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Flagellin hypervariable region determines symbiotic properties of commensal Escherichia coli strains.

ABSTRACT: Escherichia coli represents a classical intestinal gram-negative commensal. Despite this commensalism, different E. coli strains can mediate disparate immunogenic properties in a given host. Symbiotic E. coli strains such as E. coli Nissle 1917 (EcN) are attributed beneficial properties, e.g., promotion of intestinal homeostasis. Therefore, we aimed to identify molecular features derived from symbiotic bacteria that might help to develop innovative therapeutic alternatives for the treatment of intestinal immune disorders. This study was performed using the dextran sodium sulphate (DSS)-induced colitis mouse model, which is routinely used to evaluate potential therapeutics for the treatment of Inflammatory Bowel Diseases (IBDs). We focused on the analysis of flagellin structures of different E. coli strains. EcN flagellin was found to harbor a substantially longer hypervariable region (HVR) compared to other commensal E. coli strains, and this longer HVR mediated symbiotic properties through stronger activation of Toll-like receptor (TLR)5, thereby resulting in interleukin (IL)-22-mediated protection of mice against DSS-induced colitis. Furthermore, using bone-marrow-chimeric mice (BMCM), CD11c+ cells of the colonic lamina propria (LP) were identified as the main mediators of these flagellin-induced symbiotic effects. We propose flagellin from symbiotic E. coli strains as a potential therapeutic to restore intestinal immune homeostasis, e.g., for the treatment of IBD patients.

SUBMITTER: Steimle A

PROVIDER: S-EPMC6597123 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Flagellin hypervariable region determines symbiotic properties of commensal Escherichia coli strains.

Steimle Alex A Menz Sarah S Bender Annika A Ball Brianna B Weber Alexander N R ANR Hagemann Thomas T Lange Anna A Maerz Jan K JK Parusel Raphael R Michaelis Lena L Schäfer Andrea A Yao Hans H Löw Hanna-Christine HC Beier Sina S Tesfazgi Mebrhatu Mehari M Gronbach Kerstin K Wagner Samuel S Voehringer David D Schaller Martin M Fehrenbacher Birgit B Autenrieth Ingo B IB Oelschlaeger Tobias A TA Frick Julia-Stefanie JS

PLoS biology 20190617 6

Escherichia coli represents a classical intestinal gram-negative commensal. Despite this commensalism, different E. coli strains can mediate disparate immunogenic properties in a given host. Symbiotic E. coli strains such as E. coli Nissle 1917 (EcN) are attributed beneficial properties, e.g., promotion of intestinal homeostasis. Therefore, we aimed to identify molecular features derived from symbiotic bacteria that might help to develop innovative therapeutic alternatives for the treatment of i ...[more]

PMID: 31206517

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Flagellin hypervariable region determines symbiotic properties of commensal Escherichia coli strains.

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Flagellin hypervariable region determines symbiotic properties of commensal Escherichia coli strains.

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