Irradiated Human Umbilical Vein Endothelial Cells Undergo Endothelial-Mesenchymal Transition via the Snail/miR-199a-5p Axis to Promote the Differentiation of Fibroblasts into Myofibroblasts

Figure 1

Irradiated HUVECs promote the expression of MRC-5 fibrotic markers. Panel (a): scheme illustrating the procedure to evaluate the contribution of HUVECs to MRC-5 fibrotic markers. MRC-5 cells were cocultured with irradiated HUVECs with no physical contact (noncontact). MRC-5 cells were cocultured with irradiated HUVECs with physical contact (contact). Panel (b): HUVECs were preincubated in the presence or absence of irradiation and then coincubated with MRC-5 cells (noncontact). After incubation for 24 or 48 h, the MRC-5 cells were harvested. Total protein was extracted. Western blot shows the protein expression of collagen I and α-SMA. Panel (c): cell sorting by flow cytometry. MRC-5 cells were labeled with fluorescent GFP (green cells) and plated with unlabeled HUVECs at a ratio of 9 : 1. Panel (d): HUVECs were preincubated in the presence or absence of radiation and then coincubated with MRC-5 cells (contact). After incubation for 24 or 48 h, the MRC-5 cells were sorted by flow cytometry and harvested. Western blot was performed to examine total protein. Panel (e): dual immunofluorescence analysis of α-SMA and stress fibers stained with phalloidin green. Colocalization of stress fibers and α-SMA in MRC-5 was evident under treatment of irradiated HUVECs.

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