Tim-3 promoted renal ischemia/reperfusion injury through regulating mononuclear phagocyte system function / 中华器官移植杂志

ABSTRACT

Objective To investigate the effects of Tim-3 on the renal ischemia-reperfusion injury (IRI),and explore the role of monocyte-macrophage cell system.Methods Totally 72 C57BL/ 6 mice were randomly divided into four groups (n =18 each).(1) IR + Tim-3 rnAb group (experimental group):Each mouse was intraperitoneally injected with 200μg of anti-Tim-3 mAb and the IR model of mouse kidney was established after 1 day;(2) IR + IgG monoclonal antibody group (negative control group):each mouse was intraperitoneally injected with anti-IgG mAb (200 μg) and the IR model of mouse kidney was established after 1 day;(3) IR group:mouse kidney IR model was established only;(4) Control group:mouse kidney IR model was not established.At 6,24 and 48 h after IR respectively,venous blood of 6 mice in each group was taken from the infrarenal vein.Scr and CystinC were detected and PAS staining was used to observe the pathological change of renal tissues.Cell apoptosis was detected by TUNEL staining.Pax,bcl-2 and caspase-3 expression in renal tissue was detected by Western blotting.Immunohistochemistry was used to detect the distribution of Tim-3 and activated macrophage cells.Flow cytometry and ELISA were used to evaluate the level of Tim-3 and inflammatory cytokines secretion respectively.Results Compared with control group,the Tim-3 expression was dramatically increased in IR group and I/R + Tim-3 mAb group.The serum Scr and CystinC levels were increased in IR group,and Tim-3 blocking decreased the levels of serum Scr and CystinC (P＜0.05).PAS and TUNEL staining showed that renal injury score and apoptotic index were higher in IR group than those in control group.Tim-3mAb significantly decreased those markers,and ameliorated the renal tubulointerstitial injury induced by IRk The expression levels of Caspase-3 and Bax/bcl-2 was increased in IR group,but deceased by Tim-3mAb.IR induced F4/80 + distribution and inflammatory cytokines secretion in renal tubular interstitial tissues,while Tim-3mAb down-regulated F4/80 + activation and the levels of inflammatory cytokines.Conclusion The findings demonstrated Tim-3 may promoted renal IRI through regulating mononuclear phagocyte system function.