Major histocompatibility complex–neoantigen complex and T-cell receptor (MHC–neoantigen–TCR complex)

The major histocompatibility complex–neoantigen complex and T-cell receptor refers to the three-part molecular assembly comprising a major histocompatibility complex (MHC) molecule presenting a disease-specific peptide (neoantigen), recognized by a specific T-cell receptor (TCR) on the surface of a T lymphocyte. This interaction is the principal gateway for adaptive immune recognition of tumors, infections, and other disease states. Structural studies show highly variable yet specific contacts, typically involving the TCR’s complementarity-determining regions (CDRs) engaging both the peptide and MHC helices, resulting in highly individualized immune responses. The clinical relevance is profound: therapies targeting this complex, including engineered T cells, vaccines, and monoclonal antibodies, seek to precisely direct or modulate the immune response against disease. Precision and safety hinge on accurate identification of disease-relevant peptide–MHC targets and matching TCR recognition patterns. The molecular complexity—and the specificity of the peptide epitope, MHC allele, and TCR—mean therapeutic strategies must account for polymorphism and the potential for cross-reactivity, thereby informing patient selection, efficacy monitoring, and risk assessment in clinical immunotherapy.

Other names

Peptide–MHC complex and T-cell receptorpMHC–TCR complexTCR–pMHC complexT-cell antigen receptor complex (structural context)T-cell receptor–major histocompatibility complex–peptide complex

Blockade or modulation of the TCR–pMHC interaction (preventing T-cell activation or promoting activation); Enhancement of T-cell response to tumor antigens; Redirection of T-cell specificity using engineered receptors (CAR–T, TCR–T cells); Inhibition of off-target/cross-reactivity by designing high specificity candidates