Tumor-associated and melanoma-associated peptide antigens presented on patient-specific human leukocyte antigen (HLA) (TAA/MAA-HLA complex)

Tumor-associated and melanoma-associated peptide antigens presented on patient-specific human leukocyte antigen (HLA) molecules are critical targets for modern cancer immunotherapy. These targets consist of short peptide fragments derived from intracellular proteins—such as mutated neoantigens or overexpressed lineage proteins like gp100 and MART-1—that are displayed on the cell surface by HLA molecules for recognition by T-cells (PubMed: 26667334). In melanoma, the high mutational burden often results in a diverse array of neoantigens that are unique to the individual patient, while shared antigens like MAGE-A4 provide targets for broader populations (NIH: PMC5548293). Therapeutic strategies including personalized mRNA vaccines, TCR-engineered T-cells, and bispecific T-cell engagers (ImmTACs) are designed to bind these specific peptide-HLA signatures to induce a potent and selective anti-tumor immune response (Nature: 10.1038/s41586-019-1343-2). Because HLA molecules are highly polymorphic, these therapies are frequently restricted to patients with specific alleles, most commonly HLA-A*02:01, and require precise patient screening for both the HLA type and the presence of the target antigen (ClinicalTrials.gov: NCT03897881). Successful clinical applications, such as tebentafusp for uveal melanoma, highlight the potential of targeting these complexes to overcome traditional treatment resistance.

Other names

Tumor-associated antigens (TAA)Melanoma-associated antigens (MAA)NeoantigensCancer-testis antigens (CTA)Peptide-MHC complex (pMHC)HLA-restricted tumor peptidesTumor-specific antigens (TSA)

Therapeutic agents target these complexes by either providing synthetic peptides to induce endogenous T-cell expansion (vaccines) or by using engineered receptors (TCR-T or bispecifics) that bind the specific peptide-HLA complex to trigger T-cell mediated lysis of the tumor cell.