ABSTRACT
T cell immunoglobulin and mucin domain 3 (Tim-3) is well known to negatively regulate T cells responses,but its role in burn-induced T cells immune suppression remains unclear.In the present study,in order to identify the relationship between Tim-3 expression and post-bum T cells immune suppression,C57BL/6 mice were subjected to bum injury or sham injury,and the liver and spleen were harvested at the day 1 after operation.The expression level of Tim-3 on hepatic or splenic T cells and the functional properties of Tim-3+ T cells were evaluated.It was found burn injury induced dramatically elevated Tim-3 expression on both hepatic and splenic CD4+ and CD8+ T cells in contrast with the post-burn depletion of T cells.Furthermore,Tim-3 expression was correlated with the suppressive phenotype of T cells following burn injury,including increased expression of anti-inflammatory cytokine IL-10,decreased expression of pro-inflammatory cytokines IFN-γ and TNF-α,reduced T cell proliferation and elevated co-expression of Tim-3 and PD-1.Moreover,Tim-3+ T cells subsets were more prone to spontaneous apoptosis than Tim-3 T cells subsets.Our findings reinforce the idea that the up-regulated expression of Tim-3 on T cells after bum injury plays an important role in the development and maintenance of burn-induced T cell immune suppression.