AIMS The relationship between Helicobacter pylori (Hp) and gastric epithelia in chronic gastritis and in petic ulcer was studied by transmission electron mi- croscopy (TEM). METHODS Seventy-five gastric antral biopsy speci- mens from the patients examined by six other methods for Hp were fixed in glutaraldehyde and treated with tanin acid before OsO_4 staining than routinely prooessed for TEM studies (at least 4 semi- thin sections oriented for ultrathin sections in each sample). RESULTS The bacilli were detected by TEM within gastric mucosa in 53 of 55 patients infected with Hp. Ultrathin sections especially stained with tanin acid re- vealed clearly glycocalyx by which the bacillus was connected with the epithelium. As the bacilli grouped as colony and breed,the adjacent mucous cells degerated and characterized by erosion of the juxtalu- minal cytoplasm,vacuolation or blebs,even desqua- mation of cell. Evidence was accumulated to show that the baoilli were located in the lumen attracted neu- trophils which intended to migrate into intercellular space of epithelia or into the lumen to exert the effect of Hp phagocytosis. CONCLUSIONS The sensitivity and specificity of Hp diagnosis by TEM is respectively 96% and 95%. Tanin acid is suitable for the preservation of glycocalyx of cell. The colonized bacilli,usually with the wide periplasmic pools,contributed to the spectrum degen- eration of epithelia,including mucous neck cells. If Hp infection persists,the degeneration and regeneration of mucous neck cells alternatively carried on and ultimate- ly the generative stem cells were damaged,as the result,the chronic atrophy gastritis could occure.
