Mechanisms of H. pylori Colonization and Pathogenesis

Helicobacter pylori exemplifies a highly adapted pathogen capable of persisting in the hostile gastric environment through a multistep infection process. This chapter systematically delineates the mechanisms underpinning its colonization and subsequent tissue damage. Initial survival is mediated by acid resistance mechanisms, including urease activity, while adhesive structures such as flagella, chemotaxis systems, and outer membrane proteins (e.g., BabA, SabA, HopQ) enable niche establishment. Upon colonization, virulence factors including CagA, VacA, and outer membrane vesicles disrupt host cell integrity, provoke inflammation, and manipulate immune responses, driving pathologies from gastritis to cancer. Heat shock proteins and gamma-glutamyl transpeptidase further augment bacterial resilience and host injury. The coordinated action of these molecules highlights H. pylori’s sophistication in evading host defenses and promoting chronic disease. Understanding these mechanisms provides critical insights for developing targeted diagnostics and therapeutics against H. pylori-associated disorders.