Participation of Th1 and Th2 cytokines ischemia and reperfusion injury of kidney.

Author(s)

Vanessa Nunes de Paiva

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI)
• Defense date: 2008-12-12

Examining board members

Niels Olsen Saraiva Câmara; Sonia Jancar Negro; Álvaro Pacheco e Silva Filho

• Advisor: Niels Olsen Saraiva Câmara

Abstract

Renal ischemia/reperfusion injury (I/R) is the major cause of acute renal failure (ARF) in the native as well as in the transplanted kidneys, with a complex pathogenesis that involves many components of inflammatory response such as leukocyte infiltration and generation of inflammatory mediators by tubular cells. Recent evidences show a critical role of the CD4+ T cell, with the Th1/Th2 paradigm as a possible ejectors mechanism. The present study has the objective to investigate the participation of some main Th1 and Th2 cytokines in the development of the renal of I/R. For that, we developed an experimental model of renal I/R in deficient in IL-12, IFN-, double deficient IFN- and IL-12 (representing defect of the pathway Th1), IL-4 and IL-10 (representing defect of the pathway Th2) and in double deficient IL-10 and IL-12 knockout mice, having wild-type mice as controls. All animals were submitted to renal I/R by reversible ligation of the renal pedicles for 45 minutes followed by 24 hours of reperfusion. After induction of the ischemia, we analyzed renal function and morphometric histological analyzes. Furthermore, we quantified the expression of HO-1 (cytoprotection gene), t-bet (transcription factor involved in the differentiation Th1), GATA-3 (transcription factor involved in the differentiation Th2), and cytokine pro-inflammatory IL-6 and chemokine pro-inflammatory MCP-1, aiming to characterize the influence of Th1/Th2 polarization in the immune response driven by the renal I/R. We showed that the IL-4, IFN-, IL-10 and IL-10/IL-12-de_cient mice presented an important kidney dysfunction, characterized by higher levels serum creatinine and tubular necrosis, being comparable to the wild-type animals. The molecular analyses, utilizing the real-time PCR, showed a significantly higher expression of HO-1, IL-6, MCP-1 and transcription factor involved in the differentiation Th2 (GATA-3) in the in IL-4, IFN-, IL-10 and IL-10/IL-12-defficient mice, in comparison with the in IL-12, IFN-/IL-12-de_cient mice showed lower expression transcription factor involved in the differentiation Th1 (T-bet) . Moreover, the renal dysfunction seen in Th2-de_cient mice was followed by a higher expression of IL-6. When we make the transfer adoptive of bone marrow of animals deficient in IL-12 and IL-4 to wild animals previously with sublethal cell depletion, these animals produce similar results to animals deficient in IL-12 and IL-4, where the animals reconstituted wild animals with bone marrow IL-12 showed lower levels of serum urea and lower expression mRNA of IL-6, while the wild animals reconstituted with bone marrow of animals IL-4 showed higher levels of serum urea and greater expression of mRNA IL-6. These data show that really the cytokine IL-12 appears to be the main cytokine involved in the inflammatory process triggered by the injury of ischemia and reperfusion kidney. Such _ndings favor the hypothesis of the deleterious effects of Th1 cells with prole and the protective role of Th2 cells in ischemic renal injury. These novel insights may provide basis for the better pathophysiological understanding, as well as for development of preventive and therapeutic methods for the ischemic acute renal failure. (AU)

• FAPESP's process: 06/04029-0 - Th1 cellular response and its modulation in renal inflammatory injury secondary to ischemia and reperfusion
• Grantee: Vanessa Nunes de Paiva
• Support Opportunities: Scholarships in Brazil - Master