USP38 and colitis: Interestingly, we found that although the difference of colon length between KO>KO and KO>WT is smaller than that between KO>WT and WT>WT, the colon of KO>KO still had shorter length than KO>WT, indicating that despite its major role in the bone marrow‐derived cells, USP38 might also function in other structural cell types, which contribute to the colitis progressing.