Th17 Cells Are Not Directly Associated with Renal Ischemia-Reperfusion Injury

Abstract

Purpose: Interleukin-17-producing T cell (Th17 cell) is a newly discovered subtype of helper T cell. Its function and importance in the pathogenesis of a broad range of immune diseases are under active investigation. However, little is currently known about the role of Th17 cells in ischemia-reperfusion (IR) injury of the kidney, a common pathophysiologic occurrence in various renal disease processes. Methods: We measured the number of infiltrated T lymphocytes and Th17 cells in C57Bl/6 mouse kidneys in sham-operated controls and following varying degrees of renal IR injury induced by renal pedicle clamping and reperfusion. The cell count results were compared to accompanying histologic damage and serum creatinine levels after 35 min and 45 min of ischemia, and following reperfusion of 48, 72, 96, and 168 hrs. Results: The number of T lymphocytes increased as ischemia time increased. However, the number of Th17 cells was not significantly affected by prolonged ischemia and reperfusion. Furthermore, the degree of histologic damage and serum creatinine levels did not correlate with the T lymphocyte and Th17 cell count numbers. Conclusion: We did not observe any evidence that Th17 cells are directly linked to renal tissue damage caused by IR injury. The role and importance of helper T cells in renal IR injury need to be evaluated further in the light of the interaction with Th1, Th2, and regulatory T cells rather than Th17 alone.