Accordingly, although administration of MCC950, a specific small-molecule inhibitor of NLRP3 inflammasome activity24, did not affect body weight changes (Fig. 3f), it reduced the severity of colitis in Slco2a1−/− mice (Fig. 3g,h), diminished the Il1b and Tnf mRNA levels (Fig. 3i) with suppressed formation of mature IL-1β and cleaved caspase-1(Fig. 3j, Supplementary Fig. S5), suggesting that the NLRP3 inflammasome contributed to exacerbation of DSS colitis under Slco2a1 deletion. This evidence concerns the gene IL1B and colitis.