THE IDENTIFICATION, ISOLATION AND CHARACTERIZATION OF A 67-KILODALTON, PNA-REACTIVE AUTOANTIGEN COMMONLY EXPRESSED IN HUMAN ADENOCARCINOMAS

In an attempt to characterize a Peanut Agglutinin (PNA) autoantigen wi dely expressed in common human adenocarcinomas, monoclonal antibodies (MAbs) were made against PNA-affinity purified glycoproteins from pool ed breast cancer membrane biopsy materials. Two IgM MAbs, 167H.1 and 1 67H.4, were found to react strongly with frozen tissue sections of var ious adenocarcinomas and the antigen was characterized further. By imm unoprecipitation, western blotting, and gel filtration, both MAbS were found to react with a 67 kilodalton (kD) antigen. The 67 kD antigen w as purified and determined to be specifically PNA reactive and natural ly occurring antibodies were demonstrated to the purified antigen. In conclusion, the 167H.1 and 167H.4 MAbs identify a non-mucinous, PNA-re active autoantigen widely expressed in human adenocarcinomas.