Patient-specific tumor neoantigen–HLA complex (NeoAg-HLA) (NeoAg-HLA)

Patient-specific tumor neoantigen–HLA complexes are unique molecular targets formed when mutated proteins within a tumor are processed and presented on the cell surface by Human Leukocyte Antigen (HLA) molecules (Nature Reviews Cancer, 2021). Unlike shared tumor-associated antigens, these neoantigens arise from somatic mutations unique to an individual's cancer, making them highly specific targets with minimal risk of central tolerance or auto-reactivity (Science, 2017). These complexes are recognized by the T-cell receptor (TCR) of CD8+ or CD4+ T cells, triggering a targeted immune response against the malignancy (Frontiers in Immunology, 2020). In therapeutic contexts, these complexes are targeted using personalized vaccines (mRNA or peptide-based) designed to expand the patient's endogenous neoantigen-specific T cells (Nature Reviews Drug Discovery, 2020). Additionally, engineered TCR-T cell therapies and TCR-like antibodies are being developed to directly bind these specific peptide-MHC combinations (Journal of Hematology & Oncology, 2021). The primary challenge in targeting these complexes lies in the high degree of polymorphism in HLA alleles and the heterogeneity of mutations across different patients, requiring a truly personalized manufacturing approach (Nature, 2019).

Other names

Neoepitope-HLA complexTumor-specific antigen-MHC complexPersonalized neoantigen-MHC complexpMHC complexNeoantigen-HLA complex

The mechanism of action involves the presentation of patient-specific mutated peptides by HLA molecules to T-cell receptors (TCRs). Personalized vaccines, such as mRNA-4157, deliver genetic sequences of these neoantigens to antigen-presenting cells, which then display the neoantigen-HLA complex to prime and expand endogenous CD8+ and CD4+ T cells (Nature Reviews Drug Discovery, 2020). Alternatively, adoptive cell therapies like TCR-T involve engineering T cells to express a TCR specific to a particular neoantigen-HLA complex, leading to the direct recognition and lysis of tumor cells (Frontiers in Immunology, 2020).