th2 cytokines, but presented higher levels of KC, a CXC chemokine involved in neutrophil chemotaxis, besides increased levels of Th17 cytokines ( IL-6, IL-17, IL-23 and TGF-). Furthermore, the prevalent Th17 immune response developed by TLR-2-/- mice was associated with lower expansion of regulatory T cells CD4+CD25+FoxP3+. Thus, TLR-2 controls the innate and adaptive immunity against the P. brasiliensis infection and negatively regulates Th17 immune response and pulmonary pathology. Studies with MyD88-deficient mice showed an impaired production of NO in vivo and in vitro, and a deficient in vivo production of Th1, Th2 and Th17 cytokines. In addition, infected MyD88-deficient mice developed an impaired immune response, evidenced by poorly activated macrophages, as well as by an inefficient adaptive immunity mediated by a diminished influx of activated CD4+ T cells to the lungs. These events led to increased fungal loads in the lungs of MyD88-deficient mice and allowed a marked dissemination of the fungus to other organs such as liver and spleen, which presented severe lesions composed by coalescent granulomas containing high numbers of fungal cells. As consequence, MyD88-deficient mice were unable to control fungal growth and presented a decreased survival time. Our findings demonstrate that MyD88 signaling is important to the activation of fungicidal mechanisms and to the induction of the innate and adaptive immunity against P. brasiliensis. Altogether, our work shows that both TLR-2 and the adapter molecule MyD88, play an important role in controlling of P. brasiliensis infection, as well as in the induction of immune responses against this primary fungal pathogen.
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Étude de la contribution des récepteurs activés par les proliférateurs de peroxysomes en physiopathologie articulaire / Peroxisome proliferator-actived receptors : contribution to articular-physiopathology

Koufany, Meriem 17 December 2015 (has links)
Les récepteurs activés par les proliférateurs de peroxysomes (PPARs) sont des facteurs de transcription impliqués dans la régulation du métabolisme lipidique et de la tolérance au glucose. Les PPARs contrôlent également l’inflammation associée à de multiples pathologies, dont la polyarthrite rhumatoide. Dans les travaux présentés dans ce manuscrit, nous avons comparé les potentialités anti-arthritiques, dans un modèle expérimental, de deux agonistes synthétiques de haute affinité pour deux isotypes de PPARs, PPARα et PPARγ. Nous avons démontré qu’un traitement avec un agoniste sélectif de PPARγ, la pioglitazone, en plus de diminuer la sévérité de l’arthrite expérimentale, réduisait la perte osseuse inflammatoire en préservant la micro-architecture osseuse. Nous avons mis en évidence que PPARγ, d’une part, régulait l’expression locale et systémique de l’interleukine-17 et de RANKL, et que, d’autre part, il inhibait l’expression du facteur de transcription RORγt, acteur majeur de la voie IL-17/Th17. Les animaux déficients pour PPARγ nous ont permis de confirmer son rôle majeur dans le développement du processus arthritique. En effet, ces animaux présentent tous et de façon spontanée une arthrite associée à une augmentation du nombre de mastocytes capables de produire l’IL-17 et leur propre facteur de différenciation, le SCF dans la synoviale inflammatoire. Enfin, nous avons discuté le lien possible entre l'arthrite inflammatoire et la mastocytose à la lumière de l’étude d’un cas clinique d’un patient atteint de polyarthrite rhumatoïde concomitante à une mastocytose systémique / Peroxisome proliferator-activated receptors (PPARs) are transcription factors implicated in lipid metabolism and glucose tolerance. Once activated by specific agonists, PPARs control inflammation associated with numerous diseases, notably Rheumatoid arthritis. The first study presented here aim to compare the anti-arthritic potency of two high-affinity synthetic agonists for PPARα and PPARγ in an experimental model. Then we focused on the effect of pioglitazone, a high-affinity synthetic agonists for PPARγ, and demonstrated that a per os treatment with this agonist not only