Abstract：
Objective To isolate and culture endothelial progenitor cells (EPCs) from human fetal aorta, to analyze the capability of EPCs differentiating into endothelial cells, and evaluate the feasibility of using human fetal aorta-derived EPCs for clinical application of stem cell technology.
Methods EPCs were isolated from clinical aborted fetal aorta by digesting aorta with type I collagenase, and proliferated in DMEM/F12 medium supplemented with LIF, bFGF, EGF, ECGS and low serum. The expression of CD133, CD34 and VEGFR2 of EPCs was assessed by RT-PCR, immuno?uorescence staining and FACS analysis. EPCs were induced to differentiate into endothelial cells by cultured with medium containing 20% FCS and VEGF, and the differentiation ability was analyzed.
Results EPCs derived from human fetal aorta expressed CD133, CD34 and VEGFR2. The EPCs proliferated rapidly in vitro in DMEM/F12 containing LIF, bFGF, EGF and ECGS, and possessed the ability of DiI-Ac-LDL uptake and tube formation on matrigel. After induction by VEGF in cultured EPCs, expression of CD133 was decreased significantly; and expression level of vWF, CD31 and ELAM-1 was increased. Moreover, EPCs’ ability of tube formation and uptake of DiI-Ac-LDL was increased upon VEGF induction. All of these alteration indicated that EPCs had differentiated into endothelial cells.
Conclusion EPCs derived from early fetal aorta possess strong self-renewal capability and the potential of differentiating into endothelial cells, indicating these cells could be used for clinical EPCs treatment.
2012, Vol. 7 
