HUMAN B-CELL IMMUNE-RESPONSE TO THE POLYMORPHIC EPITHELIAL MUCIN

Human antibodies generated by Epstein-Barr virus immortalized B-cells from tumor-draining lymph nodes of an ovarian cancer patient were scre ened for reactivity in enzyme-linked immunosorbent assay with a synthe tic peptide corresponding to the protein core of the polymorphic epith elial mucin. Epitopes within this region are in fact considered tumor specific since they are selectively exposed in tumor cells due to aber rant glyosylation. Human antibody BB5, thus selected, reacts in enzyme -linked immunosorbent assay and immunohistochemistry with polymorphic epithelial mucin-expressing tumor cells. This is the first demonstrati on of the existence of a B-cell immune response to selected epitopes o f polymorphic epithelial mucin and, together with the cytotoxic T-cell response already demonstrated, constitutes the basis for the use of s ynthetic peptides as a vaccine in cancer patients.