Major histocompatibility complex class I viral peptide complex (MHC-I viral peptide complex)

The major histocompatibility complex class I viral peptide complex is a molecular assembly displayed on the surface of virus-infected host cells. It consists of an MHC Class I molecule (such as HLA-A, HLA-B, or HLA-C in humans) bound to a short (usually 8–10 amino acid) peptide derived from viral proteins, processed by intracellular proteases. The complex enables cytotoxic T lymphocytes to specifically recognize and kill infected cells by binding to the complex via their T cell receptors. Crystal and molecular models reveal the peptide sits in a groove formed by the MHC molecule, with high polymorphism in both MHC molecules and peptide sequences contributing to immune specificity and diversity. This target is central to antiviral immunity and forms the basis for many immunotherapeutic strategies and immune monitoring assays.

Other names

Peptide–MHC complexPeptide–HLA complex (for human MHC)Antigen–MHC complexViral peptide–MHC-I complexpMHC (abbreviation for peptide–MHC complex)

Recognition and binding by T cell receptor (TCR), leading to T cell activation and cytotoxic effects; Induction of apoptosis in infected host cells