reduced experimental arthritis but also inhibited partly inflammation-related bone loss by preserving bone microarchitecture. We pointed out that PPARγ, on one hand, regulated local and systemic expression of interleukine-17 (IL-17) and RANKL and on the other hand, inhibited expression of transcription factor RORγt, a main regulator of IL-17/Th17 pathway. Study of mice deficient for PPARγ confirmed its major role in the development of the arthritic process since these mice developed spontaneously arthritis. Of interest arthritis in these mice is associated with increased number of synovial mast cells able to produce IL-17 and their own differenciation factor, the SCF. Finally, we discussed the possible link between inflammatory arthritis and mastocytosis in a case report of a patient suffering from rheumatoid arthritis concomitant to systemic mastocytosis
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Anti-IL17 na modulação da mecânica pulmonar, inflamação, estresse oxidativo e remodelamento da matriz extracelular em camundongos com inflamação pulmonar alérgica crônica exarcebada pelo LPS / Anti-IL17 in the modulation of pulmonary mechanics, inflammation, oxidative stress and remodeling of the extracellular matrix in mice with chronic allergic pulmonary inflammation exacerbated by LPS

Luciana Ritha de Cassia Rolim Barbosa Aristóteles 24 August 2018 (has links)
Introdução: As citocinas de perfil Th17 parecem exercer um papel importante na fisiopatogenia da inflamação pulmonar alérgica crônica, embora sua exata influência seja incerta. Estudos demonstram uma influência destas citocinas em modular a resposta inflamatória e infecciosa. É importante enfatizar que a infecção é um dos responsáveis por perpetuar a resposta inflamatória crônica na asma, particularmente durante as exacerbações. Muitos dos efeitos desta via ainda não foram investigados em modelos de inflamação alérgica pulmonar crônica (asma) exarcebada pelo lipopolissacarídeos (LPS). Objetivos: Avaliar os efeitos do tratamento com anti-IL-17 em um modelo de inflamação pulmonar alérgica crônica exarcebada pelo LPS. Métodos: Camundongos BALB/c foram submetidos ao protocolo de indução alérgica crônica das vias aéreas com ovoalbumina ou salina e com posterior desafios inalatórios por 28 dias. Nos 1° e 14° dias um grupo (grupo OVA) recebeu ovoalbumina 50 mg em hidróxido de alumínio 6mg em um volume total de 0,2 ml por via intraperitoneal. Do 22° ao 28° dia, os animais receberam em dias alternados, inalação de aerossol de OVA diluída em NaCl 0,9% (soro fisiológico) na concentração de 10 mg/ml (1%) por 30 minutos. Ao mesmo tempo, o grupo controle (grupo SAL) recebeu solução salina (NaCl 0,9%) e hidróxido de alumínio (6 mg) por via intraperitoneal e nos dias dos desafios inalatórios foram expostos ao aerossol de solução salina 0,9% também por 30 minutos. Uma hora antes da inalação de ovoalbumina ou de salina, o anticorpo neutralizador anti-IL17 foi administrado por via intraperitoneal (ip) (grupos OVA-antiIL17 e SAL-antiIL17). Vinte e quatro horas antes do final do protocolo experimental (28° dia) um grupo de animais (grupo OVA-LPS) recebeu instilação traqueal de LPS (20 ?l de PBS + 0,1 mg / ml de Escherichia coli 0127: B8). O grupo sensibilizado que recebeu LPS e anti-IL17uma hora antes da exposição ao LPS foi chamado de OVA-LPS-antiIL17. No 29° dia do protocolo, os animais foram eutanasiados e inicialmente foram avaliadas as respostas máximas à metacolina da resistência e elastância do sistema respiratório. Os pulmões foram retirados e realizados as análises histológicas e morfométricas para avaliar a expressão celular de CD4+, CD8+, células dendríticas e células reguladoras T FOXP3; RT-PCR para arginase 1, transportador vesicular de acetilcolina (VAChT) e IL-17; ativação do fator de transcrição nuclear ?B (NF-?B); o número de células positivas para ROCK 1 e ROCK 2; resposta inflamatória de perfis Th1 (IL-2, IL-6, e TNF-alfa), Th2 (IL-4, IL-5, IL-10 e IL-13), Th-17 (IL-17), quimiocinas CCL17/TARC e CCL11/Eotaxina; resposta de remodelamento da matriz extracelular (conteúdo de fibras colágenas tipos I e III, decorina, lumican, biglicano, fibronectina, actina, TGFbeta1, o