Effect of Faecalibacterium prausnitzii on Treg Cells and Cytokines in Colitis Mice with LFA-1 Knockout / 胃肠病学

ABSTRACT

It has been widely accepted that Faecalibacterium prausnitzii (Fp) induces the differentiation of Treg cells.Lymphocyte function-associated antigen-1 (LFA-1) is also involved in the differentiation of Treg cells.Aims: To investigate the effect of Fp on Treg cells and cytokines in colitis mice with LFA-1 knockout (LFA-1-/-).Methods: Twenty wild type mice and twenty LFA-1-/-mice with same genetic background were randomly divided into wild type control group, wild type treatment group, LFA-1-/-control group and LFA-1-/-treatment group.Colitis model was induced by drinking DSS solution.Mice in the two treatment groups were intragastrically administrated with Fp.General status and histopathological score were assessed.Percentages of Treg cells in spleen and mesenteric lymph nodes were measured by flow cytometry.Serum levels of IL-10 and TGF-β1 were measured by ELISA.mRNA expressions of IL-10 and TGF-β1 in colonic tissue were detected by real time PCR.Results: Compared with corresponding control groups, histopathological score was significantly decreased in wild type treatment group (P<0.05);percentages of Treg cells in spleen and mesenteric lymph nodes were significantly increased (P<0.05), serum levels of IL-10 and TGF-β1 were significantly increased (P<0.01), expression of TGF-β1 mRNA was significantly increased in wild type treatment group and LFA-1-/-treatment group (P<0.05);expression of IL-10 mRNA was significantly decreased in LFA-1-/-treatment group (P<0.01).Compared with wild type treatment group, serum level of TGF-β1 was significantly decreased (P<0.05), and mRNA expressions of IL-10 and TGF-β1 were significantly decreased in LFA-1-/-treatment group (P<0.05).Conclusions: Fp can up-regulate the percentages of Treg cells and enhance the secretion of anti-inflammatory cytokines IL-10 and TGF-β1 in LFA-1-/-mice.The therapeutic efficacy for colitis in wild type mice is superior to that in LFA-1-/-mice, which may be related to the inhibition of function of Treg cells and secretion of cytokines due to LFA-1 knockout.