EFFECT OF HELICOBACTER-PYLORI ON GASTRIC EPITHELIAL-CELL MIGRATION AND PROLIFERATION IN-VITRO - ROLE OF VACA AND CAGA

Helicobacter pylori infection is associated with inflammation of the g astric mucosa and with gastric mucosal damage. In this study, we sough t to test the hypothesis that two H. pylori virulence factors (VacA an d CagA) impair gastric epithelial cell migration and proliferation, th e main processes involved in gastric mucosal healing in vivo. Human ga stric epithelial cells (MKN 28) were incubated with undialyzed or dial yzed broth culture filtrates from wild-type H. pylori strains or isoge nic mutants defective in production of VacA, CagA, or both products. W e found that (i) VacA specifically inhibited cell proliferation withou t affecting cell migration, (ii) CagA exerted no effect on either cell migration or proliferation, and (iii) undialyzed H. pylori broth cult ure filtrates inhibited both cell migration and proliferation through a VacA- and CagA-independent mechanism. These findings demonstrate tha t, in addition to damaging the gastric mucosa, H. pylori products may also impair physiological processes required for mucosal repair.