Determinants of Helicobacter pylori pathogenicity.

Helicobacter pylori is a recently recognized bacterial pathogen associated with diverse pathologies of varying severity, such as chronic gastritis, peptic ulceration, mucosa-associated lymphoid tissue (MALT) lymphoma, and gastric carcinoma. We here present a review of our current knowledge on the properties of H. Pylori that adapt it to its particular niche by allowing it to survive in the stomach and to colonize the gastric mucosa, as well as those that underlie its persistence and pathogenicity. While the bacterial determinants that preclude the persistent colonization of the gastric mucosa are better understood, those associated with pathogenicity appear to result from the possibility for some of the bacteria of the species to synthesize products that directly or indirectly damage the gastric mucosa, cause a persistent inflammatory reaction, and/or perturb the regulation of acid secretion.