Interleukin-33 signaling exacerbates experimental infectious colitis by enhancing gut permeability and inhibiting protective Th17 immunity

Mucosal Immunol. 2021 Jul;14(4):923-936. doi: 10.1038/s41385-021-00386-7. Epub 2021 Mar 2.

Abstract

A wide range of microbial pathogens is capable of entering the gastrointestinal tract, causing infectious diarrhea and colitis. A finely tuned balance between different cytokines is necessary to eradicate the microbial threat and to avoid infection complications. The current study identified IL-33 as a critical regulator of the immune response to the enteric pathogen Citrobacter rodentium. We observed that deficiency of the IL-33 signaling pathway attenuates bacterial-induced colitis. Conversely, boosting this pathway strongly aggravates the inflammatory response and makes the mice prone to systemic infection. Mechanistically, IL-33 mediates its detrimental effect by enhancing gut permeability and by limiting the induction of protective T helper 17 cells at the site of infection, thus impairing host defense mechanisms against the enteric pathogen. Importantly, IL-33-treated infected mice supplemented with IL-17A are able to resist the otherwise strong systemic spreading of the pathogen. These findings reveal a novel IL-33/IL-17A crosstalk that controls the pathogenesis of Citrobacter rodentium-driven infectious colitis. Manipulating the dynamics of cytokines may offer new therapeutic strategies to treat specific intestinal infections.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biomarkers
  • Colitis / etiology*
  • Colitis / metabolism*
  • Colitis / pathology
  • Disease Models, Animal
  • Disease Susceptibility
  • Enterobacteriaceae Infections / complications
  • Enterobacteriaceae Infections / immunology
  • Interleukin-33 / metabolism*
  • Intestinal Mucosa / immunology*
  • Intestinal Mucosa / metabolism*
  • Lymphocyte Count
  • Mice
  • Permeability
  • Signal Transduction*
  • T-Lymphocytes, Regulatory / immunology
  • T-Lymphocytes, Regulatory / metabolism
  • Th17 Cells / immunology*
  • Th17 Cells / metabolism*

Substances

  • Biomarkers
  • Interleukin-33