número de células positivas para MMP-9, MMP-12 e TIMP-1), e a resposta de estresse oxidativo (o número de células positivas para iNOS e conteúdo de isoprostano PGF2alfa e Arginase 1). Além disso, avaliamos por reação em cadeia da polimerase em tempo real (Real-time PCR) a expressão gênica de IL-17 e mRNA para VAChT As análises estatísticas foram realizada por meio do programa SigmaStat (Jandel Scientific, San Rafael, CA), onde um p < 0,05 será considerado estatisticamente significativo. Resultados: O grupo OVA-LPS-antíIL17 apresentou uma diminuição na resposta máxima pós metacolina de elastância e resistência do sistema respiratório, NO exalado, o número de células positivas para CD4+ e CD8+, células dendríticas, células T reguladoras FOXP3, mRNA para VAChT, NF-?B, ROCK1 e 2, quimiocinas CCL17 / TARC, e CCL11 / eotaxina, IL2 IL4, IL5, IL6, IL10, IL13 e IL17 nas paredes das vias aéreas comparado aos grupos OVA e OVA-LPS (p < 0,05). Alem disso, o tratamento com anti-IL17 reduziu o remodelamento brônquico (conteúdo de fibras colágenas I e III, decorina, lumican, biglican e fibronectina nas paredes das vias aéreas) assim como o número de células positivas para TGFbeta1, MMP-9, MMP12 e TIMP-1 ao redor das vias aéreas em comparação ao grupo SAL (p < 0.05). Houve também a atenuação de todos os parâmetros exceto no grupo OVA-antiIL17 em comparação ao grupo OVA (p < 0.05). Quanto ao estresse oxidativo o tratamento com o anti-IL17 também foi efetivo. Observamos redução de expressão celular de iNOS, conteúdo de PGF2alfa e expressão gênica de arginase1 em comparação com os grupos OVA e OVA-LPS (p < 0,05). Ainda, observamos uma atenuação do antí-IL17 na expressão gênica de IL17 e VAChT. Conclusões: A inibição da IL17 contribuiu para o controle da hiperresponsividade brônquica, da inflamação Th1/Th2/Th17, da expressão de quimiocinas, do remodelamento da matriz extracelular e da resposta da via NO-arginase, do sistema colinérgico sinalizado pela avaliação do VAChT e de estresse oxidativo no modelo de asma experimental. No modelo de asma experimental exarcebado pelo LPS houve potencialização das respostas de hiperresponsividade das vias aéreas distais, assim como da maioria dos marcadores de resposta inflamatória, de remodelamento da matriz extracelular e da ativação das vias via NO-arginase e do estresse oxidativo. O tratamento com anti-IL17 nesses animais foi capaz de controlar a maior parte das alterações citadas, exceto o conteúdo de actina. Dentre os mecanismos envolvidos no controle pelo tratamento com anti-IL17 das alterações estudadas no modelo de asma experimental exarcebado pelo LPS observamos a importância da expressão do fator de transcrição NFkb e de Rho quinase 1, e expressão gênica mRNA para VAChT. Embora outros mecanismos possam estar envolvidos e doses repetidas de anti-IL17 nos animais com asma exarcebado pelo LPS também necessitem ser testadas, o tratamento com anti-IL17 se mostrou uma ferramenta farmacológica importante para o tratamento das alterações, que à semelhança do observado nestes modelos experimentais, também se observam em pacientes com asma grave mesmo associada a quadros infecciosos agudos / Introduction: Th17 cytokines appear to play an important role in the pathophysiology of chronic allergic pulmonary inflammation, although their exact role is uncertain. Studies have demonstrated an influence of these cytokines in modulating the inflammatory and infectious response. It is important to emphasize that infection is one of the factors responsible for perpetuating the chronic inflammatory response in asthma, particularly during exacerbations. Many of the effects of this pathway have not yet been investigated in models of chronic allergic lung inflammation (asthma) exacerbated by lipopolysaccharide (LPS). Objectives: To evaluate the effects of anti-IL17 treatment on a model of chronic allergic pulmonary inflammation exacerbated by LPS. Methods: BALB/c mice were submitted to protocol of chronic allergic induction of the airways with ovalbumin or saline and with subsequent inhaled challenges for 28 days. On days 1 and 14 a group (OVA group) received ovalbumin 50 mg in 6 mg