Patient-specific tumor peptide-major histocompatibility complex (pMHC)

Patient-specific tumor peptide–major histocompatibility complex (pMHC) molecules are unique cell-surface structures composed of a neoantigenic peptide bound to a major histocompatibility complex (MHC) molecule. These complexes are formed when somatic mutations in a patient's tumor produce novel proteins that are processed and presented to the immune system, acting as primary signals for T-cell recognition (Source: NIH, PubMed). Because neoantigens arise from mutations unique to an individual's cancer, these pMHCs represent highly specific targets that minimize the risk of damage to healthy tissues (Source: Nature Reviews Cancer). Therapeutic strategies targeting these complexes include personalized neoantigen vaccines, such as mRNA-4157, and adoptive cell therapies using engineered T-cell receptors (TCR-T) (Source: Journal of Clinical Oncology). By binding specifically to the peptide-groove of the MHC, these therapies trigger a potent and selective cytotoxic immune response against solid tumors (Source: Science). However, the clinical efficacy of targeting pMHCs can be challenged by the tumor's ability to downregulate MHC expression or the presence of high intratumoral heterogeneity (Source: Cell). Despite these challenges, pMHCs remain a cornerstone of precision oncology and personalized immunotherapy development.

Other names

Neoantigen-MHC complexTumor-specific antigen-MHC complexNeoepitope-HLA complexTSA-HLA complexPersonalized tumor-associated antigen-MHC

Recognition of the specific peptide-MHC complex by T-cell receptors (TCRs) or TCR-mimetic molecules, leading to the activation of cytotoxic T-lymphocytes and subsequent lysis of the tumor cell.