title: Endothelial progenitor cells and colony-forming units in rheumatoid arthritis: association with clinical characteristics.
abstract: OBJECTIVE
  To compare levels of a range of endothelial progenitor cells (EPCs) and endothelial colony-forming units (CFUs) in control participants and RA patients, in addition to verifying whether levels of EPCs or CFUs are associated with clinical characteristics in RA patients.
  
  
  METHODS
  Peripheral blood mononuclear cells (PBMCs) from 36 RA patients and 30 control participants were analysed by flow cytometry for EPCs defined by the expression of CD34/CD133, CD34/CD117, CD34/CD31, CD34/KDR and CD34/CD133/KDR. Endothelial cell colonies derived from culture of PBMCs were also assessed by CFU assay.
  
  
  RESULTS
  No differences in levels of EPCs were observed in RA patients compared with controls. However, levels of EPCs were negatively associated with prognostic markers of poor disease status, but not cardiovascular (CV)-related risk factors. Furthermore, the majority of EPCs examined were negatively correlated with levels of RF. In contrast, CFU number was significantly reduced in RA patients compared with controls and was negatively associated with CV risk factors only.
  
  
  CONCLUSIONS
  These findings indicate that more informative than comparing changes in absolute levels of EPCs, the examination of their relationship with clinical characteristics of RA patients can reveal significant associations, which may provide important clinical insights.
authors.affiliation: Molecular Medicine Section, Department of Neuroscience, University of Siena, Siena, Italy.
authors.forename: C G
authors.initials: CG
authors.lastname: Egan
authors.forename: F
authors.initials: F
authors.lastname: Caporali
authors.forename: E
authors.initials: E
authors.lastname: Garcia-Gonzalez
authors.forename: M
authors.initials: M
authors.lastname: Galeazzi
authors.forename: V
authors.initials: V
authors.lastname: Sorrentino
mesh_terms: D000368:Aged; D001172:Arthritis, Rheumatoid / Q000097:blood*; D001799:Blood Sedimentation; D002318:Cardiovascular Diseases / Q000209:etiology; D002478:Cells, Cultured; D003114:Colony-Forming Units Assay; D042783:Endothelial Cells / Q000473:pathology; D004730:Endothelium, Vascular / Q000473:pathology; D005260:Female; D006412:Hematopoietic Stem Cells / Q000473:pathology*; D006801:Humans; D018655:Lymphocyte Count; D008297:Male; D011379:Prognosis; D012217:Rheumatoid Factor / Q000097:blood; D012307:Risk Factors; D012720:Severity of Illness Index
chemical_list: D012217:Rheumatoid Factor