Anti-Mouse H-2Kb (MHC Class I) [Y-3] In Vivo Antibody - Low Endotoxin (IVMB0009)

H-2K antibody, clone Y-3, recognizes the major histocompatibility complex (MHC) class I H-2K haplotypes b, k, q, r, s, but not d. MHC class I is ubiquitously expressed on the cell surface of nucleated cells and consists of a 45-kDa type I transmembrane glycoprotein (α-chain or heavy chain) and a 12-kDa soluble protein (β2-microglobulin, β2M). The α-chain consists of three domains (α1, α2, and α3)3. α1 and α2 form the closed antigen-binding groove and bind to 8-10 aa peptides derived from cytosolic antigens. β2M noncovalently associates with α3, which is essential for MHC stability. H-2K plays a critical role in the adaptive immune response by presenting endogenous antigens to cytotoxic CD8 T cells. MHC class I molecules can also present exogenous antigens to CD8 T cells via a process known as cross-presentation. The T cell receptor (TCR)/CD3 complex of CD8 T cells interacts with peptide-MHC class I, which induces CD8 T cell activation and subsequent cell-killing. CD8 molecules also bind to MHC class I, which helps augment TCR signaling. In contrast to CD8 T cells, MHC class I is an inhibitory ligand for natural killer (NK) cells, promoting self tolerance. MHC class I also contributes to the positive selection of CD8 T cells and NK cell specificity.