[Pathogenicity of hp jhp947 gene to C57BL/6 mice].

Objective: To study the effects of Helicobacter pylori jhp947 gene on the pathogenesis of epithelial cells and gene express pattern by animal studies.
Methods: Twenty-seven special pathogen free (SPF) C57BL/6 mice were divided equally into 3 groups, and challenged with Helicobacter pylori J99, Helicobacter pylori deltaJ99-947 and phosphate buffer (PBS) respectively, at a dose of 10(9) colony formine unit (CFU) at 0, 2, and 4 days. Mice were sacrificed 4 weeks after the last challenge, and went through rapid urease test, culture of Hp, histological examination, immunofluorescent histochemistry and semiquantitative reverse transcription PCR (RT-PCR) of gastric mucosa.
Results: The result of rapid urease test and culture of Hp indicated that the positive rates in J99 and deltaJ99-947 group were both 100% while 0% in PBS group. The result of histology examination indicated that garstric mucosa is all normal in PBS group; in J99 group, 33.3% (3/9) had slightly anabrosis, 66.7% (6/9) had seriously anabrosis; in deltaJ99-947 group, 22.2% (2/9) is normal, 77.8% (7/9) had slightly anabrosis. The degree of anabrosis seems to be more severe in J99 than in deltaJ99-947. The result of immunofluorescent histochemistry and semiquantitative RT-PCR of gastric mucosa indicated that the expression level of ets homologous factor, N-myc downstream regulated gene 1, methylthioadenosine phosphorylase is significantly lower in J99 than in deltaJ99-947 group (P < 0.05).
Conclusion: The degree of anabrosis seems to be more severe in Hp with jhp947 gene than in Hp without jhp947 gene. In vivo, jhp947 may induce tumorigenesis by inhibiting anti-oncogenes (N-myc downstream regulated gene 1 and methylthioadenosine phosphorylase).