CD8B

CD8B is a gene that encodes a protein component of the CD8 molecule, a cell surface glycoprotein found on cytotoxic T lymphocytes and some natural killer cells. The CD8 molecule is a heterodimer composed of either alpha and beta chains (CD8αβ) or two alpha chains (CD8αα). The CD8B gene specifically codes for the CD8 beta chain, which is one of the two subunits that form the CD8αβ heterodimer. This heterodimer plays a crucial role in the adaptive immune system by acting as a co-receptor for the T cell receptor (TCR).

The CD8 beta chain, along with the CD8 alpha chain, binds to the MHC class I molecule on antigen-presenting cells. This interaction stabilizes the binding of the TCR to the peptide-MHC complex, thereby enhancing T cell activation. CD8+ T cells, characterized by their expression of CD8, are primarily responsible for identifying and eliminating cells infected with viruses or other intracellular pathogens, as well as cancerous cells. The CD8 beta chain contributes significantly to the overall structure and function of the CD8 co-receptor complex, mediating critical signaling pathways necessary for T cell effector functions. Mutations or altered expression of CD8B can have implications for immune system regulation and disease susceptibility.