Endothelial Differentiation of Human Embryonic Stem Cell and Functional Blood Vessels Formation in Vivo

Background: Human embryonic stem (hES) cells are distinguished by their capacity for self-renewal and pluripotency. Here we characterize the differentiation of hES cell-derived endothelial cells (hESC-ECs), use molecular imaging techniques to examine their survival and function in vivo.

Methods and Results: Here we introduced two-step procedures to increase endothelial differentiation efficiency of hESCs by subcultured embryoid bodies (EBs) in collagen. Single cell suspensions from EBs sprouting in collagen were obtained by treatment with collagenase and Liberase Blendzyme IV and CD31/CD144 positive cells were isolated by FACScan. After isolation, these hESC-ECs express endothelial cell markers similar to HUVEC, form vascular-like channels, and incorporate DiI-labeled acetylated low-density lipoprotein (DiI-Ac-LDL) in vitro. Real time PCR array described increasing endothelial transcription. Using whole genome microarrays, we investigated the hESCs derived endothelial cells (hESC-ECs) transcriptome that occur among sequenced hESCs differentiation processes and human umbilical vein endothelial cells (HUVECs). We found that hESC-ECs expressed endothelial gene at pattern similar to HUVECs. By intravital microscope, we demonstrated that hESC-ECs can form function vessels with blood flow.

Conclusion: Taken together, two-steps procedures increased the endothelial differentiation efficiency hESCs, and hESC-ECs can form functional vessel in vivo.