aluminum hydroxide in a total volume of 0.2 ml intraperitoneally. From the 22 to the 28 day, the animals received, on alternate days, aerosol inhalation of OVA diluted in NaCl 0.9% (saline solution) at a concentration of 10 mg/ml (1%) for 30 minutes. At the same time, the control group (SAL group) received saline solution (NaCl 0.9%) and aluminum hydroxide (6 mg) intraperitoneally and on the days of the inhalation challenges were exposed to aerosol 0.9% saline solution for 30 minutes. One hour prior to inhalation of ovalbumin or saline, the anti-IL17 neutralizing antibody was administered i.p. (OVA-anti-IL-17 and SAL-anti-IL17 groups). Twenty-four hours before the end of the experimental protocol (28th day) one group of animals (OVA-LPS group) received LPS tracheal instillation (20 ul PBS + 0.1 mg/ml Escherichia coli 0127: B8). The sensitized group that received LPS and anti-IL17 an hour before exposure to LPS was called OVA-LPS-anti-IL-17. On the 29th day of the protocol, the animals were euthanized and initially the maximum methacholine responses of resistance and elastance of the respiratory system were evaluated. The lungs were removed and the histological and morphometric analysis were performed to evaluate the cell expression of CD4+, CD8+, dendritic cells and T regulatory cells FOXP3; RT-PCR for arginase 1, vesicular acetylcholine transporter (VAChT) and IL-17; activation of nuclear transcription factor KappaB (NFkb); the number of positive cells for ROCK 1 and ROCK 2; Th1 (IL-2, IL-6, and TNF-alpha), Th2 (IL-4, IL-5, IL-10 and IL-13), Th-17 (IL-17), CCL17 chemokines/TARC and CCL11 / Eotaxin; (content of collagen fibers types I and III, decorin, lumican, biglican, fibronectin, actin, TGFbeta1, number of cells positive for MMP-9, MMP-12 and TIMP-1), and the response of oxidative stress (the number of positive cells for iNOS and isoprostane content PGF2alpha and Arginase 1). In addition, we evaluated the gene expression of IL-17 and mRNA for VAChT by real-time PCR. Statistical analysys were performed using the SigmaStat program (Jandel Scientific, San Rafael, CA), where a p < 0.05 were considered statistically significant. Results: The OVA-LPS-anti-IL-17 group showed a decrease in post-methacholine maximal response of elastance and respiratory system resistance, exhaled NO, number of CD4 + and CD8 + positive cells, dendritic cells, FOXP3 regulatory T cells, mRNA for VAChT, (p < 0.05), and in the presence of a significant increase in the expression of IL-1, IL-6, IL-10, IL-13 and IL17 in the airway walls compared to OVA and OVA-LPS (p < 0,05). In addition, anti-IL17 treatment reduced bronchial remodeling (content of collagen fibers I and III, decorin, lumican, biglican and fibronectin in the airway walls) as well as the number of TGFbeta1, MMP-9, MMP-12 and TIMP-1 around the airways compared to the SAL group (p < 0.05). There was also attenuation of all parameters except in the OVA-antiIL17 group compared to the OVA group (p < 0.05). As for oxidative stress, treatment with anti-IL17 was also effective. We observed reduction of iNOS cell expression, PGF2alpha content and arginase1 gene expression in comparison to OVA and OVA-LPS groups (p < 0.05). Furthermore, we observed an attenuation of the anti-IL17 in the IL17 and VAChT gene expression. Conclusions: Inhibition of IL-17 contributed to the control of bronchial hyperresponsiveness, Th1/Th2/Th17 inflammation, chemokine expression, extracellular matrix remodeling and NO-arginase pathway response, cholinergic system signaled by VAChT and of oxidative stress in the experimental asthma model. In the model of experimental asthma exacerbated by LPS there was a potentation of hyperresponsiveness responses of the distal airways, as well as of the majority of inflammatory response markers, extracellular matrix remodeling and activation of the pathways via NO-arginase and oxidative stress. Treatment with anti-IL-17 in these animals was able to control most of the above-mentioned changes, except the actin content. Among the mechanisms involved in the control by anti-IL17 treatment of the alterations studied in the model of experimental asthma exacerbated by LPS, we observed the importance of the expression of the transcription factor NF-Kappa B and Rho kinase 1, and gene expression mRNA for VAChT. Although other mechanisms may be involved and repeated doses of anti-IL17 in animals with LPS-exacerbated asthma also need to be tested, treatment with anti-IL17 has proved to be an important pharmacological tool for the treatment of the changes, which similar to those observed in these experimental models, are also seen in patients with severe asthma associated with acute infectious conditions
