Fig. 1

Cell characterization of AMSCs and angiogenic capacity of GDNF-AMSCs in vitro. a Morphology of AMSCs after 3 passages under high magnification. b–d Fluorescence expression of lentiviral vectors with GDNF-transfected AMSCs at 1 day, 3 days, and 5 days. Low GFP expression, indicated by green fluorescence, was detected at 1 day and gradually increased over the course of the transfection. e The cell surface markers of AMSCs were identified by flow cytometry. CD105, CD90, and CD73 were highly expressed in the third generation of AMSC. The expressions of CD34, CD45, and HLA-DR were negative. f, g The tube-like structures were observed using a microscope after 12 h. Representative images and quantification of the organization into capillary-like structures in each group. h Bar graph showing the vasodilation effects after AMSCs and GDNF-transfected AMSC treatments (*P < 0.05, **P < 0.01, ***P < 0.001)