title: Monocyte adhesion to human saphenous vein in vitro.
abstract: Monocyte adhesion to endothelium is believed to be an initiating event in atherosclerosis both in arteries and in saphenous vein coronary artery bypass grafts. We have developed a method to quantify adhesion of 51Cr-labelled human blood monocytes to saphenous vein. Adhesion to the intimal surface was measured to uniform 6 mm diameter discs, the adventitia of which was embedded in a layer of inert silicone grease. The identity, number and location of bound cells was further defined by scanning electron microscopy. The proportion of monocytes adhering to discs of freshly-isolated vein was 7.1 +/- 1.2% (SE, n = 8), which was equivalent to 500 +/- 80 monocytes/mm2. The percentage of monocytes adhering was independent of the number of monocytes added in the range 5-50 x 10(4). Scanning micrographs showed 80% endothelial coverage with monocytes adhering preferentially but not exclusively to subendothelium. Endothelial removal increased monocyte adhesion by 1.60 +/- 0.15-fold (n = 8, P less than 0.01). Vein surgically prepared for use in coronary bypass surgery, had a 50% reduction in endothelial coverage and a small but non significant (1.14 +/- 0.13-fold, n = 8) increase in monocyte adhesion. Treatment of freshly-isolated vein for 4 h at 37 degrees C with 1 micrograms/ml of E. Coli endotoxin followed by extensive washing did not remove endothelium but increased monocyte adherence by 1.46 +/- 0.18-fold (n = 8, P less than 0.05). The proportion of monocytes adhering to veins which had been cultured for 14 days was similar to freshly isolated veins (6.4 +/- 0.8%, n = 7), but in cultured veins, monocytes adhered preferentially to cells with typical endothelial morphology. Endotoxin treatment of cultured freshly-isolated veins increased monocyte adhesion by 1.77 +/- 0.23-fold (n = 8, P less than 0.05). The data show that both endothelial activation, and exposure of subendothelium promote monocyte adhesion to human saphenous vein.
authors.affiliation: Department of Cardiology, University of Wales College of Medicine, Heath Park, Cardiff, U.K.
authors.forename: J P
authors.initials: JP
authors.lastname: Cooper
authors.forename: A C
authors.initials: AC
authors.lastname: Newby
mesh_terms: D002448:Cell Adhesion; D002455:Cell Division; D002860:Chromium Radioisotopes; D001026:Coronary Artery Bypass; D046508:Culture Techniques; D004730:Endothelium, Vascular / Q000166:cytology / Q000648:ultrastructure; D004731:Endotoxins / Q000494:pharmacology; D006801:Humans; D008855:Microscopy, Electron, Scanning; D009000:Monocytes / Q000502:physiology* / Q000648:ultrastructure; D012501:Saphenous Vein / Q000166:cytology* / Q000637:transplantation
chemical_list: D002860:Chromium Radioisotopes; D004731:Endotoxins; C044101:endotoxin, Escherichia coli