Patient-specific tumor neoantigen-MHC class I complex (pMHC I)

Patient-specific tumor neoantigen-derived peptides presented on MHC class I molecules are highly specific markers of malignancy that arise from unique somatic mutations within a patient's tumor (Frontiers in Immunology, 2024). These mutations, which include single nucleotide variants, insertions, and deletions, result in novel protein sequences that are processed and displayed on the cell surface by Major Histocompatibility Complex (MHC) class I proteins (Frontline Genomics, 2020). Because these neoantigens are not expressed in healthy tissues, they are not subject to central tolerance, making them ideal targets for inducing potent, tumor-specific CD8+ T-cell responses (NIH, 2024). Therapeutic approaches targeting these complexes include personalized cancer vaccines—such as mRNA, DNA, or peptide-based platforms—and adoptive cell therapies using T cells engineered with neoantigen-specific T-cell receptors (TCRs) (AACR Journals, 2023). These treatments aim to overcome the immunosuppressive tumor microenvironment by priming the immune system to recognize and eliminate cells harboring these specific genetic alterations (Frontiers in Oncology, 2021). Personalized vaccines like Autogene cevumeran and mRNA-4157 deliver genetic sequences of these neoantigens to stimulate de novo immune responses (DrugFuture, 2021). However, the clinical success of targeting these complexes depends on the accurate prediction of immunogenic epitopes and the prevention of immune escape mechanisms like HLA loss of heterozygosity (BMJ, 2021). Despite logistical challenges in manufacturing, these targets represent a transformative shift toward precision oncology (ResearchGate, 2026).

Other names

Neoantigen-MHC class I complexTumor-specific antigen-MHC complexPersonalized neoantigen-MHC complexpMHC I complexMutant peptide-MHC class I complex

Personalized vaccines (mRNA, DNA, or peptide) deliver sequences encoding tumor-specific neoantigens to antigen-presenting cells, which then process and present these peptides on MHC class I molecules to prime and expand neoantigen-specific CD8+ T cells (Frontiers in Immunology, 2024). Alternatively, TCR-T cell therapies involve engineering a patient's T cells to express receptors that directly recognize and bind to these specific neoantigen-MHC complexes on the surface of tumor cells, leading to targeted cell lysis (AACR Journals, 2023).