title: Regulatory T cells promote a protective Th17-associated immune response to intestinal bacterial infection with C. rodentium.
abstract: Intestinal infection with the mouse pathogen Citrobacter rodentium induces a strong local Th17 response in the colon. Although this inflammatory immune response helps to clear the pathogen, it also induces inflammation-associated pathology in the gut and thus, has to be tightly controlled. In this project, we therefore studied the impact of Foxp3(+) regulatory T cells (Treg) on the infectious and inflammatory processes elicited by the bacterial pathogen C. rodentium. Surprisingly, we found that depletion of Treg by diphtheria toxin in the Foxp3(DTR) (DEREG) mouse model resulted in impaired bacterial clearance in the colon, exacerbated body weight loss, and increased systemic dissemination of bacteria. Consistent with the enhanced susceptibility to infection, we found that the colonic Th17-associated T-cell response was impaired in Treg-depleted mice, suggesting that the presence of Treg is crucial for the establishment of a functional Th17 response after the infection in the gut. As a consequence of the impaired Th17 response, we also observed less inflammation-associated pathology in the colons of Treg-depleted mice. Interestingly, anti-interleukin (IL)-2 treatment of infected Treg-depleted mice restored Th17 induction, indicating that Treg support the induction of a protective Th17 response during intestinal bacterial infection by consumption of local IL-2.
authors.affiliation: Institute of Infection Immunology, TWINCORE, Centre for Experimental and Clinical Infection Research; a joint venture between the Medical School Hannover (MHH) and the Helmholtz Centre for Infection Research (HZI), Hannover, Germany.
authors.forename: Z
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Institute of Infection Immunology, TWINCORE, Centre for Experimental and Clinical Infection Research; a joint venture between the Medical School Hannover (MHH) and the Helmholtz Centre for Infection Research (HZI), Hannover, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Friedrich
authors.affiliation: Institute of Infection Immunology, TWINCORE, Centre for Experimental and Clinical Infection Research; a joint venture between the Medical School Hannover (MHH) and the Helmholtz Centre for Infection Research (HZI), Hannover, Germany.
authors.forename: S C
authors.initials: SC
authors.lastname: Hagemann
authors.affiliation: Institute of Infection Immunology, TWINCORE, Centre for Experimental and Clinical Infection Research; a joint venture between the Medical School Hannover (MHH) and the Helmholtz Centre for Infection Research (HZI), Hannover, Germany.
authors.forename: W H
authors.initials: WH
authors.lastname: Korte
authors.affiliation: Institute of Infection Immunology, TWINCORE, Centre for Experimental and Clinical Infection Research; a joint venture between the Medical School Hannover (MHH) and the Helmholtz Centre for Infection Research (HZI), Hannover, Germany.
authors.forename: N
authors.initials: N
authors.lastname: Goharani
authors.affiliation: Institut Pasteur, Lymphoid Tissue Development Unit, Paris, France.
authors.forename: S
authors.initials: S
authors.lastname: Cording
authors.affiliation: Institut Pasteur, Lymphoid Tissue Development Unit, Paris, France.
authors.forename: G
authors.initials: G
authors.lastname: Eberl
authors.affiliation: Institute of Infection Immunology, TWINCORE, Centre for Experimental and Clinical Infection Research; a joint venture between the Medical School Hannover (MHH) and the Helmholtz Centre for Infection Research (HZI), Hannover, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Sparwasser
authors.affiliation: Institute of Infection Immunology, TWINCORE, Centre for Experimental and Clinical Infection Research; a joint venture between the Medical School Hannover (MHH) and the Helmholtz Centre for Infection Research (HZI), Hannover, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Lochner
mesh_terms: D000818:Animals; D044082:Citrobacter rodentium / Q000276:immunology*; D003106:Colon / Q000276:immunology* / Q000382:microbiology / Q000473:pathology; D004756:Enterobacteriaceae Infections / Q000276:immunology* / Q000473:pathology; D018928:Immunity, Mucosal; D051379:Mice; D050378:T-Lymphocytes, Regulatory / Q000276:immunology* / Q000473:pathology; D058504:Th17 Cells / Q000276:immunology* / Q000473:pathology