Fig. 4

The effect of overexpressing p130 or E2F4 on the differentiation of mMSCs into AT II in vivo. a Representative immunofluorescent staining images of the injured lungs from mice at 7 and 14 days after mMSC administration. mMSC engraftment in the lung tissues (GFP-positive cells) appears green, the specific marker of AT II (SP-C) appears red and the nuclei of cells that were stained with DAPI appear blue. Double-stained cells with both GFP and DAPI appear light green. The co-localization of green, red and blue appears white. Representative photographs are shown from three mouse lungs at 7 and 14 days after mMSC administration. All microphotographs were acquired at × 200 magnification (scale bar = 50 μm). b Fluorescent counts in the injured lungs from mice at 7 and 14 days after mMSC administration. Overlapping fluorescence of DAPI, GFP and SP-C was counted in randomly selected fields (count/field) (n = 3; *p < 0.05 compared with the LPS+MSC-NC group). c The protein expression of SP-A and SP-C in the lung tissue at 7 and 14 days after mMSC administration was evaluated by western blot analysis (n = 3, *p < 0.05 compared with the control group; #p < 0.05 compared with the ARDS group; δp < 0.05 compared with the LPS+MSC-NC group). ARDS acute respiratory distress syndrome, AT II type II alveolar epithelial cells, mMSCs mouse mesenchymal stem cells, GFP green fluorescent protein, SP-A surfactant protein A, SP-C surfactant protein C