title: Tissue factor up-regulation in proinflammatory conditions confers thrombin generation capacity to endothelial colony-forming cells without influencing non-coagulant properties in vitro.
abstract: BACKGROUND
  Endothelial progenitor cells (EPC) are good candidates for cell-based therapy in cardiovascular diseases. However, concerns have been raised about the potential risks of EPC-based cell therapy, in terms of thrombogenicity particularly in inflammatory conditions, currently observed in such patients. Tissue factor (TF) can trigger coagulation and may support thrombogenicity. TF is also a key receptor in angiogenesis.
  
  
  OBJECTIVE
  The present study was designed to (i) evaluate the capacity of resting and tumour necrosis factor-alpha (TNF)-α-stimulated late-outgrowth endothelial colony-forming cells (ECFCs) to express TF and (ii) investigate the effect of TF/FVII(a) interaction on procoagulant and non-procoagulant activities of ECFCs in vitro.
  
  
  METHODS
  ECFCs from cord blood (cb) and adult peripheral blood (ab) were analyzed for TF expression and activity using reverse transcription-polymerase chain reaction (RT-PCR), flow cytometry, Western blot and a thrombin generation assay. Non-procoagulant properties of TF-expressing ECFCs were investigated in vitro using wound-healing, cell proliferation, tube formation and spheroid-based assays.
  
  
  RESULTS
  ECFCs expressed TF in response to TNF-α. The up-regulation of TF conferred to ECFCs a FVII(a)-dependent thrombin generation activity. Compared with cb-ECFC, ab-ECFCs can display a higher level of constitutive TF expression and activity, with a notable heterogeneity among donors. TF/FVIIa interaction did not modify non-procoagulant properties of TNF-α stimulated cb-ECFCs in vitro.
  
  
  CONCLUSIONS
  Proinflammatory conditions up-regulate TF expression in ECFCs. This expression confers to ECFCs a strong thrombin generation capacity without influencing their non-coagulant properties. Our results suggest that EPC-based cell therapy may be associated with prothrombotic risk which could be limited by inhibiting TF without affecting the proangiogenic capacity of the cells.
authors.affiliation: Laboratoire d'Hématologie, CHU Robert Debré and EA-3801, Faculté de Médecine, IFR-53 Interactions Cellules MicroEnvironnement, Université de Reims Champagne-Ardenne, Reims, France.
authors.forename: W
authors.initials: W
authors.lastname: Cuccuini
authors.forename: S
authors.initials: S
authors.lastname: Poitevin
authors.forename: G
authors.initials: G
authors.lastname: Poitevin
authors.forename: F
authors.initials: F
authors.lastname: Dignat-George
authors.forename: P
authors.initials: P
authors.lastname: Cornillet-Lefebvre
authors.forename: F
authors.initials: F
authors.lastname: Sabatier
authors.forename: P
authors.initials: P
authors.lastname: Nguyen
mesh_terms: D015153:Blotting, Western; D049109:Cell Proliferation; D003029:Coagulants / Q000737:chemistry; D004730:Endothelium, Vascular / Q000166:cytology*; D005167:Factor VII / Q000378:metabolism; D005312:Fetal Blood / Q000166:cytology; D005434:Flow Cytometry / Q000379:methods; D006801:Humans; D007249:Inflammation; D012306:Risk; D013917:Thrombin / Q000378:metabolism*; D013925:Thromboplastin / Q000378:metabolism*; D013927:Thrombosis; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D015854:Up-Regulation; D014945:Wound Healing
chemical_list: D003029:Coagulants; D014409:Tumor Necrosis Factor-alpha; D005167:Factor VII; D013925:Thromboplastin; D013917:Thrombin