TIM3,also known as HAVCR2,is a member of the recently discovered T cell Ig and mucin domain-containing molecule superfamily. TIM3 is a negative regulatory molecule that is important for T cell tolerance and has a crucial role in autoimmunity and T cell exhaustion during chronic viral infection . TIM3 is expressed by T-helper type 1 (Th1) cells,macrophage,monocyte,dendritic cells,CD8+ T cell and other lymphocyte subsets. Galectin-9 is a ligand for TIM3. TIM3-galectin-9 pathway negatively regulates T helper type 1 immunity . TIM3 is a 280-aa membrane protein with a calculated molecular weight of 33 kDa,the higher molecular weights between 50 and 70 kDa detected by this monoclonal antibody probably represent glycosylated TIM3 .