Figure 1.

The tripartite T-cell receptor–peptide–MHC class I complex (TCR–pMHCI)–CD8 interaction. A representation of the tripartite TCR–pMHCI–CD8 interaction that forms part of the polyvalent interface between a CD8⁺ cytotoxic T lymphocyte and a target cell during the process of antigen recognition. This interaction governs T-cell activation and triggers target cell killing through the release of cytotoxic granules and lymphokines, and through the induction of apoptotic signals.