Analysis of the Relationship between Invasive Capability of Helicobacter pylori and Gastroduodenal Diseases.

This study aims to reveal the roles of internalized H. pylori in the bacterial pathopoiesis. Transmission electron microscopic was used to observe the invasion of H. pylori. Invasion rates of H. pylori ( 2 standard strains and 43 clinical strains) were examined by gentamicin invasion assay. The cagA, cagE and vacA genes of H. pylori were detected by PCR. And the cagA 3´region (cagA-EPIYA) of each strains was sequenced. The secretion of IL-8 from AGS and activity of NF-κB induced by intracellular H. pylori were tested by ELISA and the Dual-Luciferase reporter assay system, respectively. It was found that H. pylori could adhere and invade into AGS cells, then continue to survive and multiply in cytoplasm. The average invasion rate of H. pylori gastric cancer plants and that of ulcer plants were both higher than that of gastritis plants (P≈0.0001). And in the clinical strains, cagA, vacA and cagE were all positive, cagA-EPIYA genotypes included ABD 90.7% (39/43) and ABBD 9.3% (4/43), all without comparability. But notablely, average invasion rate of H. pylori vacA s1c-i1-m1b plants was higher than that of vacA s1c-i1-m2 plants (P=0.0445). In addition, the intracellular H. pylori all can induce IL-8 secretion, which would decreased after cells were pretreated with anti-β1-integrin antibody or SN-50 (a NF-κB inhibitor). And the intracellular H. pylori all activated NF-κB, which would be inhibited after cells were pretreated with anti-β1-integrin antibody. PMID: 257...
Source: Journal of Medical Microbiology - Category: Microbiology Authors: Tags: J Med Microbiol Source Type: research