Sturge J, Carey N, Davies A H, Powell J T
Department of Vascular Surgery, Imperial College School of Science, Technology, and Medicine, London, UK.
J Vasc Surg. 2001 Apr;33(4):847-53. doi: 10.1067/mva.2001.111984.
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.
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.
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).
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.
我们研究了以下假说，即纤维蛋白原可增加从人隐静脉培养的平滑肌细胞（SMC）的DNA合成（及细胞增殖），且当细胞在聚合胶原蛋白上培养时，增加的DNA合成会减弱。
从人隐静脉中分离出的SMC在塑料、纤连蛋白、单体胶原蛋白和聚合胶原蛋白上进行培养。通过蛋白水解消化制备纤维蛋白原产物。通过将溴脱氧尿苷掺入DNA来测量DNA合成，通过细胞计数来测量细胞增殖，通过酶联免疫吸附测定法来测量环磷酸腺苷，并用碘125标记的纤维蛋白肽B进行结合研究。
纤维蛋白单体（0.003 - 0.1微摩尔/升）刺激DNA合成呈浓度依赖性增加，最高可达10倍，该增加可被肽Bβ15 - 42抑制。对于在塑料上培养的细胞，DNA合成的刺激作用最高，而对于在I型胶原蛋白聚合物上培养的细胞，刺激作用最低。需要更高浓度的纤维蛋白原（0.3 - 1微摩尔/升）才能实现类似程度的DNA合成增加。当细胞在单体I型胶原蛋白上培养时，纤维蛋白原对增加DNA合成有特殊作用，可达14倍。这种增加的DNA合成被抗尿激酶型纤溶酶原激活剂的中和抗体所抑制。用纤维蛋白原孵育在胶原蛋白单体上培养的细胞会导致纤维蛋白肽B的产生。纤维蛋白肽B（5微摩尔/升）使DNA合成增加四倍，并与纤维蛋白单体具有协同增加DNA合成的作用。碘化酪氨酸纤维蛋白肽B与SMC结合（解离常数0.6微摩尔/升）。
培养的人隐静脉SMC似乎对纤维蛋白单体和纤维蛋白肽B具有高亲和力受体，其结合可刺激DNA合成。这些机制可能与体内纤维蛋白原和静脉移植物狭窄之间的关联有关。
