felis infected CD73−/− mice the severity of gastritis and proinflammatory cytokine levels were increased, and H. felis colonization levels reduced, when compared with WT mice [32]. FVB/N mice deficient

in multidrug resistance gene 1a (mdr1a) gene expression developed spontaneous colitis in 3–4 months. To investigate the role of host genetic background on susceptibility to spontaneous colitis, Staley et al. backcrossed the mdr1a genetic mutation, which results in P-glycoprotein deficiency, onto a C57BL/6J mouse strain; however, these mice did not develop spontaneous colitis. To determine whether they had increased susceptibility HSP assay to colitis induction following a 2nd insult, B6.mdr1a−/− mice were treated with dextran sulfate sodium (DSS) and H. bilis. When compared with B6 mice treated with DSS, treated

B6.mdr1a−/− mice had increased histologic inflammation, colonic shortening, fecal blood, and reduced body weight, while H. bilis treatment failed to induce colitis [33]. Gulani et al. investigated the effect of H. hepaticus colonization on the specific antibody and T-cell-mediated responses to intranasal inoculation with Herpes Simplex Virus (type 1), and on the phenotypic and functional characteristics of dendritic cells (DC) using H. hepaticus-free and infected mice. Surface expression of the maturation-associated markers CD40, CD80, CD86, and MHCII and

the percentages of IL-12p40 and TNFα-producing DC in the colic lymph nodes of H. hepaticus-infected Crizotinib clinical trial mice were decreased when compared with controls. The authors concluded that Helicobacter-free mice should be used in all immunologic studies [34]. In addition, Hylton et al. [35] reported chronic low levels of Helicobacter infection in mice to modulate the response to hemorrhage-induced intestinal Phosphoglycerate kinase damage from a complement-mediated response to a macrophage response. Loman et al. [36] have suggested that the current taxonomy of H. canadensis should be re-evaluated based on their recent sequencing of the complete genome of H. canadensis (type strain NCTC13241; accession number CM00776) and on observed phylogenetic discordances. Twenty-nine homopolymeric tract-associated coding regions indicative of phase variation have been identified in the H. canadensis genome, including five candidate transcriptional phase variable coding sequences (CDSs), 16 candidate translational phase variable CDSs, and eight candidate C-terminal phase variable CDSs that would impact on the function, specificity or antigenicity of the products [37]. Okoli et al. investigated protein expression profiles of H. hepaticus grown in bovine bile using two-dimensional gel electrophoresis and tandem mass spectrometry.