Helicobacter pylori-infected Japanese monkeys

Conclusion It is possible to establish persistentH. pylori infection in the gastric mucosa of Japanese monkeys and create acute and chronic gastritis similar to that found in humans; persistent infection causes atrophic changes in the gastric mucosa. Japanese monkeys, which age approximately flve times faster than humans, provide a valuable model for investigating the long-term effects ofH. pylori infection on the gastric mucosa and for the study of stages in the development of gastric cancer. H. pylori produces gastritis resulting in both local inflammation and a systemic immune response. Genes have been isolated that code for cytotoxic proteins such as CagA, VacA, and for heat-shock protein. A number of points remain unresolved concerning the pathology ofH. pylori infection, known to be closely related to the recurrence of peptic ulcers. Routes of infection are fecaloral and oral-oral, and humans can be infected from pets.⁵³ Gastroendoscopy can be a source of nosocomial infections. The natural habitat ofH. pylori in humans is limited almost exclusively to the surface layer of the gastric mucosa; it is rarely found in other locations. In the future, we should develop chemotherapeutic methods for curingH. pylori infections and a vaccine for their prevention. The present study was conducted in accordance with Oita Medical University guidelines for animal experimentation.