title: Predictors of low circulating endothelial progenitor cell numbers in haemodialysis patients.
abstract: BACKGROUND
  End-stage renal disease (ESRD) patients exhibit increased cardiovascular mortality associated with cardiovascular calcifications and endothelial dysfunction. As circulating endothelial progenitor cells (EPCs) harbour vascular regenerative potential and are altered in uraemia, we examined clinical and biochemical factors influencing EPC levels as well as the relation between EPC numbers and function and uraemic cardiovascular calcifications.
  
  
  METHODS
  Sixty-five haemodialysis patients were investigated. Cardiovascular calcifications were assessed by multi-slice spiral CT (MSCT, n = 44) with the calculation of coronary Agatston scores and indirectly by carotid-femoral pulse wave velocity (PWV, n = 61). EPCs were quantified in peripheral blood (CD34(+)/KDR(+)) and at day 7 after ex vivo cultivation (ac-LDL(+)/lectin(+)) by flow cytometry. In addition, colony-forming units (CFUs), migratory activity, adhesion and viability of isolated EPCs were analysed.
  
  
  RESULTS
  EPC numbers were reduced (P < 0.001) compared to 27 healthy controls (-64%) or 81 patients with documented coronary artery disease and normal renal function (-58%). Coronary calcifications did not exhibit a significant association with the numbers of circulating CD34(+)/KDR(+) or isolated ac-LDL(+)/lectin(+) EPCs. No difference in EPC functions was observed between the 10 patients with the lowest Agatston scores (range 0-41) versus those with the highest scores (range 1181-3736). Multivariate analysis revealed low fetuin-A serum levels to be a positive predictor, while haematocrit and reticulocytes were negative predictors of reduced ac-LDL(+)/lectin(+) EPC numbers.
  
  
  CONCLUSIONS
  EPC numbers and function did not correlate with the degree of coronary calcifications in haemodialysis patients. Rather they appear to be related to serum fetuin-A levels, haematocrit and reticulocytes.
authors: Department of Nephrology and Clinical Immunology, RWTH University Hospital Aachen, Pauwelsstr. 30, 52074 Aachen, Germany. gschlieper@ukaachen.de
authors: Georg
authors: G
authors: Schlieper
authors: Mihail
authors: M
authors: Hristov
authors: Vincent
authors: V
authors: Brandenburg
authors: Thilo
authors: T
authors: Krüger
authors: Ralf
authors: R
authors: Westenfeld
authors: Andreas H
authors: AH
authors: Mahnken
authors: Eray
authors: E
authors: Yagmur
authors: Georg
authors: G
authors: Boecker
authors: Nicole
authors: N
authors: Heussen
authors: Ulrich
authors: U
authors: Gladziwa
authors: Markus
authors: M
authors: Ketteler
authors: Christian
authors: C
authors: Weber
authors: Jürgen
authors: J
authors: Floege
mesh_terms: D053687:Adult Stem Cells / Q000473:pathology*; D000368:Aged; D001772:Blood Cell Count; D001798:Blood Proteins / Q000378:metabolism; D002114:Calcinosis / Q000209:etiology; D016022:Case-Control Studies; D002448:Cell Adhesion; D002465:Cell Movement; D002470:Cell Survival; D003324:Coronary Artery Disease / Q000097:blood / Q000209:etiology; D042783:Endothelial Cells / Q000473:pathology*; D005260:Female; D006400:Hematocrit; D006801:Humans; D066298:In Vitro Techniques; D007676:Kidney Failure, Chronic / Q000097:blood / Q000150:complications / Q000628:therapy; D008297:Male; D008875:Middle Aged; D006435:Renal Dialysis; D012156:Reticulocytes / Q000473:pathology; D012307:Risk Factors; D060749:alpha-2-HS-Glycoprotein
chemical_list: C556354:AHSG protein, human; D001798:Blood Proteins; D060749:alpha-2-HS-Glycoprotein