Gut commensal Lactobacillus reuteri 100-23 stimulates an immunoregulatory response.
Lactobacillus reuteri 100-23 is a bacterial commensal of the gastrointestinal tract of mice. Previous studies have shown that colonization of the murine gut by this strain stimulates small-bowel enterocytes to produce proinflammatory cytokines. This is associated with a mild, transitory inflammatory response 6 days after inoculation of formerly Lactobacillus-free animals. The inflammation subsides by 21 days after colonization, although lactobacilli continue to be present in the bowel. To determine the immunological mechanisms that underpin tolerance to bowel commensals, we investigated cytokine responses of dendritic cells and T cells after exposure to cells of L. reuteri 100-23. Interleukin-10 (IL-10), IL-2 and transforming growth factor-beta (TGF-beta) concentrations in supernatants of cultured immune cells, as well as the results of proliferative assays of mesenteric lymph node (MLN) cells and quantification of Foxp3-positive cells in MLN and spleen, indicated that L. reuteri 100-23 stimulated the development of an increased number of regulatory T cells.
Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand.
Megan
M
Livingston
Diane
D
Loach
Michelle
M
Wilson
Gerald W
GW
Tannock
Margaret
M
Baird
D000818:Animals; D002454:Cell Differentiation; D018920:Coculture Techniques; D005260:Female; D007108:Immune Tolerance; D007422:Intestines / Q000276:immunology* / Q000382:microbiology*; D052200:Limosilactobacillus reuteri / Q000276:immunology*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology