Helicobacter pylori Outer Inflammatory Protein A (OipA) suppresses apoptosis of AGS gastric cells in vitro

This study aims to elucidate the role of OipA in H. pylori infection using clinical strains harboring oipA “on” and “off” motifs. Proteomics analysis was performed on AGS cell pre and post‐infection with H. pylori oipA “on” and “off” strains, using liquid chromatography / mass spectrometry. AGS apoptosis and cell cycle assays were performed. Moreover, expression of vacuolating cytotoxin A (VacA) was screened using Western blotting. AGS proteins that have been suggested previously to play a role or associated with gastric disease were down‐regulated post‐infection with oipA “off” strains comparing to oipA “on” strains. Furthermore, oipA “off” and ΔoipA cause higher level of AGS cells apoptosis and G0/G1 cell‐cycle arrest than oipA “on” strains. Interestingly, deletion of oipA increased bacterial VacA production. The capability of H. pylori to induce apoptosis and suppress expression of proteins having roles in human disease in the absence of oipA suggests that strains not expressing OipA may be less virulent or may even be protective against carcinogenesis compared those expressing OipA. This potentially explains the higher incidence of gastric cancer in East Asia where oipA “on” strains predominates.

Source: Cellular Microbiology - August 1, 2017 Category: Microbiology Authors: Anis Rageh Al ‐Maleki, Mun Fai Loke, Sook Yin Lui, Nur Siti Khadijah Ramli, Yalda Khosravi, Chow Goon Ng, Gopinath Venkatraman, Khean‐Lee Goh, Bow Ho, Jamuna Vadivelu Tags: RESEARCH ARTICLE Source Type: research