CD8 co-receptor (CD8)

The CD8 co-receptor is a dimeric type I transmembrane glycoprotein expressed on cytotoxic T lymphocytes (CD8+ T cells). It functions as a co-receptor with the T cell receptor (TCR), binding to the α3 domain of MHC class I molecules presented on target cells. This interaction enhances antigen-specific TCR signaling and contributes to T cell development, immune cell activation, and effector functions. CD8 exists as either a homodimer of CD8α or a more common heterodimer of CD8α and CD8β. Mechanistically, CD8 not only stabilizes the TCR-peptide-MHC complex but also recruits Lck kinase for signal transduction, playing essential roles in cytotoxicity, immune regulation, and as a marker for cytotoxic T cells in diagnostic and research applications. Therapeutically, CD8 and its modulation are central to cancer immunotherapy, infectious disease control, and management of immune-mediated diseases

Other names

Cluster of differentiation 8CD8α (CD8A)CD8β (CD8B)CD8 antigenCD8 molecule

Antibody-mediated modulation or depletion of CD8 T cells\nTargeted delivery via antibody-drug conjugates\nIncorporation of CD8 domains in engineered CAR-T therapies for improved antigen recognition and signaling