Mucin 1-derived peptide–Major Histocompatibility Complex (MUC1-pMHC) (MUC1-pMHC)

Mucin 1 (MUC1) is a transmembrane glycoprotein that is frequently overexpressed and aberrantly glycosylated in various epithelial cancers, making it a significant tumor-associated antigen (PMID: 21684320). The MUC1-derived peptide–MHC complex specifically refers to the presentation of MUC1 antigenic fragments by Major Histocompatibility Complex (MHC) molecules, typically HLA-A2, on the surface of cells such as plasmacytoid dendritic cells (pDCs) (PMID: 32823934). In the context of immunotherapy, pDCs are utilized for their superior ability to prime and activate cytotoxic T lymphocytes (CTLs) due to their high expression of MHC and co-stimulatory molecules (PDC*line Pharma). These complexes serve as the primary target for T-cell receptors (TCRs) or TCR-like antibodies, which recognize the specific peptide-HLA combination to initiate an immune response (PMID: 25609550). Therapeutic strategies, such as the PDC*lung01 vaccine, leverage these complexes on specialized pDC lines to induce a robust, tumor-specific T-cell expansion in patients with MUC1-positive malignancies (PDC*line Pharma). By focusing on the pMHC complex, these therapies aim to overcome the immunosuppressive tumor microenvironment and enhance the precision of the anti-tumor immune attack (PMID: 32823934).

Other names

MUC1-derived peptide–MHC complexes on plasmacytoid dendritic cellsMUC1 peptide-HLA complexMUC1-pMHC complexMUC1 antigen-MHC complexMUC1-HLA-A*02:01 complex

The MUC1-pMHC complex on plasmacytoid dendritic cells acts as a specific ligand for T-cell receptors (TCRs) on CD8+ cytotoxic T lymphocytes. This interaction, facilitated by the high density of co-stimulatory molecules on the pDC surface, triggers the activation and clonal expansion of MUC1-specific T cells, which then circulate to identify and lyse MUC1-expressing tumor cells (PMID: 32823934, PDC*line Pharma).