[Detection of the epithelial membrane antigen in patients with varying status of the gastric mucosa using monoclonal antibodies].

To study how the normal gastric mucosa develops chronic gastritis, gastric ulcer or cancer, biopsies from 103 patients with non-tumor gastric diseases and operative specimens from 12 patients with stomach carcinoma were examined for epithelial antigen (EA). In the peroxidase-antiperoxidase reaction performed on paraffin-embedded and cryostat sections of the gastric mucosa, monoclonal antibodies (MAb) to antigens located on the membranes of fatty breast milk globules were employed, which had been presented by the Department of Biomedical Sciences, Tampere University (Finland). The MAb 111C12-identified antigenic determinant was found to occur in 12.8% of the nonmalignant gastric mucosa examined and 48% of the stomach carcinoma one. The detection of EA is not characteristic of the given portion of the gastric mucosa in carcinoma.