Highlights:
1. Intestinal flora enzymes metabolize small molecules of bile acid.
2. Multiple configurations of bile acids regulate Th17 and Treg cells
and affect the intestinal immunity.
3. Bile acid molecules regulate the intestinal immune microenvironment
by activating or inhibiting FXR and TGR5 in immune and intestinal
epithelial cells.
4. Agonists and antagonists targeting FXR and TGR5 show great promise
for alleviating intestinal inflammation and treating tumors.