Table 1.

H. pylori infection in C57BL/6 wild-type and MHC mutant micea

Mouse strainInfection levelbNo. of mice positive/total no.cQuantitative H. pylori cultured
C57BL/6 wild type1.51 ± 0.4110/101.12 ± 0.37
β2m−/− MHC class I deficient1.87 ± 0.5210/102.41 ± 0.38e
Abβ MHC class II deficient2.14 ± 0.549/102.59 ± 0.55f
  • a Mice were challenged per os with 106 CFU of H. pylori SS1. After 2 weeks, gastric tissues were examined for infection level by a quantitative urease assay.

  • b Mean OD550 ± standard error of the mean for each group of 10 mice.

  • c A positive urease test indicative of H. pylori infection was defined as an OD550 >2 standard deviations above the group mean OD550 from unchallenged control mice.

  • d Culture was performed on segments of gastric tissue at 2 weeks after H. pylori challenge as described in Materials and Methods. The values represent the mean CFU (105) ± the standard error of the mean for each group.

  • e P = 0.017 by Wilcoxon rank sum analysis compared with C57BL/6 wild-type mice.

  • f P = 0.025 by Wilcoxon rank sum analysis compared with C57BL/6 wild-type mice.