Tumor-specific peptide-HLA complex

A **tumor-specific peptide-HLA complex** is a molecular entity formed by the binding of a tumor-derived peptide, frequently a neoantigen (mutation-derived peptide), to a human leukocyte antigen (HLA) molecule—typically, but not exclusively, class I HLA (MHC-I) on the surface of a tumor cell. These complexes are presented on the tumor cell membrane, where they can be recognized by cytotoxic T lymphocytes (CTLs) via their T-cell receptors (TCRs). The specificity of the peptide and the HLA allele determines immune recognition, immune surveillance, and the potential for targeted immunotherapies. Therapeutic strategies—including engineered T cells and TCR-mimic antibodies—can selectively recognize these complexes and kill tumor cells presenting them. However, cross-reactivity with self-peptides, HLA restriction, and downregulation of HLA in tumors present significant translational challenges. These complexes serve both as therapeutic targets and as biomarkers for patient selection in various cancer immunotherapy settings [1][2][3][4][5][6][7].

Other names

Tumor-associated peptide-HLA complexCancer neoantigen-HLA complexTumor antigen-MHC complexpHLA complex (when referring to peptide-HLA complex)Tumor epitope-MHC complex

Direct recognition of pHLA complexes on tumor cells by engineered TCR or antibodies, leading to targeted cell killing [1][3][5] Stimulation of T cell immunity specific to tumor-derived peptides [2][3] Blockade of tumor immune escape via recognition and response to pHLA complexes [3]