In line with the results of a previous study, our data revealed a cell-intrinsic role for IL-33 signal in the regulation of MC apoptosis.52 Considering that we did not examine directly whether MC-derived ST2 plays a role, for instance, using mice that are deficient of ST2 only in the MC population, the potential role of other possible confounding factors cannot be completely ruled out during the both the acute and recovery phases of colitis. Here, IL1RL1 is linked to colitis.