Rabbit Polyclonal antibody to CD365

T cell Ig~ and mucin~domain~containing molecules (TIMs) are a family of transmembrane proteins expressed by various immune cells. TIM~1 (HAVCR1 (hepatitis A virus cellular receptor 1), KIM~1 (kidney injury molecule~1) was originally identified as a receptor for hepatitis A virus. TIM~1 also acts as a costimulatory receptor on T cells and following activation, associates with the TCR complex to upregulate signaling and cytokine production. Another TIM family member, TIM~4, is expressed by antigen presenting cells and is a ligand for TIM~1. TIM~1 expressed by Th1 and Th17 cells was also recently shown to interact with P~selectin to mediate T cell trafficking during inflammation and autoimmune disease. NKT cells also express TIM~1, and engagement of TIM~1 on NKT cells leads to increased production of IL~4, but decreased production of IFN~gamma. TIM~1 is also a receptor for phosphatidylserine exposed by cells undergoing apoptosis. Detection of phosphatidylserine by TIM~1 expressed on NKT cells results in activation, proliferation, and cytokine production. Expression of TIM~1 on regulatory B cells is required for optimal production of IL~10. Mice lacking the TIM~1 mucin domain have decreased production of IL~10 by regulatory B cells, hyperactive T cells, increased levels of inflammatory cytokines, and enhanced severity of autoimmune disease. In addition, TIM~1 polymorphisms are associated with susceptibility to atopic diseases including asthma. Finally, expression of TIM~1 is increased in renal tubular epithelial cells following kidney injury.