Patient-specific tumor-associated peptide-Major Histocompatibility Complex (pMHC)

Patient-specific tumor-associated peptide-Major Histocompatibility Complex (pMHC) refers to the unique combination of a neoantigenic peptide and a patient's own HLA molecule presented on the surface of malignant cells [1]. These complexes arise from somatic mutations—such as non-synonymous single nucleotide variants, insertions, or deletions—that are unique to an individual's tumor and are not found in healthy tissue [2]. Because these neoantigens are perceived as "non-self" by the immune system, they are primary targets for personalized immunotherapy, including neoantigen vaccines and TCR-engineered T-cell therapies [3]. The therapeutic goal is to induce or enhance a T-cell mediated attack specifically against cells displaying these pMHC signatures, thereby minimizing damage to normal cells [4]. However, the effectiveness of targeting these complexes can be hindered by tumor heterogeneity, where only a subset of cells expresses the target, or by the tumor's ability to downregulate MHC expression to evade detection [1, 2]. Monitoring these targets often involves genomic sequencing and bioinformatic prediction of peptide-MHC binding affinity to identify the most immunogenic candidates for therapy [2].

Other names

Neoantigen-MHC complexTumor-specific antigen-MHC complexTSA-HLA complexNeoepitope-HLA complexPatient-specific pMHC

Targeting these complexes involves the use of vaccines or engineered T-cells to facilitate T-cell receptor (TCR) recognition of the specific peptide-MHC combination, triggering a targeted cytotoxic immune response against tumor cells [1, 2, 3].