title: Characterization of two types of endothelial progenitor cells and their different contributions to neovasculogenesis.
abstract: OBJECTIVE
  Endothelial progenitor cells (EPC) in one study group is not the same as EPC in other investigators, suggesting that EPC is not a single type of cell population. In this study, we tried to demonstrate the heterogeneity of EPC.
  
  
  RESULTS
  We cultured total mononuclear cells from human peripheral blood to get two types of EPC sequentially from the same donors. We called them early EPC and late EPC. Early EPC with spindle shape showed peak growth at 2 to 3 weeks and died at 4 weeks, whereas late EPC with cobblestone shape appeared late at 2 to 3 weeks, showed exponential growth at 4 to 8 weeks, and lived up to 12 weeks. Late EPC was different from early EPC in the expression of VE-cadherin, Flt-1, KDR, and CD45. Late EPC produced more nitric oxide, incorporated more readily into human umbilical vein endothelial cells monolayer, and formed capillary tube better than early EPC. Early EPC secreted angiogenic cytokines (vascular endothelial growth factor, interleukin 8) more so than late EPC during culture in vitro. Both types of EPC showed comparable in vivo vasculogenic capacity.
  
  
  CONCLUSIONS
  We found two types of EPC from a source of adult peripheral blood that might have different roles in neovasculogenesis based on the identified differences.
authors.affiliation: Cardiovascular Laboratory, Clinical Research Institute, Seoul National University Hospital, Korea.
authors.forename: Jin
authors.initials: J
authors.lastname: Hur
authors.forename: Chang-Hwan
authors.initials: CH
authors.lastname: Yoon
authors.forename: Hyo-Soo
authors.initials: HS
authors.lastname: Kim
authors.forename: Jin-Ho
authors.initials: JH
authors.lastname: Choi
authors.forename: Hyun-Jae
authors.initials: HJ
authors.lastname: Kang
authors.forename: Kyung-Kook
authors.initials: KK
authors.lastname: Hwang
authors.forename: Byung-Hee
authors.initials: BH
authors.lastname: Oh
authors.forename: Myoung-Mook
authors.initials: MM
authors.lastname: Lee
authors.forename: Young-Bae
authors.initials: YB
authors.lastname: Park
mesh_terms: D000818:Animals; D002455:Cell Division / Q000502:physiology; D002460:Cell Line; D002470:Cell Survival / Q000502:physiology; D002478:Cells, Cultured; D017077:Culture Media, Conditioned / Q000737:chemistry; D004730:Endothelium, Vascular / Q000166:cytology*; D005260:Female; D005263:Femoral Artery / Q000503:physiopathology / Q000601:surgery; D020869:Gene Expression Profiling / Q000379:methods; D018507:Gene Expression Regulation, Developmental / Q000502:physiology; D006614:Hindlimb / Q000503:physiopathology; D006801:Humans; D016209:Interleukin-8 / Q000378:metabolism; D007511:Ischemia / Q000503:physiopathology; D051379:Mice; D008819:Mice, Nude; D041681:NIH 3T3 Cells / Q000502:physiology; D018919:Neovascularization, Physiologic / Q000502:physiology*; D013234:Stem Cells / Q000737:chemistry* / Q000378:metabolism / Q000502:physiology*; D014471:Umbilical Veins / Q000166:cytology / Q000502:physiology; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
chemical_list: D017077:Culture Media, Conditioned; D016209:Interleukin-8; D042461:Vascular Endothelial Growth Factor A