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Amino terminal region of FOXP3 coordinates the regulation of transcriptional targets in regulatory and effector T cell lineages /

Lopes, Jared Emery. January 2007 (has links)
Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (p. 133-145).
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O receptor de reconhecimento de patógenos TLR-2 e a proteína adaptadora MYD88 apresentam um importante papel na infecção murina contra o Paracoccidioides brasiliensis / The pathogen recognition receptor TLR-2 and the adaptor protein MyD88 have an important role in the innate and adaptive immunity against Paracoccidioides brasiliensis infection

Flávio Vieira Loures 08 March 2010 (has links)
Os mecanismos imunológicos que governam a interação entre o fungo Paracoccidioides brasiliensis e o hospedeiro têm sido pouco estudados. Tanto os componentes do fungo como os receptores dos fagócitos envolvidos nesta interação são pouco conhecidos. Baseados nestes fatos, nosso trabalho teve por objetivo caracterizar in vitro e in vivo o envolvimento do receptor Toll Like-2 (TLR-2) e da proteína adaptadora MyD88 (myeloid differentiation primary response gene 88) na infecção de camundongos pelo P. brasiliensis. O TLR-2 é um receptor da imunidade inata envolvido no reconhecimento de PAMPs (padrões moleculares associados aos patógenos), enquanto que MyD88 é uma molécula envolvida na sinalização celular induzida por muitos TLRs e que culmina com a ativação de vários fatores de transcrição, entre eles o NFB, envolvidos na ativação de genes ligados à resposta inflamatória. Para tanto, utilizamos camundongos C57Bl/6 deficientes e normais para TLR-2 e para MyD88. Demonstramos que, comparado ao grupo controle, animais TLR2-/- apresentavam uma infecção pulmonar menos grave associada com menor síntese de óxido nítrico (NO). Resultados equivalentes foram obtidos com macrófagos peritoneais e alveolares infectados in vitro. Inesperadamente, apesar das diferenças na carga fúngica, ambas as linhagens apresentavam tempo médio de sobrevida semelhante e lesões pulmonares de gravidade equivalente. Os estudos com leucócitos infiltrantes de pulmão revelaram um aumento de leucócitos polimorfonucleares neutrófilos (PMNs) nos animais TLR-2-/- associado com um menor número de linfócitos TCD4+ e TCD8+ ativados. Animais TLR-2-/- deficientes apresentaram uma discreta diferença quanto à síntese de citocinas pulmonares dos tipos Th1 e Th2, porém estes animais apresentaram maiores níveis de KC, uma quimiocina CXC envolvida na quimiotaxia de neutrófilos, assim com maiores níveis de citocinas Th17 (IL-6, IL-17, IL-23 e TGF-). Além disso, a resposta imune Th17 desenvolvida por animais TLR-2-/- esteve associada com menor expansão de células T regulatórias CD4+CD25+FoxP3+. Assim, o TLR-2 controla a imunidade inata e adaptativa frente ao P. brasiliensis e regula negativamente a resposta imune Th17 e a patologia pulmonar. Em relação aos estudos com animais deficientes para a proteína adaptadora MyD88 na paracoccidioimicose verificamos que sua ausência resultou numa produção deficiente in vitro e in vivo de NO, além de uma produção deficiente in vivo de citocinas do tipo Th1, Th2 e Th17. Animais MyD88-deficientes infectados desenvolveram uma resposta imune prejudicada, evidenciada pelo menor número de macrófagos ativados, assim como uma imunidade adaptativa menos eficiente, evidenciada pelo menor número de células T CD4 ativadas que afluíram aos pulmões. Este quadro culminou com uma carga fúngica maior nos pulmões dos animais MyD88- deficientes, como também permitiu uma exuberante disseminação do