IMMUNOGENICITY OF THE HYDROPHILIC REGION OF THE MUC1 MUCIN PROTEIN CORE

This report is an analysis of data relating to the epitopes of 28 muri ne monoclonal antibodies reactive with the protein core of human carci noma-associated MUC1 mucins. All anti-MUC1 antibodies define epitopes of linear sequences of 3, 4 or 5 amino acids within the hydrophilic do main, APDTRPAP, which is expressed multiple times in a highly conserve d 20 amino acid repeat sequence of the MUC1 core. The R residue is pre sent in the epitopes defined by all of the 28 anti-MUC1 monoclonal ant ibodies. Epitopes of antibodies originally prepared against immunogens containing human milk fat globule membranes include the motif DTR in over 90% of the examples studied.