Patient-specific tumor neoantigen–MHC class I complex (NeoAg-MHC-I complex)

Patient-specific tumor neoantigen–MHC class I complexes are unique molecular structures formed when mutated proteins within a cancer cell are processed and presented on the cell surface by Major Histocompatibility Complex (MHC) class I molecules (Nature Reviews Cancer, 2021). These neoantigens arise from somatic mutations, such as single nucleotide variants or frameshifts, and are absent in healthy tissues, making them ideal targets for highly specific immunotherapy (Science, 2017). The primary biological function of these complexes is to serve as recognition signals for the immune system, specifically for the T-cell receptors (TCRs) of CD8+ cytotoxic T lymphocytes (NEJM, 2019). In oncology, these complexes are the foundation for personalized cancer vaccines and adoptive cell therapies, which aim to prime or engineer the immune system to selectively destroy tumor cells while sparing normal ones (Nature, 2017). Therapeutic strategies include mRNA-based vaccines, such as mRNA-4157, and TCR-engineered T cells designed to bind these specific MHC-peptide combinations (Cell, 2020). These therapies work by presenting non-self peptides to the immune system, thereby overcoming the central tolerance that often limits traditional tumor-associated antigen targets. However, challenges such as tumor heterogeneity, HLA downregulation, and the risk of antigen escape remain significant hurdles in effectively targeting these complexes (Cancer Discovery, 2019). Additionally, the high degree of polymorphism in HLA molecules requires sophisticated computational algorithms to predict which neoantigens will successfully bind and be presented (Nature Biotechnology, 2020).

Other names

Tumor-specific antigen-MHC complexNeoepitope-HLA complexTSA-MHC complexNeoantigen-HLA-I complexPersonalized neoepitope-MHC complex

Presentation of tumor-specific mutated peptides to CD8+ T cells, facilitating T-cell receptor (TCR) recognition and subsequent cytotoxic immune response against tumor cells.