fungo para outros órgãos, como fígado e baço. Os pulmões e o fígado apresentaram graves lesões com a presença de granulomas coalescentes e ricos agregados fúngicos. Assim, camundongos MyD88-deficientes não foram capazes de controlar a doença e morreram em um tempo mais curto que os animais MyD88-competentes, como evidenciado em experimentos de sobrevida. Assim, nossos achados demonstram que a sinalização intracelular mediada pela proteína MyD88 é importante para a ativação dos mecanismos fungicidas, assim como para a ativação das respostas imunes inata e adaptativa contra o P. brasiliensis. Em conjunto, nosso trabalho demonstra que tanto o TLR-2 quanto a molécula adaptadora MyD88 desempenham um papel relevante no controle da infecção, assim como na indução da resposta imune contra este patógeno fúngico primário. / The immunological mechanisms that govern the interaction between hosts and the dimorphic fungus Paracoccidioides brasiliensis have been scarcely studied. Both, fungal and phagocyte receptors involved in this interaction are poorly understood. Based on these facts, the aim of our study was to characterize in vitro and in vivo the role played by Toll Like Receptor-2 (TLR-2) and the adaptor protein MyD88 (myeloid differentiation primary response gene 88) in murine pulmonary paracoccidioidomycosis. The TLR-2 is a receptor of innate immunity involved in the recognition of PAMPs (pathogen associated molecular patterns), whereas MyD88 is a molecule involved in cell signaling induced by many TLRs . TLR-mediated activation results in the production of several nuclear transcription factors, including NFB, which activate important genes of the inflammatory response. Wild-type (WT) besides TLR- 2- and MyD88-deficient C57Bl/6 mice were used in our investigation. We showed that, compared to control animals, TLR2-/- mice developed a less severe pulmonary infection associated with reduced synthesis of nitric oxide (NO). Equivalent results were obtained with in vitro infected peritoneal and alveolar macrophages. Unexpectedly, despite the differences in fungal loads, TLR-2-/- and WT mice showed equivalent survival times and pulmonary lesions. Studies with lung infiltrating leukocytes revealed an increase of polymorphonuclear neutrophil leukocytes (PMNs) in TLR-2-/- mice associated with a low number of activated T CD4 and T CD8+ lymphocytes. Compared with WT mice, the TLR-2-deficient mice showed slight differences in the production of pulmonary Th1 and Th2 cytokines, but presented higher levels of KC, a CXC chemokine involved in neutrophil chemotaxis, besides increased levels of Th17 cytokines ( IL-6, IL-17, IL-23 and TGF-). Furthermore, the prevalent Th17 immune response developed by TLR-2-/- mice was associated with lower expansion of regulatory T cells CD4+CD25+FoxP3+. Thus, TLR-2 controls the innate and adaptive immunity against the P. brasiliensis infection and negatively regulates Th17 immune response and pulmonary pathology. Studies with MyD88-deficient mice showed an impaired production of NO in vivo and in vitro, and a deficient in vivo production of Th1, Th2 and Th17 cytokines. In addition, infected MyD88-deficient mice developed an impaired immune response, evidenced by poorly activated macrophages, as well as by an inefficient adaptive immunity mediated by a diminished influx of activated CD4+ T cells to the lungs. These events led to increased fungal loads in the lungs of MyD88-deficient mice and allowed a marked dissemination of the fungus to other organs such as liver and spleen, which presented severe lesions composed by coalescent granulomas containing high numbers of fungal cells. As consequence, MyD88-deficient mice were unable to control fungal growth and presented a decreased survival time. Our findings demonstrate that MyD88 signaling is important to the activation of fungicidal mechanisms and to the induction of the innate and adaptive immunity against P. brasiliensis. Altogether, our work shows that both TLR-2 and the adapter molecule MyD88, play an important role in controlling of P. brasiliensis infection, as well as in the induction of immune responses against this primary fungal pathogen.
