title: Reversal of endothelial progenitor cell dysfunction in patients with type 2 diabetes using a conditioned medium of human embryonic stem cell-derived endothelial cells.
abstract: BACKGROUND
  The potential clinical application of bone marrow or peripheral blood-derived progenitor cells for cardiovascular regeneration in patients with diabetes mellitus (DM) is limited by their functional impairment. We sought to determine the mechanisms of impaired therapeutic efficacy of peripheral blood-derived progenitor cells in type 2 DM patients and evaluated the use of cell-free conditioned medium obtained from human embryonic stem cell-derived endothelial-like cells (ESC-ECs) to reverse their functional impairment.
  
  
  METHODS
  The angiogenic potential of late outgrowth endothelial cells (OECs) and cytokine profile of the conditional medium of proangiogenic cells (PACs) derived from peripheral blood-mononuclear cells of healthy control and DM patients and ESC-ECs was compared by in vitro tube formation assay and a multiplex bead-based immunoassay kit, respectively. The in vivo angiogenic potential of ESC-ECs derived conditioned medium in rescuing the functional impairment of PB-PACs in DM patients was investigated using a hindlimb ischemia model.
  
  
  RESULTS
  Human ESC-ECs had similar functional and phenotypic characteristics as OECs in healthy controls. Cytokine profiling showed that vascular endothelial growth factor, stromal cell-derived factor 1 and placental growth factor were down-regulated in PACs from DM patients. Tube formation assay that revealed functional impairment of OECs from DM patients could be rescued by ESC-ECs conditioned medium. Administration of ESC-ECs conditioned medium restored the therapeutic efficacy of PB-PACs from DM patients in a mouse model of hindlimb ischemia.
  
  
  CONCLUSIONS
  Our results showed that peripheral blood-derived progenitor cells from DM patients have impaired function because of defective secretion of angiogenic cytokines, which could be restored by supplementation of ESC-ECs conditioned medium.
authors.affiliation: Cardiology Division, Department of Medicine, The University of Hong Kong, Hong Kong, HKSAR, China.
authors.forename: Jenny C Y
authors.initials: JC
authors.lastname: Ho
authors.forename: Wing-Hon
authors.initials: WH
authors.lastname: Lai
authors.forename: Ming-Fang
authors.initials: MF
authors.lastname: Li
authors.forename: Ka-Wing
authors.initials: KW
authors.lastname: Au
authors.forename: Mei-Chu
authors.initials: MC
authors.lastname: Yip
authors.forename: Navy L Y
authors.initials: NL
authors.lastname: Wong
authors.forename: Ethel S K
authors.initials: ES
authors.lastname: Ng
authors.forename: Francis F Y
authors.initials: FF
authors.lastname: Lam
authors.forename: Chung-Wah
authors.initials: CW
authors.lastname: Siu
authors.forename: Hung-Fat
authors.initials: HF
authors.lastname: Tse
mesh_terms: D000818:Animals; D015153:Blotting, Western; D016022:Case-Control Studies; D002454:Cell Differentiation; D002478:Cells, Cultured; D054377:Chemokine CXCL12 / Q000235:genetics / Q000378:metabolism; D017077:Culture Media, Conditioned / Q000494:pharmacology*; D016207:Cytokines / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology*; D053595:Embryonic Stem Cells / Q000166:cytology / Q000378:metabolism*; D042783:Endothelial Cells / Q000166:cytology / Q000378:metabolism*; D006614:Hindlimb / Q000098:blood supply* / Q000503:physiopathology; D006801:Humans; D007124:Immunoenzyme Techniques; D007511:Ischemia / Q000503:physiopathology; D008297:Male; D051379:Mice; D016513:Mice, SCID; D008875:Middle Aged; D009389:Neovascularization, Pathologic / Q000517:prevention & control*; D000072483:Placenta Growth Factor; D011257:Pregnancy Proteins / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism*; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism
chemical_list: D054377:Chemokine CXCL12; D017077:Culture Media, Conditioned; D016207:Cytokines; C000608036:PGF protein, human; C000608037:Pgf protein, mouse; D011257:Pregnancy Proteins; D012333:RNA, Messenger; D042461:Vascular Endothelial Growth Factor A; D000072483:Placenta Growth Factor