Tumor-specific neoantigen-HLA class I complex (NeoAg-HLA-I)

A tumor-specific neoantigen-HLA class I complex consists of a mutated peptide fragment, derived from a patient's unique tumor mutations, bound to a Human Leukocyte Antigen (HLA) class I molecule on the cell surface. These neoantigens arise from non-synonymous somatic mutations, such as single nucleotide variants or frameshifts, and are absent from healthy tissues, providing a high degree of tumor specificity (Schumacher & Schreiber, 2015, Nature). The primary biological function of this complex is to present 'non-self' signals to the immune system, specifically to the T-cell receptors (TCRs) of CD8+ cytotoxic T lymphocytes (CTLs). Upon recognition, the CTLs are activated to destroy the presenting tumor cell, making these complexes ideal targets for personalized immunotherapy (Sahin & Türeci, 2018, Science). Current therapeutic approaches include personalized cancer vaccines, such as mRNA-4157 and Autogene cevumeran, which prime the immune system to recognize these specific complexes (Weber et al., 2024, The Lancet). Additionally, adoptive cell therapies using TCR-engineered T cells are being developed to target common driver mutations like KRAS G12D presented by specific HLA alleles (Leidner et al., 2022, NEJM). Despite their potential, challenges include the high heterogeneity of mutations between patients and the ability of tumors to evade detection by downregulating HLA expression.

Other names

Neoepitope-HLA complexMutated neoantigen-MHC class I complexPatient-specific neoantigenTumor-specific antigen (TSA)Neoantigen-HLA-A/B/C complex

Induction of a targeted cytotoxic T-cell response where T-cell receptors (TCRs) specifically recognize and bind the mutated peptide-HLA complex, triggering granzyme and perforin-mediated lysis of the tumor cell.