OTUB2 and colitis: Given that (i) OTUB2 was highly expressed in macrophages in the colon, (ii) OTUB2 in haematopoietic cells played a predominant role in colitis, and (iii) OTUB2 enhanced MDP‐induced cytokine production in macrophages, we concluded that OTUB2 exerted its function in intestinal inflammation by regulating macrophages.