HIF1A and colitis: However, we found that Hif1a−/− tTregs retained the ability to inhibit colitis (Supplementary Fig. 13), in contrast to the impaired suppressive function of Hif1a−/− tTregs in the same model reported by Clambey et al.55 We noticed that Hif1a−/− tTregs were less effective than WT tTregs in the readout of colitis score (Fig. 6f), but not in the histology analysis (Supplementary Fig. 13).