Human leukocyte antigen A*02:01-Melanoma antigen recognized by T cells 1 peptide complex (HLA-A*02:01/MART-1)

The HLA-A*02:01-MART-1 peptide complex is a molecular assembly formed by the Human Leukocyte Antigen (HLA) allele A*02:01 and a processed peptide fragment derived from the Melanoma Antigen Recognized by T cells 1 (MART-1), also known as Melan-A (Kawakami et al., 1994, PNAS). This complex is primarily expressed on the surface of melanocytes and melanoma cells, where it serves as a critical recognition element for the immune system by binding to specific T-cell receptors (TCRs) on CD8+ cytotoxic T lymphocytes (UniProt MLANA Q16655). In clinical oncology, this complex is a major target for cancer immunotherapies, particularly adoptive cell transfer using TCR-engineered T cells (TCR-T) and peptide-based vaccines (Morgan et al., 2006, Science). Because MART-1 is a lineage-specific differentiation antigen, it is highly expressed in the majority of melanomas, providing a broad therapeutic target for HLA-A*02:01-positive patients. However, the presence of MART-1 in healthy melanocytes in the skin, eye, and inner ear can lead to on-target, off-tumor toxicities such as vitiligo, uveitis, and hearing loss (Johnson et al., 2009, Blood). Current research focuses on enhancing the affinity of TCRs for this complex while managing systemic inflammatory responses like cytokine release syndrome.

Other names

HLA-A2/MART-1Melan-A/HLA-A2 complexHLA-A*02:01/MLANA(26-35)MART-1(27-35)/HLA-A2MART-1(26-35)/HLA-A2pMHC complex HLA-A*02:01/MART-1

The complex acts as a ligand for specific T-cell receptors (TCRs) on CD8+ T cells; drug interaction typically involves engineering T cells to express these TCRs or using vaccines to expand endogenous T cells, leading to cytotoxic lysis of the presenting cell via perforin and granzyme release.