Anti-CD8A, clone C8/468

1 mg/ml in 1X PBS, BSA free, sodium azide free. CD8 is a cell surface receptor expressed either as a heterodimer with the beta chain or as a homodimer. A majority of thymocytes and a subpopulation of mature Tcells and NK cells express CD8a. It binds to MHC class 1 and through its association with protein tyrosine kinase p56lck plays a role in Tcell development and activation of mature Tcells. For mature Tcells, CD8 and 4 are mutually exclusive, so antibody to CD8 is generally used in conjunction with antibody to CD4. CD8a antibody is a useful marker for distinguishing helper/inducer T-lymphocytes, and most peripheral Tcell lymphomas are CD4+/CD8-. Anaplastic large cell lymphoma is usually CD4+/CD8-, and in T-lymphoblastic lymphoma/leukemia, they are often co-expressed. It is also found in littoral cell angioma of the spleen. Protein function: Integral membrane glycoprotein that plays an essential role in the immune response and serves multiple functions in responses against both external and internal offenses. In T-cells, functions primarily as a coreceptor for MHC class I molecule:peptide complex. The antigens presented by class I peptides are derived from cytosolic proteins while class II derived from extracellular proteins. Interacts simultaneously with the T-cell receptor (TCR) and the MHC class I proteins presented by antigen presenting cells (APCs). In turn, recruits the Src kinase LCK to the vicinity of the TCR-CD3 complex. LCK then initiates different intracellular signaling pathways by phosphorylating various substrates ultimately leading to lymphokine production, motility, adhesion and activation of cytotoxic T- lymphocytes (CTLs). This mechanism enables CTLs to recognize and eliminate infected cells and tumor cells. In NK-cells, the presence of CD8A homodimers at the cell surface provides a survival mechanism allowing conjugation and lysis of multiple target cells. CD8A homodimer molecules also promote the survival and differentiation of activated lymphocytes into memory CD8 T-cells. [The UniProt Consortium]