Melanoma-associated antigen 6 peptide-HLA complex (MAGE-A6/HLA complex)

The MAGE-A6-derived peptide/MHC complex is a specific molecular target consisting of a processed peptide fragment from the Melanoma-associated antigen 6 (MAGE-A6) protein presented on the cell surface by Major Histocompatibility Complex (MHC) molecules, typically HLA-A*01 or HLA-A*02 (UniProt: P43360). MAGE-A6 belongs to the cancer-testis antigen (CTA) family, which is characterized by high expression in various malignancies—including melanoma, lung, and head and neck cancers—while remaining silent in normal adult tissues except for the immune-privileged testes (PubMed: 23913170). This restricted expression pattern makes the MAGE-A6 peptide-MHC complex an ideal target for immunotherapy, particularly for T-cell receptor (TCR) engineered T-cell therapies (PubMed: 26034044). These therapies utilize synthetic or natural TCRs designed to recognize the specific peptide-MHC configuration with high affinity, leading to targeted destruction of tumor cells. Clinical development has often focused on MAGE-A6 in conjunction with MAGE-A3 due to their high sequence homology and shared epitopes, such as the EVDPIGHLY peptide presented by HLA-A*01 (PubMed: 21325538). However, careful screening is required to avoid off-target reactivity against similar peptides in vital organs, as seen in historical trials where cross-reactivity with MAGE-A12 or Titin caused severe adverse events (PubMed: 23733882).

Other names

MAGE-A6 peptide-MHC complexMAGEA6-HLA complexCancer/testis antigen 1.6 peptide-MHCMAGE-A6-derived peptide/MHC complex

The target acts as a ligand for specific T-cell receptors (TCRs) on cytotoxic T lymphocytes. Upon binding, the TCR triggers a signaling cascade that leads to the activation of the T-cell and subsequent lysis of the tumor cell presenting the peptide-MHC complex (PubMed: 26034044).