Mucin 1 VNTR-derived peptide-MHC complex (MUC1 VNTR-pMHC)

Mucin 1 (MUC1) is a high-molecular-weight transmembrane glycoprotein that is normally expressed on the apical surface of ductal epithelial cells, where it is heavily O-glycosylated to provide a physical barrier (Nath & Mukherjee, 2014). In many cancers, particularly adenocarcinomas, MUC1 is overexpressed, loses its apical restriction, and exhibits aberrant hypoglycosylation, which exposes the protein core of its Variable Number Tandem Repeat (VNTR) region (Wurz et al., 2014). Peptides derived from this VNTR region are processed and presented on the cell surface by Major Histocompatibility Complex (MHC) molecules, such as HLA-A*02:01, creating a unique tumor-associated antigen (TAA) complex (Tang et al., 2022). These MUC1 VNTR-derived peptide-MHC complexes are targeted by various immunotherapeutic modalities, including peptide-based vaccines like Tecemotide and viral vector vaccines like TG4010, which aim to stimulate a cytotoxic T-cell response (Finn, 2017). Additionally, novel approaches such as T-cell receptor (TCR)-engineered T cells and TCR-like antibodies are being developed to specifically recognize these pMHC complexes, allowing for the selective destruction of malignant cells while minimizing impact on healthy tissues where the MUC1 epitopes are masked by glycans (Zhao et al., 2016).

Other names

MUC1 peptide-HLA complexMUC1 VNTR-derived epitopesMUC1-derived MHC-restricted antigenMUC1 tumor-associated antigen epitopes

Induction of antigen-specific cytotoxic T-lymphocyte (CTL) responses and direct T-cell mediated lysis of tumor cells presenting the MUC1 peptide-MHC complex.