The 53-6.7 antibody reacts with murine CD8a, a 32 – 34 kDa type I transmembrane glycoprotein which is a subunit of CD8. CD8 is a disulfide-bonded dimer, found either as a heterodimer of CD8a (α) and CD8b (β) subunits (i.e., αβ) or a homodimer (αα). CD8 acts as a co-receptor to the T cell receptor (TCR) during T cell activation by binding MHC Class I molecules presented by an antigen-presenting cell. It functions to strengthen the association between the TCR and MHC I-antigen complex and to amplify signals from the TCR to the cytoplasm through the interaction of its intracellular domain with cytoplasmic tyrosine kinases such as Lck. The CD8a chain binds to the alpha-3 domain of class I MHC molecules. CD8 is expressed in the αβ form by a majority of thymocytes and a subset of mature peripheral blood T cells (T cytotoxic cells), and in the ββ form by γδ T cells, a subset of intestinal intraepithelial lymphocytes and dendritic cells. The 53-6.7 antibody reportedly blocks antigen presentation via MHC class I and inhibits IL-2-dependent T cell responses.

This antibody clone has been verified for purity assessments of cells isolated with EasySep™ kits, including EasySep™ Mouse CD8+ T Cell Isolation Kit  and EasySep™ Mouse CD90.2 Positive Selection Kit II