title: [Differentiation of human embryonic stem cells to endothelial cells via improved three-dimension approach].
abstract: OBJECTIVE
  To establish an improved three-dimension (3D) and serum-free approach to differentiate human embryonic stem cells (hESCs) into endothelial cells, and detect the endothelial functions of the obtained cells.
  
  
  METHODS
  We cultured undifferentiated H9 human embryonic stem cell line in low-adhesion dishes to form embryonic bodies (EBs). After 12 days, EBs were harvested, re-suspended into rat tail collagen type I, and put into the incubator (37℃). After 30 minutes, EGM-2 culture medium was added to the solidified collagen, and the EBs were cultured for another 3 days to form embryonic body-sproutings (EB-sproutings). EB-sproutings were digested with 0.25% collagenase I and 0.56 U/ml Liberase Blendzyme for 20 minutes respectively, and the CD31(+) cells were sorted by FACS. The endothelial functions were tested by Dil-ac-LDL uptake assay and tube formation assay.
  
  
  RESULTS
  This approach raised the efficiency of endothelial differentiation to 18%, and also avoided the contamination with animal materials. The obtained hESC-derived endothelial cells (hESC-ECs) had the similar pattern of surface biomarkers as human umbilical vein endothelial cells (HUVECs), and their endothelial functions were confirmed by the uptake of Dil-ac-LDL and the tube formation on Matrigel.
  
  
  CONCLUSIONS
  The improved 3D approach can enhance the efficiency of differentiation from hESCs into endothelial cells. Furthermore, serum free differentiation system may be applied in future hESC-based therapies for various ischemic diseases.
authors.affiliation: Department of Pathology, Nankai University School of Medicine, Tianjin, China.
authors.forename: Wei-jun
authors.initials: WJ
authors.lastname: Su
authors.forename: Bao-yu
authors.initials: BY
authors.lastname: Wang
authors.forename: Xiang-he
authors.initials: XH
authors.lastname: Song
authors.forename: Li-na
authors.initials: LN
authors.lastname: Wang
authors.forename: Yan-hua
authors.initials: YH
authors.lastname: Liu
authors.forename: Man-qian
authors.initials: MQ
authors.lastname: Zhou
authors.forename: Ling-ling
authors.initials: LL
authors.lastname: Tong
authors.forename: Zong-jin
authors.initials: ZJ
authors.lastname: Li
mesh_terms: D018929:Cell Culture Techniques / Q000379:methods*; D002454:Cell Differentiation; D002460:Cell Line; D024042:Collagen Type I; D003470:Culture Media; D053595:Embryonic Stem Cells / Q000166:cytology*; D042783:Endothelial Cells / Q000166:cytology*; D006801:Humans
chemical_list: D024042:Collagen Type I; D003470:Culture Media