title: Circulating endothelial progenitor cells and coronary collaterals in patients with non-ST segment elevation myocardial infarction.
abstract: BACKGROUND
  Endothelial progenitor cells (EPCs) are bone marrow-derived cells that are augmented in response to ischemia and incorporated into neovascularization sites. We sought to determine whether circulating EPCs are related to collateral formation following non-ST segment elevation myocardial infarction (NSTEMI).
  
  
  METHODS
  Twenty patients who underwent percutaneous coronary intervention (PCI) within a week of NSTEMI were divided into two groups: patients without collaterals (coll-, n=10) and patients with Rentrop grade 3--4 collaterals (coll+, n=10). Blood samples were drawn before PCI and 24+/- 2 h after PCI. EPC colonies were grown from peripheral blood mononuclear cells, characterized, and counted. Using flow cytometry the percentage of cells co expressing vascular endothelial growth factor receptor-2 and CD 133 was determined.
  
  
  RESULTS
  The coll+ group had higher degree of culprit vessel stenosis and lower initial thrombolysis in myocardial infarction flow grade. The relative number of EPCs before PCI was significantly higher in the coll+ group than in the coll- group (1.49 +/- 0.9% vs. 0.77+/- 0.4%, p= 0.045). There were no significant intergroup differences in the number of EPC colony-forming cells. The number of EPC colonies increased in the coll- group after PCI (9.5 +/- 4.8 to 14.0 +/- 5.9/10(6) cells, p=0.01).
  
  
  CONCLUSIONS
  This study supports an association between circulating EPC levels and collateral formation in patients with an NSTEMI.
authors.affiliation: The Methodist DeBakey Heart Center and Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: Eli I
authors.initials: EI
authors.lastname: Lev
authors.forename: Neal S
authors.initials: NS
authors.lastname: Kleiman
authors.forename: Yochai
authors.initials: Y
authors.lastname: Birnbaum
authors.forename: David
authors.initials: D
authors.lastname: Harris
authors.forename: Martin
authors.initials: M
authors.lastname: Korbling
authors.forename: Zeev
authors.initials: Z
authors.lastname: Estrov
mesh_terms: D000071916:AC133 Antigen; D000368:Aged; D015703:Antigens, CD / Q000378:metabolism; D015415:Biomarkers; D002452:Cell Count; D003097:Collateral Circulation / Q000502:physiology*; D003326:Coronary Circulation / Q000502:physiology*; D005260:Female; D006023:Glycoproteins / Q000378:metabolism; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000473:pathology* / Q000503:physiopathology*; D010455:Peptides / Q000378:metabolism; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000378:metabolism
chemical_list: D000071916:AC133 Antigen; D015703:Antigens, CD; D015415:Biomarkers; D006023:Glycoproteins; D010455:Peptides; D040301:Vascular Endothelial Growth Factor Receptor-2