Fig. 2

Inhibition of macrophage infiltration inhibits the development of pulmonary fibrosis in bleomycin-treated mice. a Mice (n = 10 in each group) received either saline or bleomycin (5 mg/kg body weight) intratracheally. Mice were sacrificed 21 days later. The expression of F4/80 in lung tissues was measured by immunofluorescence assay. Representative images are shown. b Expression of F4/80 mRNA in lung tissues was measured by q-PCR. Results are expressed as means ± SD (n = 5; *p < 0.05 vs. Saline). c A myeloid-specific ablating liposome, clodronate, was injected intratracheally every three days starting two days before the injection of bleomycin, and control mice received injections of a control liposome (n = 10). d The expression of F4/80 in lung tissues was examined by immunohistochemistry (left panels) and the infiltration of macrophages was analyzed by flow cytometric analysis (right panels). e Pulmonary fibrosis was determined by hematoxylin-eosin (H&E) staining and collagen I was revealed by Masson’s trichrome staining. Representative micrographs of histology are shown. f The protein levels of α-smooth muscle actin (α-SMA) and collagen I in lung tissues was measured by western blotting. g The expression of α-SMA and collagen I in lung tissues was measured by immunofluorescence assay