SARS-CoV-2 peptide–major histocompatibility complex class I complex

The SARS-CoV-2 peptide–major histocompatibility complex class I (MHC-I) complex is a molecular entity formed when intracellular peptides derived from the SARS-CoV-2 virus are loaded onto MHC-I molecules inside infected cells and presented on the cell surface. This enables recognition by CD8+ T lymphocytes, which play a critical role in adaptive immunity by killing infected cells. The structure and immunogenicity of these peptide–MHC-I complexes depend on both the viral peptide and the host MHC-I (notably, HLA-A*02:01 in humans has been most frequently studied). Viral proteins, including several encoded by SARS-CoV-2 (e.g., ORF3a, ORF6, and ORF7a), have evolved mechanisms to inhibit antigen presentation functions of MHC-I and interfere with the formation, trafficking, or surface expression of these complexes, facilitating immune evasion. The diversity and stability of SARS-CoV-2 peptide–MHC-I complexes are under active investigation for both vaccine design and monitoring antiviral T cell responses.

Other names

SARS-CoV-2 pMHC-I complexSARS-CoV-2 peptide–MHC-I complex

Drugs or biologics targeting this complex would generally modulate antigen presentation, T cell recognition, or immune evasion mechanisms.