Abstract 609: Comparing the Pro-angiogenic Properties of Induced Endothelial Cells and Induced Pluripotent Stem Cell Derived Endothelial Cells in a Murine Hindlimb Ischaemia Model
Introduction: Endothelial cells derived from induced pluripotent stem cells (iPSC-ECs) have been shown to promote angiogenesis in vivo. Recently, an easier and more effective method of generating endothelial cells has been developed, by directly differentiating fibroblasts into endothelial cells (iECs), bypassing the pluripotent intermediate. However, the pro-angiogenic properties of iECs have not yet been determined. Accordingly, we compared survival, engraftment and pro-angiogenic potential of iECs versus iPSC-ECs in a mouse model of hindlimb ischaemia.
Methods and Results: Human iPSC-ECs and iECs were transduced with firefly luciferase and green fluorescent protein reporter for bioluminescence imaging. They exhibited endothelial behavior in vitro, assessed by migration towards VEGF, uptake of acetylated-LDL and tubule formation on matrigel. NOD-SCID mice (n=7-9) underwent unilateral femoral artery ligation and received either control vehicle or 1x106 iPSC-ECs or iECs, via intramuscular injection. Recovery of the ischaemic limb was tracked for 14 days. Laser Doppler imaging after femoral artery ligation revealed enhanced blood perfusion recovery in the iEC group vs. control at day 7 (p<0.05), 10 and 14 (p<0.001). IPSC-ECs enhanced recovery vs. control at day 14 (p<0.05). At day 10, perfusion was significantly greater in iEC vs. iPSC-EC treated mice (p<0.01). IPSC-EC and iEC bioluminescent signals decreased over 14 days, but remained above background at all observed time-points (p<0.0001). Extrapolation of the model suggested persistence of signal until day 21. Analysis of hindlimb skeletal muscle demonstrated significantly greater capillary density in the ischemic limb of mice treated with iECs, vs. control (179±11 vs. 125±10 capillaries/image; p<0.05).
Conclusion: iECs have striking in vivo pro-angiogenic effects and appear to be more potent than iPSC-ECs. These findings support further development of iECs for therapeutic angiogenesis.
Author Disclosures: Z.E. Clayton: None. S.G. Yuen: None. S. Sadeghipour: None. J.D. Hywood: None. S. Abraham: None. W.J. Wong: None. J.P. Cooke: None. S. Patel: None.
- © 2015 by American Heart Association, Inc.