Inoculation of barrier-born pigs with Helicobacter pylori: a useful animal model for gastritis type B.

At the age of 8 weeks, 15 barrier-born pigs, specific pathogen free, were inoculated intragastrically with suspensions of 10(7) to 10(10) CFU of Helicobacter pylori after pretreatment with omeprazole. The pigs were observed for up to 12 weeks, endoscopic biopsy specimens were taken, and serum samples were drawn. H. pylori was identified by routine culturing and by staining with an H. pylori-specific monoclonal antibody on cryostat sections of gastric biopsy specimens. In 11 of 15 inoculated pigs, H. pylori was detected throughout the observation period. In these infected pigs, there was an antibody response to H. pylori, as determined in serum by an enzyme immunoassay. Furthermore, the development of superficial, focal gastritis with infiltrates of mononuclear class II antigen-expressing lymphocytes was observed immunohistologically. H. pylori was never detected and an antibody response to H. pylori was not observed in two control pigs. The development of gastritis and the systemic antibody response to H. pylori support the usefulness of this animal model for studies of H. pylori-related human diseases.