In contrast to the beneficial effects of the IL-33/ILC2 axis in glomerulosclerosis, a potential deleterious role of endogenous IL-33 in kidney fibrosis was reported by Chen et al., demonstrating partial protection from tubulointerstitial fibrosis induced by unilateral urinary obstruction (UUO) in Il33−/− and Il1rl1−/− mice (41). Here, IL33 is linked to glomerulosclerosis.