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

Mucin 1 (MUC1) peptide–Major Histocompatibility Complex (pMHC) refers to the presentation of MUC1-derived antigenic peptides within the binding groove of MHC molecules on the surface of cells, notably dendritic cells and tumor cells. MUC1 is a transmembrane glycoprotein that is frequently overexpressed and under-glycosylated in various cancers, leading to the exposure of immunogenic peptide sequences that are processed and presented as pMHC complexes (Nath & Mukherjee, 2014). On dendritic cells, these complexes serve as the primary signal for the activation of CD8+ and CD4+ T cells, initiating a targeted anti-tumor immune response (Apostolopoulos et al., 2015). Therapeutic interventions targeting MUC1-pMHC include dendritic cell vaccines, where autologous DCs are loaded with MUC1 peptides to enhance T-cell priming, and advanced modalities like TCR-engineered T cells (TCR-T) or TCR-like antibodies that recognize the specific peptide-MHC configuration (Zhao et al., 2016). This target is particularly valuable because it allows the immune system to recognize intracellular or membrane-bound MUC1 fragments that are otherwise inaccessible to traditional monoclonal antibodies. Clinical development has focused on adenocarcinomas such as breast, lung, and pancreatic cancers, where MUC1-pMHC density is high (Wurz et al., 2014).

Other names

MUC1-HLA complexMUC1 peptide-HLA-A2 complexMUC1-pMHC on dendritic cellsMucin-1-derived peptide-MHC complex

Stimulation of MUC1-specific T-cell responses through the presentation of MUC1 peptides on MHC molecules (active immunotherapy) or direct targeting of the pMHC complex by engineered receptors (passive/adoptive immunotherapy).