Mucin 1 peptide-HLA class I complex (MUC1-HLA-I)

Mucin 1 (MUC1) is a transmembrane glycoprotein that is normally expressed on the apical surface of epithelial cells, where it provides a protective barrier. In many adenocarcinomas, MUC1 is overexpressed, loses its polarized distribution, and undergoes aberrant glycosylation, making it a prominent tumor-associated antigen. Intracellular processing of the MUC1 protein results in the generation of specific peptides that are loaded onto Human Leukocyte Antigen (HLA) class I molecules and presented on the cell surface to CD8+ T cells (PMID: 22134412). These MUC1 peptide-HLA complexes are distinct from the bulky, glycosylated extracellular domain of the protein and represent highly specific targets for immunotherapy. Targeting the MUC1 peptide-HLA complex allows for the development of precision therapies such as T-cell receptor (TCR) engineered T cells and TCR-like monoclonal antibodies. These approaches aim to bypass the immunosuppressive effects of the MUC1 glycoforms and the physical barrier created by the MUC1 mucin layer. By specifically recognizing the peptide-HLA complex, these drugs can direct a potent cytotoxic immune response against malignant cells while minimizing damage to healthy tissues that do not present the same peptide density or HLA configuration (PMID: 32810417, 25611625).

Other names

MUC1 peptide-MHC class I complexMUC1-derived peptide-HLA complexMUC1-HLA-A*02:01 complexMUC1-HLA-A2CD227-HLA complex

Therapeutic agents targeting this complex typically utilize T-cell receptor (TCR) engineered T cells or TCR-like antibodies to recognize the specific MUC1 peptide fragment nested within the HLA class I groove. This recognition triggers T-cell mediated cytotoxicity, leading to the release of perforins and granzymes that induce apoptosis in the target tumor cell (PMID: 30552151, 11160694).