title: Microbiota Composition and Immune Responses DuringCampylobacter JejuniInfection in Conventionally Colonized IL-10-/-Mice Lacking Nucleotide Oligomerization Domain 2.
abstract: Host immune responses are pivotal for combating enteropathogenic infections. We here assessed the impact of the innate receptor nucleotide oligomerization domain protein 2 (NOD2) in murineCampylobacter jejuni-infection. Conventionally colonized IL-10-/-mice lacking NOD2 and IL-10-/-controls were perorally challenged withC. jejunistrain 81-176 and displayed comparable pathogenic colonization of intestines until day 14 postinfection (p.i.). Whereas overall intestinal microbiota compositions were comparable in naive mice, NOD2-/-IL-10-/-mice exhibited less fecal bifidobacteria and lactobacilli than IL-10-/-counterparts after infection. Interestingly, NOD2-/-IL-10-/-mice were clinically more compromised during the early phase of infection, whereas, conversely, IL-10-/-animals exhibited more frequently bloody feces lateron. While colonic apoptotic cell and T lymphocyte numbers were comparable in eitherC. jejuni-infected mice, B lymphocytes were lower in the colon of infected NOD2-/-IL-10-/-mice versus controls. At day 14 p.i., colonic TNF and IL-23p19 mRNA levels were upregulated in NOD2-/-IL-10-/-mice only. Translocation rates of intestinal commensals to mesenteric lymphnodes and extra-intestinal compartments including liver and kidney were comparable, whereas viable bacteria were more frequently detected in spleens derived from IL-10-/-as compared to NOD2-/-IL-10-/-mice. In conclusion, NOD2 is involved duringC. jejuniinfection in conventionally colonized IL-10-/-mice in a time-dependent manner.
authors.affiliation: Department of Microbiology and Hygiene, Charité - University Medicine Berlin , Berlin, Germany.
authors.forename: Markus M
authors.initials: MM
authors.lastname: Heimesaat
authors.affiliation: Department of Microbiology and Hygiene, Charité - University Medicine Berlin , Berlin, Germany.
authors.forename: Ursula
authors.initials: U
authors.lastname: Grundmann
authors.affiliation: Department of Microbiology and Hygiene, Charité - University Medicine Berlin , Berlin, Germany.
authors.forename: Marie E
authors.initials: ME
authors.lastname: Alutis
authors.affiliation: Department of Microbiology and Hygiene, Charité - University Medicine Berlin , Berlin, Germany.
authors.forename: André
authors.initials: A
authors.lastname: Fischer
authors.affiliation: Department of Microbiology and Hygiene, Charité - University Medicine Berlin , Berlin, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Bereswill
keywords: Campylobacter jejuni; IL-10–/– infection model; IL-23/IL-22/IL-18 axis; bacterial translocation; bifidobacteria; colonization resistance; intestinal microbiota; lactobacilli; nucleotide oligomerization domain-2; pro-inflammatory immune responses