[Analysis of virulence factors of Helicobacter pylori]

Many virulence factors of Helicobacter pylori have been reported. Analysis of such virulence factors in relation to the occurrence of gastroduodenal diseases is discussed. Several adhesins of H. pylori are involved in its adhesion to gastric epithelial cells, and urease activity is necessary for its colonization in acidic gastric mucosa. Vacuolation cytotoxin(VacA)-positive Type I strains are frequently isolated from the patients with peptic ulcer diseases in western countries, but not in east Asia. CagA has been reported to be transported into epithelial cells through type IV secretion machinery coded by genes in cag pathogenicity island(PAI) and phosphorylated by cellular tyrosine kinase. Heat shock protein is also considered to be a virulence factor to play a role of triggering autoimmune response, stimulating its adhesion and inducing several cytokines.