Association of gastric epithelial apoptosis with the ability of Helicobacter pylori to induce a neutrophil oxidative burst

Both polymorphonuclear cell infiltration and increased epithelial apoptosis are seen in gastric mucosa in the presence of Helicobacter pylori infectio n. This study examined the association between bacterial ability to stimula te an oxidative burst in neutrophils and epithelial apoptosis. Biopsy speci mens were obtained from 15 patients to detect apoptotic cells by the TUNEL method. H. pylori strains isolated from corresponding stomach biopsy sample s were tested for the ability to stimulate an oxidative burst in human neut rophils. Neutrophils were isolated from healthy subjects without H. pylori infection and the oxidative burst was measured by flow cytometry with dichl orofluorescein diacetate. Stimulation with H. pylori increased both the per centage of activated cells and fluorescence intensity. There was a signific ant positive correlation between the number of epithelial apoptotic cells a nd fluorescence intensity. Increased neutrophil oxidative burst stimulated by H. pylori may play a role in enhanced gastric mucosal DNA damage and con sequent atrophic gastritis and gastric cancer.