Description: The RMT3-23 monoclonal antibody reacts with mouse Tim-3, a Th1-specific cell surface protein. The RMT3-23 antibody reacts with Tim-3 protein expressed by both BALB/c and C57BL/6 strains of mice. Tim-3, a type I transmembrane protein, contains an immunoglobulin and a mucin-like domain in its extracellular portion and a tyrosine phosphorylation motif in its cytoplasmic portion. Tim-3 is expressed selectively by differentiated CD4+Th1 and CD8+Tc1 cells, but is absent on CD4+Th2 and CD8+Tc2 cells. Other hematopoietic cell types, including naïve T cells, B cells, macrophages and dendritic cells, do not express Tim-3, at least at the protein level. Tim-3 expression is upregulated at a late stage of T cell differentiation on Th1 cells after 3 rounds of in vitro polarization suggesting a role for this molecule in the transport or effector function of Th1 cells rather than a contribution to T cell differentiation. In an experimental autoimmune encephalomyelitis (EAE) model, Tim-3 was shown to be expressed on most CD4+ and CD8+ T cells in the central nervous system at the onset of clinical signs of disease, while less than 2% of CD4+ cells in the periphery expressed Tim-3 after immunization.
RMT3-23 has been shown to have functional activity; blocks DC recognition of apoptotic cells and also induces autoantibody production.
