Although the role of FKN in the pathogenesis of lung fibrosis is unclear, a study in mice model revealed that bleomycin (BLC)‐induced lung fibrosis is associated with upregulation of CX3CR1 on fibroblasts and M2‐type macrophages, which play a critical role in fibrosis.77 This evidence concerns the gene CX3CR1 and pulmonary fibrosis.