Anti-CD8A, clone CD8/4391R

1 mg/ml in 1X PBS, BSA free, sodium azide free. The CD8 antigen is a cell surface glycoprotein found on most cytotoxic T lymphocytes that serves as a coreceptor for TCR recognition of MHC class I associated peptides and supports CTL activation by binding to the MHC, while making no direct contact with the peptide.CD8 is expressed on cytotoxic suppressor T cells. It is expressed as a heterodimer of CD8 occasionally positive cells were also identified within germinal centers and within the investing squamous epithelium. In other tissues, only lymphoid cells and cells of histiocyte lineage showed positive staining for CD8. 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]