IMMUNOHISTOCHEMICAL AND IN-SITU HYBRIDIZATION STUDIES OF BETA-MICROSEMINOPROTEIN IN THE HUMAN GASTRIC-MUCOSA

beta-Microseminoprotein is a 10-kDa disulphide-rich protein with unkno wn function which is present in the mucus of the airways, gastrointest inal tract and urogenital tract. In this paper, an investigation of th e distribution of microseminoprotein in the human stomach is reported. Immunohistochemistry and in situ hybridization were used. beta-Micros eminoprotein was found to be localized mainly in the antrum part of th e stomach and in two types of cells. Cells of the most abundant type ( designated M-cells) were the neutral mucin-containing cells in the bot tom part of the gastric glands and the surface epithelium. Virtually a ll these cells contained both beta-microseminoprotein mRNA and protein product. Cells of the second type (designated E-cells) were found in a zone one-third up from the bottom of the gastric glands, where gastr ic endocrine cells are located. The E-cells were fewer than the M-cell s and usually solitary. They seemed to have a high concentration of pr otein compared with their low mRNA level. The majority of the E-cells contained chromogranin A and gastrin. The observations made have impli cations for the understanding of the differentiation of the mucosal ce lls in the antrum of the stomach and form a basis for future studies o f beta-microseminoprotein in gastric disease.