Studies confirmed (44) that the neutrophil inhibitor civirolox sodium reduces the degree of pulmonary fibrosis by inhibiting TGF-β expression; In addition, Gregory et al. (45) used bleomycin to induce fibrosis in mice, and found that fibroblasts and myofibroblasts in mice with NE(-/-) were greatly reduced, and the degree of pulmonary fibrosis was less than in the normal group, further confirming that neutrophils are participated in the immune adjustment of IPF. This evidence concerns the gene TGFB1 and fibrosis.