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Etude de l’implication de l’axe IL-23/Th17 dans deux modèles physiopathologiques humains : la réponse à Mycoplasma hominis et la sclérodermie systémique / Study of the IL-23/Th17 axis involvement in two physiopathological human models : response to Mycoplasma hominis and systemic sclerosis

Truchetet, Marie-Élise 29 November 2012 (has links)
La nature du lien qui unit les deux aspects du système immunitaire, que sont la défense de l’hôte contre les agressions extérieures et la genèse des maladies auto- immunes, n’a pas été élucidée. L’axe IL-23/Th17 joue un rôle dans les deux versants, ce qui le place en bonne position pour être un potentiel chaînon manquant. Objectif : connaître l’implication de cet axe dans un modèle infectieux, Mycoplasma hominis, et un modèle de maladie auto-immune, la sclérodermie systémique (ScS), dans lesquels il n’a pas encore été étudié. Les lipoprotéines membranaires de M. hominis sont capables d’induire une maturation des cellules dendritiques humaines. Elle s’accompagne d’une sécrétion d’IL-23 variable selon l’origine clinique des isolats, via TLR2, et d’une polarisation vers la voie Th17. Nous avons observé une augmentation de la fréquence des cellules Th17 et Th22 dans le sang périphérique des patients ScS, potentialisée par l’iloprost, via entre autres la production monocytaire d’IL-23. Dans la peau des patients ScS, il existe une augmentation des cellules produisant l’IL-17 inversement corrélé au score de fibrose cutanée. In vitro, l’IL-17 est capable d’inhiber partiellement l’expression d’α-SMA induite par le TGF-ß et d’induire la sécrétion de MMP1 par des fibroblastes dermiques humains. L’axe IL-23/IL-17 et les cellules Th17 jouent un rôle dans la défense contre M. hominis et dans la physiopathologie de la ScS. / Relationship between both aspects of the immune system, ie host defense against external aggression and genesis of autoimmune diseases, has not been elucidated. IL-23/Th17 axis plays a role in both sides, which puts him in a good position to be a potential missing link. Objective: To understand the implication of this axis in a model of infection, Mycoplasma hominis, and a model of autoimmune disease, systemic sclerosis (SSc), in which it has not yet been studied.
The membrane lipoproteins of M. hominis are capable of inducing human dendritic cell maturation. It occurs along with an IL-23 secretion changing with the clinical origin of isolates, via TLR2, and a T cell polarization towards Th17. Then we observed an increase in the Th17 and Th22 cell frequency in peripheral blood of SSc patients, further enhanced by iloprost via monocyte production of IL-23 among others. In the skin of SSc patients, we showed an increase in IL-17-producing cells with an inverse correlation to the skin fibrosis score. In vitro, IL-17 is able to partially inhibit the expression of α-SMA induced by TGF-ß and to induce the secretion of MMP1 in human dermal fibroblasts. The IL-23/IL-17 axis and Th17 cells play a role in defense against M. hominis and in the pathogenesis of SSc.

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