IL17A and colitis: Consistent with this, the WT (DSS+Pg+LA) group showed decreased percentages of IL-17+ Th17 cells, higher percentages of Foxp3+ Treg cells, and significantly lower Th17/Treg cell ratios in MLNs and LPLs than the WT (DSS+Pg) group (Fig. 7h–m and Supplementary Fig. 14a–d), further demonstrating that LA supplementation restored the Th17/Treg cell imbalance induced by intragastric Pg gavage in colitis, which also coincided with in vitro experiments showing that LA inhibited the differentiation of Th17 cells and promoted Treg cell differentiation under Th17-polarizing culture conditions.