Published online Jun 7, 2021. doi: 10.3748/wjg.v27.i21.2834
Peer-review started: January 23, 2021
First decision: February 10, 2021
Revised: March 30, 2021
Accepted: April 28, 2021
Article in press: April 28, 2021
Published online: June 7, 2021
Ulcerative colitis (UC) is a growing global disease in which gut microbiota dysbiosis plays an important pathogenic role. However, the current drugs for UC treatment are far from optimal. Therefore, alternative safe and effective new treatments need to be developed.
Clinical practice has confirmed the therapeutic value of fecal microbiota transplanta
The aim of the study was to explore the effect and mechanism of FMT on regulating the balance of gut microbiota and anti-inflammation in dextran sulfate sodium (DSS)-induced colitis.
Experimental colitis was induced by DSS, then the severity of intestinal inflammation was evaluated by body weight, colon length, disease activity index and histological scores. Gut microbiota alteration was analyzed through 16S rRNA sequencing. Transcriptome sequencing was used to screen differentially expressed genes in colon. The frequency of immune cells in lamina propria were phenotyped by flow cytometry.
DSS-induced weight loss, colon length shortening, disease activity index score and histological score were significantly alleviated after FMT treatment. 16S rRNA sequencing indicated that FMT up-regulated the relative abundance of Lactobacillus and down-regulated the relative abundance of Clostridium_sensu_stricto_1 and Turicibacter. Transcriptomics-based differential gene analysis showed that FMT could regulate colonic T cell function. Further flow cytometry analysis showed that FMT downregulated the number of colonic CD4+ and CD8+ T cells to maintain intestinal homeostasis. Moreover, we found that the abundance of Clostridium_sensu_stricto_1 was positively correlated with the expression of inflammation-related genes such as REG3G, CCL8 and IDO1.
FMT alleviated DSS-induced colitis in mice by improving the gut microbiota and regulating T-cell function.
This study has initially revealed the mechanism of FMT in the treatment of colitis, which will be confirmed by human studies in the future.