Helicobacter pullorum outbreak in C57BL/6NTac and C3H/HeNTac barrier-maintained mice

Abstract

Helicobacter pullorum is a bacterial pathogen in humans. By using microaerobic culture techniques, H. pullorum was isolated from the feces of barrier-maintained mice and identified, on the basis of biochemical, restriction fragment length polymorphism, and 16S rRNA gene sequence analyses. This finding presents an opportunity to study H. pullorum pathogenesis in mice.

FIG. 1.

Both H. pullorum mouse isolates MIT 09-6634 and MIT 09-6635 were 99.9% similar to H. pullorum human isolate NCTC 12826 and 99.4% similar to chicken isolate NCTC 12824. They were 98.4% similar to H. canadensis strain NLEP 16143, the next closest species. The scale bar shows 5% sequence differences as measured by the sum of the horizontal distances connecting taxa.

FIG. 2.

Restriction fragment length polymorphism analysis patterns of the Helicobacter 16S rRNA gene with AluI and HhaI digestion. Lanes 1 to 3, Helicobacter isolates from Taconic mice; lane 4, H. pullorum human isolate MIT 98-5489; lane 5, H. typhlonius; lane 6, H. bilis; lane 7, H. muridarum; lane 8, H. hepaticus; lane 9, H. rodentium; M, 100-bp DNA ladder.

FIG. 3.

Cytolethal distending toxin assay. Images demonstrate effects consistent with Cdt activity, including giant cell formation, nuclear enlargement and fragmentation, and multinucleation. (A) Control; (B) H. cinaedi; (C) H. pullorum. (D) PCR results with H. pullorum cdtB species-specific primers. Lane M, 1-kb Plus DNA ladder; lanes 2 and 3, bacterial DNA of H. pullorum isolates from mice; lanes 4, 5, and 6, fecal DNA from H. pullorum-infected mice; lane 7, H. pullorum human isolate MIT 98-5489.