Melanoma antigen recognized by T cells 1 (MART-1) peptide–HLA-A*0201 complex (MART-1/HLA-A*0201 complex)

The MART-1/Melan-A peptide–HLA-A*0201 complex is a major histocompatibility complex (MHC) class I-restricted antigen that serves as a critical target for immunotherapy in melanoma [3, 6]. It consists of a peptide fragment derived from the Melanoma Antigen Recognized by T cells 1 (MART-1), also known as Melan-A, which is presented on the cell surface by the HLA-A*0201 allele [17, 18]. This complex is highly expressed in over 80-90% of melanomas, making it one of the most extensively studied tumor-associated antigens [12, 33]. Therapeutic approaches targeting this complex include T-cell receptor (TCR)-engineered T-cell therapies (such as DMF5 and 1D3HMCys) and peptide-based vaccines designed to elicit a robust cytotoxic T-lymphocyte response [20, 23, 28]. A significant challenge in targeting this complex is "on-target, off-tumor" toxicity, as MART-1 is also expressed in normal melanocytes found in the skin, eyes, and ears [1, 7]. Clinical trials have reported adverse events such as severe dermatitis, uveitis, and hearing impairment resulting from the immune system's attack on these healthy tissues [2, 9, 36]. Despite these safety concerns, the MART-1/HLA-A*0201 complex remains a foundational model for developing TCR-based therapies and understanding the mechanisms of T-cell cross-reactivity and tumor escape [26, 38].

Other names

Melan-A/HLA-A*0201 complexMART-1(26-35)/HLA-A*0201 complexMART-1(27-35)/HLA-A*0201 complexMLANA/HLA-A*0201 complexMART-1/HLA-A2 complexMelan-A/HLA-A2 complex

TCR-T cell therapy involves engineering autologous T cells to express a specific T-cell receptor (TCR) that recognizes the MART-1 peptide presented by HLA-A*0201, leading to targeted tumor cell lysis. Peptide vaccines aim to induce an endogenous cytotoxic T-lymphocyte (CTL) response against the MART-1/HLA-A*0201 complex on melanoma cells.