Fig. 4

hucMSC-Exos inhibited pulmonary fibrosis in mice (n = 3). a The experimental process of mice instilled with silica and following hucMSC-Exo treatment. b H&E and Masson staining in the lungs of mice in each group at 15 and 30 days (light micrograph magnifications of × 10 and × 200); yellow arrows show typical Masson-positive collagenous fibers. c The percentage of Masson staining-positive collagenous fiber was significantly increased in the silica group but decreased in the silica + hucMSC-Exo group at 15 and 30 days mice. d The content of HYP was significantly increased in the silica group but decreased in the silica + hucMSC-Exos at different times. The data are presented as means ± SD (n = 3). *P < 0.05 compared with the control group. e–j The expression of collagen deposition marker of COL1A1 and FN was detected by Western blotting and qPCR in mice at each group. *P < 0.05 compared with the control group, ^#P < 0.05 compared with the silica group