CD8, also known as T8 and Leu2, is a type I membrane glycoprotein. CD8, is a member of the immunoglobulin superfamily found on the majority of thymocytes, a subset of peripheral blood T cells, and NK cells (which express almost exclusively CD8a homodimers). CD8 acts as a co-receptor with MHC class I-restricted T cell receptors in antigen recognition and T cell activation and has been shown to play a role in thymic differentiation. Two domains in CD8a are important for function: the extracellular IgSF domain binds the α3 domain of MHC class I, and the cytoplasmic CXCP motif binds the tyrosine kinase p56 Lck.
Anti-Mouse CD8a (53-6.7)-168Er—100 Tests