Melanoma antigen recognized by T cells 1-specific T-cell receptor (MART-1 TCR) (MART-1 TCR)

The Melanoma antigen recognized by T cells 1-specific T-cell receptor (MART-1 TCR) is a specialized heterodimeric protein complex engineered or selected to recognize the MART-1 (Melan-A) differentiation antigen (Morgan et al., 2006, Science). MART-1 is highly expressed in most melanoma tumors but is otherwise restricted to normal melanocytes in the skin, eyes, and inner ear (Johnson et al., 2009, Blood). This TCR specifically binds to MART-1 peptide fragments, most commonly the AAGIGILTV decamer, when presented by the Human Leukocyte Antigen (HLA)-A*02:01 molecule. Upon binding, the TCR initiates a signaling cascade in CD8+ T lymphocytes that leads to the secretion of pro-inflammatory cytokines and the release of cytotoxic granules, resulting in the targeted destruction of melanoma cells (Chodon et al., 2014, Clinical Cancer Research). In clinical practice, patient T cells are genetically modified to express high-affinity versions of this TCR, such as the F5 or DMF5 clones, to treat metastatic melanoma. However, the presence of MART-1 in healthy melanocytes can lead to "on-target, off-tumor" toxicities, manifesting as vitiligo, uveitis, and sensorineural hearing loss (Morgan et al., 2006, Science).

Other names

Melan-A-specific T-cell receptorMART-1/Melan-A TCRF5 T-cell receptorDMF5 T-cell receptorMART-1-specific T-cell receptor on CD8+ T lymphocytes

The TCR recognizes the MART-1 peptide (e.g., AAGIGILTV) presented by HLA-A*02:01 on melanoma cells, triggering T-cell activation and the release of cytotoxic molecules like granzymes and perforins to induce apoptosis in the target cell (Morgan et al., 2006, Science; Johnson et al., 2009, Blood).