In their study, Hams et al.22first reported that deficiency in IL‐25 (i.e., IL‐25−/−) and its receptor IL‐17BR (i.e., IL‐17BR−/−) obviously attenuated local expression of type 2 cytokines (including IL‐4 and IL‐13) and reduced pulmonary collagen deposition in both Schistosoma mansoni egg and bleomycin (BLM)‐induced lung fibrosis model. This evidence concerns the gene IL4 and pulmonary fibrosis.