Peptide-MHC class II complex (pMHC-II)

Peptide-MHC complexes are formed when short peptides (typically 12–25 amino acids for class II) bind to the peptide-binding groove of major histocompatibility complex (MHC) molecules. MHC class II molecules are primarily found on antigen-presenting cells and present peptides derived from extracellular pathogens to CD4+ T helper cells, leading to immune activation and cytokine production. The stability and specificity of peptide-MHC complexes are central to effective immune surveillance, vaccine development, and immunotherapies. Defects or dysregulation in peptide-MHC presentation are involved in various diseases, including autoimmunity, infection, and cancer

Other names

Peptide-MHC complexPeptide–MHC class II complexpMHC-II

Antigenic peptide loading induces surface presentation to CD4+ T cells (MHC II) or CD8+ T cells (MHC I), triggering adaptive immune responses