CD8

CD8 is a cell surface glycoprotein found on most cytotoxic T lymphocytes that mediates efficient cell-cell interactions within the immune system. CD8 acts as a co-receptor, and the T-cell receptor on the T lymphocyte recognize antigen displayed by an antigen presenting cell (APC) in the context of class I MHC molecules. The functional CD8 consists of two alpha chains, or a heterodimer composed of one alpha and one beta chain. Alpha and beta chains have a strong homology to immunoglobulins with variable light channels. CD8 identifies cytotoxic/suppressor t-cells that interact with MHC class I bearing targets. CD8 is thought to play a role in the process of t-cell mediated killing. The alpha chains of CD8 bind to the alpha domains of classI MHC molecules, alpha 3.

Cluster of differentiation 8

CD8