title: Vascular gene expression and phenotypic correlation during differentiation of human embryonic stem cells.
abstract: The study of the cascade of events of induction and sequential gene activation that takes place during human embryonic development is hindered by the unavailability of postimplantation embryos at different stages of development. Spontaneous differentiation of human embryonic stem cells (hESCs) can occur by means of the formation of embryoid bodies (EBs), which resemble certain aspects of early embryos to some extent. Embryonic vascular formation, vasculogenesis, is a sequential process that involves complex regulatory cascades. In this study, changes of gene expression along the development of human EBs for 4 weeks were studied by large-scale gene screening. Two main clusters were identified-one of down-regulated genes such as POU5, NANOG, TDGF1/Cripto (TDGF, teratocarcinoma-derived growth factor-1), LIN28, CD24, TERF1 (telomeric repeat binding factor-1), LEFTB (left-right determination, factor B), and a second of up-regulated genes such as TWIST, WNT5A, WT1, AFP, ALB, NCAM1. Focusing on the vascular system development, genes known to be involved in vasculogenesis and angiogenesis were explored. Up-regulated genes include vasculogenic growth factors such as VEGFA, VEGFC, FIGF (VEGFD), ANG1, ANG2, TGFbeta3, and PDGFB, as well as the related receptors FLT1, FLT4, PDGFRB, TGFbetaR2, and TGFbetaR3, other markers such as CD34, VCAM1, PECAM1, VE-CAD, and transcription factors TAL1, GATA2, and GATA3. The reproducibility of the array data was verified independently and illustrated that many genes known to be involved in vascular development are activated during the differentiation of hESCs in culture. Hence, the analysis of the vascular system can be extended to other differentiation pathways, allocating human EBs as an in vitro model to study early human development.
authors.affiliation: Department of Obstetrics and Gynecology, Rambam Medical Center, Haifa 31096, Israel.
authors.forename: Sharon
authors.initials: S
authors.lastname: Gerecht-Nir
authors.forename: Jean-Eudes
authors.initials: JE
authors.lastname: Dazard
authors.forename: Michal
authors.initials: M
authors.lastname: Golan-Mashiach
authors.forename: Sivan
authors.initials: S
authors.lastname: Osenberg
authors.forename: Alex
authors.initials: A
authors.lastname: Botvinnik
authors.forename: Ninette
authors.initials: N
authors.lastname: Amariglio
authors.forename: Eytan
authors.initials: E
authors.lastname: Domany
authors.forename: Gideon
authors.initials: G
authors.lastname: Rechavi
authors.forename: David
authors.initials: D
authors.lastname: Givol
authors.forename: Joseph
authors.initials: J
authors.lastname: Itskovitz-Eldor
mesh_terms: D018952:Antigens, CD34 / Q000096:biosynthesis; D001808:Blood Vessels / Q000196:embryology*; D002454:Cell Differentiation; D016000:Cluster Analysis; D019295:Computational Biology; D004622:Embryo, Mammalian / Q000166:cytology*; D047108:Embryonic Development; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D015151:Immunoblotting; D007150:Immunohistochemistry; D018613:Microscopy, Confocal; D009130:Muscle, Smooth / Q000166:cytology; D009389:Neovascularization, Pathologic; D020411:Oligonucleotide Array Sequence Analysis; D010641:Phenotype; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013234:Stem Cells / Q000166:cytology*; D013997:Time Factors; D015533:Transcriptional Activation; D015854:Up-Regulation
chemical_list: D018952:Antigens, CD34