We found that overexpression of Fgf10 or treatment of recombinant FGF10 (rFGF10) significantly improved the degree of pulmonary fibrosis in bleomycin-injured mice, whether administered simultaneously or at day or day 14 after injury, by promoting the active proliferation of IAAPs [39, 66]. The gene discussed is FGF10; the disease is pulmonary fibrosis.