title: Suppression of ICAM-1 in human venous endothelial cells by small interfering RNAs.
abstract: OBJECTIVE
  Cardiopulmonary bypass-mediated release of proinflammatory cytokines promotes the transendothelial migration of leukocytes. Among others, intercellular adhesion molecule (ICAM) is essential for this migratory process within the venous bypass graft, which finally contributes to a diminished early patency rate by thickening of the intima. Small interfering ribonucleic acids (siRNAs) are efficient and specific modulators of endogenous gene expression. This study describes the application of siRNAs to suppress ICAM-1 expression on the surface of human venous endothelial cells.
  
  
  METHODS
  Primary cultures of human venous endothelial cells were either transfected with ICAM-1 siRNA, with a scrambled control siRNA or cultured without transfection. ICAM-1 expression was analyzed with or without TNF-alpha stimulation by flow cytometry.
  
  
  RESULTS
  Upon TNF-alpha stimulation, cells transfected with ICAM-1 siRNA showed a six- to seven-fold decreased ICAM-1 expression compared to untransfected cells or cells transfected with the scrambled control siRNA.
  
  
  CONCLUSIONS
  This is the first report that ICAM-1 expression can be effectively silenced by siRNAs on endothelial cells from human saphenous veins. This new technology may render novel therapeutic concepts to reduce early graft failure by protecting venous bypass grafts against early intra- or postoperative leukocyte infiltration.
authors.affiliation: Department of Thoracic, Cardiac and Vascular Surgery, Tuebingen University Hospital, Hoppe-Seyler-Strasse 3, 72076 Tuebingen, Germany. tobias.walker@med.uni-tuebingen.de
authors.forename: Tobias
authors.initials: T
authors.lastname: Walker
authors.forename: Hans Peter
authors.initials: HP
authors.lastname: Wendel
authors.forename: Liane
authors.initials: L
authors.lastname: Tetzloff
authors.forename: Olaf
authors.initials: O
authors.lastname: Heidenreich
authors.forename: Gerhard
authors.initials: G
authors.lastname: Ziemer
mesh_terms: D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D042783:Endothelial Cells / Q000378:metabolism; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics*; D012501:Saphenous Vein / Q000378:metabolism; D014162:Transfection; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
chemical_list: D034741:RNA, Small Interfering; D014409:Tumor Necrosis Factor-alpha; D018799:Intercellular Adhesion Molecule-1