Human leukocyte antigen DRB1*0401–Melanoma antigen recognized by T-cells 1 complex (HLA-DRB1*0401–Melan-A complex)

The HLA-DRB1*0401–Melan-A/MART-1 complex is a molecular assembly consisting of a specific peptide derived from the Melan-A (also known as MART-1) protein presented by the Human Leukocyte Antigen (HLA) Class II molecule DRB1*0401 (Source: UniProt P43366, PubMed: 10946282). Melan-A is a melanocyte differentiation antigen highly expressed in most melanomas, making it a significant target for immunotherapy (Source: PubMed: 15184885). While many melanoma antigens are presented via MHC Class I to CD8+ T cells, this Class II complex is crucial for activating CD4+ T-helper cells, which coordinate and sustain the anti-tumor immune response (Source: PubMed: 11739550). Therapeutic strategies targeting this complex include peptide-based vaccines and TCR-engineered T-cell therapies designed to enhance the recognition of melanoma cells by the immune system. In clinical settings, the presence of this complex on tumor cells or antigen-presenting cells serves as a focal point for inducing long-lasting cellular immunity. However, challenges include the potential for autoimmune reactions against healthy melanocytes, leading to conditions like vitiligo, and the need for precise patient HLA typing (Source: PubMed: 12631302).

Other names

HLA-DR4–MART-1 complexMHC Class II–Melan-A complexHLA-DRB1*04:01–MART-1 complexMelan-A(51-73)/DR4 complexHLA-DRB1*0401–MART-1 peptide complex

The complex acts as a ligand for specific T-cell receptors (TCRs) on CD4+ T-helper cells, triggering an immune response against cells expressing the Melan-A antigen.