Neoantigen-Major Histocompatibility Complex-T-cell receptor complex (NeoAg-MHC-TCR) (NeoAg-MHC-TCR)

The Neoantigen-Major Histocompatibility Complex-T-cell receptor (NeoAg-MHC-TCR) complex is the fundamental structural unit recognized by the adaptive immune system to distinguish malignant cells from healthy tissue. Neoantigens are unique peptides derived from somatic mutations specific to an individual's tumor, which are processed and presented on the cell surface by Major Histocompatibility Complex (MHC) molecules, also known as Human Leukocyte Antigens (HLA). The interaction between this peptide-MHC complex and a specific T-cell receptor (TCR) is the critical step in initiating a targeted immune response against cancer. This complex is the primary target for personalized immunotherapy strategies, including neoantigen-based vaccines that prime endogenous T cells and adoptive TCR-T cell therapies that utilize engineered T cells to recognize these specific markers (Blass & Ott, 2021, Nature Reviews Clinical Oncology). Because neoantigens are not expressed in normal tissues, targeting this complex minimizes the risk of autoimmune-like toxicities compared to shared tumor-associated antigens. However, the high degree of patient specificity requires complex, individualized manufacturing processes for both vaccines and cell therapies. Success in targeting this complex depends on the accurate identification of immunogenic neoepitopes through genomic sequencing and the maintenance of MHC expression by the tumor to prevent immune escape. Current clinical research focuses on optimizing neoantigen prediction algorithms and overcoming the immunosuppressive tumor microenvironment to enhance the durability of the TCR-mediated response (Yarchoan et al., 2017, JCI Insight).

Other names

Patient-specific tumor-associated antigen-MHC-TCR complexNeoepitope-HLA-TCR complexTumor-specific antigen-MHC-TCR complexpMHC-TCR complexMutated peptide-MHC-TCR complex

The mechanism of action involves the high-affinity binding of a T-cell receptor (either endogenous or engineered) to a specific neoantigen peptide presented by a Major Histocompatibility Complex (MHC) molecule on the surface of a tumor cell. This interaction induces a signaling cascade through the CD3 complex, leading to T-cell activation, cytokine production (e.g., IFN-gamma), and the release of cytotoxic granules (perforin and granzymes) that mediate targeted apoptosis of the tumor cell (Schumacher & Schreiber, 2015, Science; Rosenberg & Restifo, 2015, Science).