Fig. 3

a Curves of animal body weight over time. On day 0, the animals received bleomycin (BLM). The arrowhead indicates the day of iPSC-AEC2 cell transplantation (day 14). Data are means ± SEM of 6 animals per group (*p < 0.05 vs control groups). b Lung weight at the end of the experiment (21 days). iPSC-AEC2 cell transplantation reduced significantly the lung weight compared to the BLM group. Data are means ± SEM of 6 animals per group (*p < 0.05 vs control groups, ^#p < 0.05 vs BLM group). c Lung hydroxyproline (HP) levels at the end of the experiment (21 days). iPSC-AEC2 cell transplantation reduced significantly the total lung content of hydroxyproline compared with the BLM group. Data are means ± SEM of 6 animals per group (*p < 0.05 vs control groups, ^#p < 0.05 vs BLM group). d Representative photographs of lung sections stained with Masson’s trichrome from all the experimental groups. Insets show changes in the multifocal parenchymal lesions in BLM non-transplanted lungs and BLM iPSC-AEC2 transplanted lungs. e Representative photomicrographs of lung sections stained with hematoxylin-eosin; iPSC-AEC2 transplantation in fibrotic animals was able to ameliorate the inflammatory and pulmonary lesions (inset). Magnification × 200. f Representative photomicrographs of lung sections stained with Masson’s trichrome; the presence of interstitial collagen (blue staining, inset) was also diminished in the BLM + iPSC-AEII group. Magnification × 200