HLA-A*0201-presented MART-1 peptide (HLA-A2/MART-1)

The HLA-A*0201-presented MART-1 peptide is a specific peptide-major histocompatibility complex (pMHC) found on the surface of cells, particularly melanoma cells and professional antigen-presenting cells like dendritic cells. MART-1 (Melanoma Antigen Recognized by T cells 1), also known as Melan-A, is a lineage-specific differentiation antigen highly expressed in melanocytes and the majority of melanoma cases (Citations: UniProt Q16655; PubMed: 8164633). In the context of immunotherapy, the MART-1 peptide—often the modified ELAGIGILTV sequence which exhibits higher affinity than the native AAGIGILTV sequence—is loaded onto HLA-A*0201 molecules to prime and expand cytotoxic CD8+ T cells. This complex serves as a critical target for various immunotherapeutic strategies, including peptide vaccines, dendritic cell vaccines, and T-cell receptor (TCR) engineered T-cell therapies (Citations: PubMed: 16946075). By targeting this complex, the immune system is directed to recognize and destroy melanoma cells that express the MART-1 protein. However, because MART-1 is also expressed in normal melanocytes in the skin, eye, and ear, therapeutic interventions can lead to autoimmune-like side effects such as vitiligo, uveitis, or hearing loss (Citations: PubMed: 19451549).

Other names

Melan-A peptideMART-1(26-35) peptideHLA-A*02:01/Melan-A complexMART-1/HLA-A2 complexAntigen isolated from immunotherapeutic melanoma vaccine

The complex acts as a ligand for specific T-cell receptors (TCRs) on CD8+ cytotoxic T lymphocytes. When presented on dendritic cells, it facilitates the priming and expansion of MART-1-specific T cells; when presented on tumor cells, it serves as the recognition site for these T cells to execute cell lysis (Citations: UniProt Q16655; PubMed: 19451549).