J Sturge1, N Carey, A H Davies, J T Powell. 1. Department of Vascular Surgery, Imperial College School of Science, Technology, and Medicine, London, UK.
Abstract
PURPOSE: We investigated the hypothesis that fibrinogen increased DNA synthesis (and cell proliferation) of smooth muscle cells (SMCs) cultured from human saphenous vein and that the increased DNA synthesis was attenuated when cells were cultured on polymeric collagen. METHODS: SMCs were cultured from human saphenous vein on plastic, fibronectin, monomeric, and polymeric collagen. Fibrinogen products were prepared by proteolytic digestion. DNA synthesis was measured by bromodeoxyuridine incorporation into DNA, cell proliferation by cell counting, cyclic adenosine monophosphate by enzyme-linked immunosorbent assay, and fibrinopeptide B labeled with iodine 125 used for binding studies. RESULTS: Fibrin monomer (0.003-0.1 micromol/L) stimulated a concentration-dependent increase in DNA synthesis of up to 10-fold, which could be inhibited by the peptide Bbeta15-42. The stimulation of DNA synthesis was highest for cells cultured on plastic and lowest for cells cultured on type I collagen polymer. Much higher concentrations of fibrinogen (0.3-1 micromol/L) were required to effect similar increases in DNA synthesis. Fibrinogen had a particular effect to augment DNA synthesis, up to 14-fold, when cells were cultured on monomeric type I collagen. This augmented DNA synthesis was inhibited by a neutralizing antibody to urokinase-type plasminogen activator. Incubation of cells cultured on collagen monomer with fibrinogen resulted in production of fibrinopeptide B. Fibrinopeptide B (5 micromol/L) increased DNA synthesis by fourfold and had additive effects with fibrin monomer to increase DNA synthesis. Iodinated tyrosine fibrinopeptide B bound to SMCs (dissociation constant 0.6 micromol/L). CONCLUSION: Cultured human saphenous vein SMCs appear to have high-affinity receptors for fibrin monomer and fibrinopeptide B, the engagement of which stimulates DNA synthesis. These mechanisms may be pertinent to the association between fibrinogen and vein graft stenosis in vivo.
PURPOSE: We investigated the hypothesis that fibrinogen increased DNA synthesis (and cell proliferation) of smooth muscle cells (SMCs) cultured from human saphenous vein and that the increased DNA synthesis was attenuated when cells were cultured on polymeric collagen. METHODS: SMCs were cultured from human saphenous vein on plastic, fibronectin, monomeric, and polymeric collagen. Fibrinogen products were prepared by proteolytic digestion. DNA synthesis was measured by bromodeoxyuridine incorporation into DNA, cell proliferation by cell counting, cyclic adenosine monophosphate by enzyme-linked immunosorbent assay, and fibrinopeptide B labeled with iodine 125 used for binding studies. RESULTS: Fibrin monomer (0.003-0.1 micromol/L) stimulated a concentration-dependent increase in DNA synthesis of up to 10-fold, which could be inhibited by the peptide Bbeta15-42. The stimulation of DNA synthesis was highest for cells cultured on plastic and lowest for cells cultured on type I collagen polymer. Much higher concentrations of fibrinogen (0.3-1 micromol/L) were required to effect similar increases in DNA synthesis. Fibrinogen had a particular effect to augment DNA synthesis, up to 14-fold, when cells were cultured on monomeric type I collagen. This augmented DNA synthesis was inhibited by a neutralizing antibody to urokinase-type plasminogen activator. Incubation of cells cultured on collagen monomer with fibrinogen resulted in production of fibrinopeptide B. Fibrinopeptide B (5 micromol/L) increased DNA synthesis by fourfold and had additive effects with fibrin monomer to increase DNA synthesis. Iodinated tyrosine fibrinopeptide B bound to SMCs (dissociation constant 0.6 micromol/L). CONCLUSION: Cultured human saphenous vein SMCs appear to have high-affinity receptors for fibrin monomer and fibrinopeptide B, the engagement of which stimulates DNA synthesis. These mechanisms may be pertinent to the association between fibrinogen and vein graft stenosis in vivo.
Authors: Diana C Ardila; Ehab Tamimi; Forest L Danford; Darren G Haskett; Robert S Kellar; Tom Doetschman; Jonathan P Vande Geest Journal: Biomaterials Date: 2014-10-22 Impact factor: 12.479
Authors: Luke P Brewster; Cicely Washington; Eric M Brey; Andrew Gassman; Anu Subramanian; Jen Calceterra; William Wolf; Connie L Hall; William H Velander; Wilson H Burgess; Howard P Greisler Journal: Biomaterials Date: 2007-10-22 Impact factor: 12.479