Proliferative populations in intestinal metaplasia: evidence of deregulation in Paneth and goblet cells, but not endocrine cells

In the small intestinal mucosa, four principal epithelial cell lineages are found - the Paneth, goblet, enterocytic, and endocrine cell lineages. Thes e cell lineages are terminally differentiated, non-proliferative, and deriv e from multipotent stem cells near the bases of the crypts of Lieberkuhn. I ntestinal metaplasia of the stomach is considered to be a premalignant cond ition, Since proliferative populations in this condition are not well studi ed, this feature was examined using double-labelling immunohistochemical an d histochemical methods; 20 paraffin blocks of small intestinal mucosa and 24 paraffin blocks of intestinal metaplasia of the human stomach were studi ed. Double-staining was carried out with MIB-1 as a proliferation marker, w ith Alcian blue for goblet cells, anti-chromogranin A for endocrine cells, and p-dimethylaminobenzaldehyde-nitrite for Paneth cells. Double-labelling showed that numerous Paneth cells and goblet cells in intestinal metaplasia mere in the cell cycle, but endocrine cells appeared non-proliferative. Do uble-labelled Paneth or endocrine cells were not seen in the control small intestinal mucosa but scanty double-labelled goblet cells were observed in normal intestinal mucosa, In intestinal metaplasia of the stomach, there is evidence of cell-cycle deregulation in the goblet and Paneth cell lineages , These observations have considerable implications for the biology and his togenesis of Paneth cells, goblet cells, and endocrine cells, and the natur e of intestinal metaplasia in the gastric mucosa. Copyright (C) 2000 John W iley & Sons, Ltd.