Does Helicobacter pylori disrupt gastric mucosal physiology through epithelial injury and local inflammation even without major virulence genes?

Helicobacter pylori infection is well established as a cause of chronic active gastritis and can compromise epithelial integrity. The broader assertion that it disrupts gastric mucosal physiology in the absence of major virulence determinants is biologically credible, but is more directly supported for inflammation and barrier-related effects than for every physiological endpoint.

Clinical and inflammatory evidence

• Human gastric-biopsy studies show cellular infiltration and histologic gastritis during H. pylori infection, including infections negative for CagA/VacA markers. Infections with triple-negative profiles for cagA, babA2, and the vacA s1 allele had mucosal IL-8 expression 7.4-fold higher than uninfected controls.
• Thus, absence of selected canonical virulence markers does not prevent a local inflammatory response, although marker-positive infections generally produce more severe inflammation.

Epithelial injury and mucosal-barrier mechanisms

• H. pylori can injure gastric epithelium through multiple routes: adhesion-mediated persistence, urease-associated effects on mucus/barrier responses, VacA-associated vacuolation and reduced epithelial viability, and HtrA-mediated cleavage of E-cadherin.
• E-cadherin disruption and impaired epithelial junctions provide a mechanistically coherent pathway to altered barrier physiology. In epithelial monolayers, wild-type organisms weakened the normal acid-induced barrier-strengthening response in a urease-dependent manner.
• Inflammation may amplify injury through IL-8 signaling and recruited immune cells, but its physiological consequences are endpoint-specific.

Interpretation

• A key boundary is that a cagA-deficient strain could induce IL-8 without suppressing gastric H+/K+-ATPase expression or acid secretion. Therefore, inflammation does not imply uniform impairment of acid secretory physiology.

Bottom line

• H. pylori reliably causes local gastric inflammation and can damage epithelium; these processes can plausibly disturb barrier-related mucosal physiology even when selected major virulence genes are absent. Broad disruption across all gastric physiological functions in strains lacking a full virulence-gene panel remains less directly established.