Dataset Information

Toll-Like Receptor-4 Is Involved in Mediating Intestinal and Extra-Intestinal Inflammation in Campylobacter coli-Infected Secondary Abiotic IL-10^-/- Mice.

ABSTRACT: Human Campylobacter infections are emerging worldwide and constitute significant health burdens. We recently showed that the immunopathological sequelae in Campylobacter jejuni-infected mice were due to Toll-like receptor (TLR)-4 dependent immune responses induced by bacterial lipooligosaccharide (LOS). Information regarding the molecular mechanisms underlying Campylobacter coli-host interactions are scarce, however. Therefore, we analyzed C. coli-induced campylobacteriosis in secondary abiotic IL-10^-/- mice with and without TLR4. Mice were infected perorally with a human C. coli isolate or with a murine commensal Escherichia coli as apathogenic, non-invasive control. Independent from TLR4, C. coli and E. coli stably colonized the gastrointestinal tract, but only C. coli induced clinical signs of campylobacteriosis. TLR4^-/- IL-10^-/- mice, however, displayed less frequently fecal blood and less distinct histopathological and apoptotic sequelae in the colon versus IL-10^-/- counterparts on day 28 following C. coli infection. Furthermore, C. coli-induced colonic immune cell responses were less pronounced in TLR4^-/- IL-10^-/- as compared to IL-10^-/- mice and accompanied by lower pro-inflammatory mediator concentrations in the intestines and the liver of the former versus the latter. In conclusion, our study provides evidence that TLR4 is involved in mediating C. coli-LOS-induced immune responses in intestinal and extra-intestinal compartments during murine campylobacteriosis.

SUBMITTER: Klove S

PROVIDER: S-EPMC7761268 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Toll-Like Receptor-4 Is Involved in Mediating Intestinal and Extra-Intestinal Inflammation in Campylobacter coli-Infected Secondary Abiotic IL-10-/- Mice.

Kløve Sigri S Genger Claudia C Weschka Dennis D Mousavi Soraya S Bereswill Stefan S Heimesaat Markus M MM

Microorganisms 20201127 12

Human Campylobacter infections are emerging worldwide and constitute significant health burdens. We recently showed that the immunopathological sequelae in Campylobacter jejuni-infected mice were due to Toll-like receptor (TLR)-4 dependent immune responses induced by bacterial lipooligosaccharide (LOS). Information regarding the molecular mechanisms underlying Campylobacter coli-host interactions are scarce, however. Therefore, we analyzed C. coli-induced campylobacte ...[more]

PMID: 33261211

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Project description:Campylobacter jejuni infection produces a spectrum of clinical presentations in humans--including asymptomatic carriage, watery diarrhea, and bloody diarrhea--and has been epidemiologically associated with subsequent autoimmune neuropathies. This microorganism is genetically variable and possesses genetic mechanisms that may contribute to variability in nature. However, relationships between genetic variation in the pathogen and variation in disease manifestation in the host are not understood. We took a comparative experimental approach to explore differences among different C. jejuni strains and studied the effect of diet on disease manifestation in an interleukin-10 deficient mouse model.In the comparative study, C57BL/6 interleukin-10-/- mice were infected with seven genetically distinct C. jejuni strains. Four strains colonized the mice and caused disease; one colonized with no disease; two did not colonize. A DNA:DNA microarray comparison of the strain that colonized mice without disease to C. jejuni 11168 that caused disease revealed that putative virulence determinants, including loci encoding surface structures known to be involved in C. jejuni pathogenesis, differed from or were absent in the strain that did not cause disease. In the experimental study, the five colonizing strains were passaged four times in mice. For three strains, serial passage produced increased incidence and degree of pathology and decreased time to develop pathology; disease shifted from watery to bloody diarrhea. Mice kept on an ~6% fat diet or switched from an approximately 12% fat diet to an approximately 6% fat diet just before infection with a non-adapted strain also exhibited increased incidence and severity of disease and decreased time to develop disease, although the effects of diet were only statistically significant in one experiment.C. jejuni strain genetic background and adaptation of the strain to the host by serial passage contribute to differences in disease manifestations of C. jejuni infection in C57BL/6 IL-10-/- mice; differences in environmental factors such as diet may also affect disease manifestation. These results in mice reflect the spectrum of clinical presentations of C. jejuni gastroenteritis in humans and contribute to usefulness of the model in studying human disease.

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Dataset Information

Toll-Like Receptor-4 Is Involved in Mediating Intestinal and Extra-Intestinal Inflammation in Campylobacter coli-Infected Secondary Abiotic IL-10^-/- Mice.

Publications

Toll-Like Receptor-4 Is Involved in Mediating Intestinal and Extra-Intestinal Inflammation in <i>Campylobacter coli</i>-Infected Secondary Abiotic IL-10<sup>-/-</sup> Mice.

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