CD8 alpha Protein, Rat (HEK293, Fc)

The CD8 alpha protein, an integral membrane glycoprotein, plays a pivotal role in the immune response, serving multiple functions in responses against both external and internal threats. In T-cells, it functions primarily as a coreceptor for the MHC class I molecule:peptide complex, interacting simultaneously with the T-cell receptor (TCR) and the MHC class I proteins presented by antigen-presenting cells (APCs). This interaction facilitates the recruitment of the Src kinase LCK to the vicinity of the TCR-CD3 complex. LCK, in turn, initiates various intracellular signaling pathways by phosphorylating diverse substrates, ultimately leading to lymphokine production, motility, adhesion, and the 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 the conjugation and lysis of multiple target cells. CD8A homodimer molecules also contribute to the survival and differentiation of activated lymphocytes into memory CD8 T-cells. CD8 alpha forms disulfide-linked heterodimers with CD8B at the cell surface and also homodimers in various cell types, including NK-cells and peripheral blood T-lymphocytes. Additionally, it interacts with the MHC class I HLA-A/B2M dimer and associates with LCK in a zinc-dependent manner.