Tumor-specific peptide–Major Histocompatibility Complex (pMHC)

Tumor-specific peptide–Major Histocompatibility Complex (pMHC) molecules represent a class of highly specific therapeutic targets in oncology, particularly for personalized immunotherapy. These complexes are formed when neoantigens—peptides derived from somatic mutations identified through sequencing a patient's tumor mRNA and DNA—are processed and presented on the cell surface by MHC (or HLA in humans) molecules [Sahin et al., 2017, Nature]. Because these neoantigens arise from non-synonymous mutations unique to the tumor, they are absent from the normal proteome, minimizing the risk of central tolerance and off-target toxicity [Blass & Ott, 2021, Nat Rev Clin Oncol]. Therapeutic strategies targeting these pMHCs include personalized mRNA vaccines, which encode the predicted neoepitopes to prime the patient's immune system, and adoptive cell therapies using T-cell receptors (TCRs) engineered to recognize specific pMHC signatures [Ott et al., 2017, Nature]. The successful recognition of these complexes by CD8+ cytotoxic T cells triggers a cascade of immune-mediated cell death, making them a cornerstone of precision oncology [Finn, 2018, N Engl J Med]. The efficacy of targeting pMHCs is heavily dependent on the patient's HLA type and the stability of the peptide-MHC interaction [Hu et al., 2021, Science].

Other names

Neoantigen-MHC complexTumor-specific antigen-MHC complexNeoepitope-HLA complexPersonalized neoantigenTSA-MHC complex

Induction of tumor-specific T-cell responses through the presentation of unique mutation-derived peptides on MHC molecules, leading to selective recognition and lysis of cancer cells by CD8+ and CD4+ T lymphocytes.