Diener J L, Daniel Lagassé H A, Duerschmied D, Merhi Y, Tanguay J-F, Hutabarat R, Gilbert J, Wagner D D, Schaub R
Immune Disease Institute and Department of Pathology, Harvard Medical School, Boston, MA, USA.
J Thromb Haemost. 2009 Jul;7(7):1155-62. doi: 10.1111/j.1538-7836.2009.03459.x. Epub 2009 Apr 24.
von Willebrand factor (VWF) has a role in both hemostasis and thrombosis. Platelets adhere to damaged arteries by interactions between the VWF A1-domain and glycoprotein Ib receptors under conditions of high shear. This initial platelet binding event stimulates platelet activation, recruitment, and activation of the clotting cascade, promoting thrombus formation.
To characterize the inhibitory activity of a VWF inhibitory aptamer.
Using in vitro selection, aptamer stabilization, and conjugation to a 20-kDa poly(ethylene glycol), we generated a nuclease-resistant aptamer, ARC1779, that binds to the VWF A1-domain with high affinity (K(D) approximately 2 nM). The aptamer was assessed for inhibition of VWF-induced platelet aggregation. In vitro inhibition of platelet adhesion was assessed on collagen-coated slides and injured pig aortic segments. In vivo activity was assessed in a cynomolgus monkey carotid electrical injury thrombosis model.
ARC1779 inhibited botrocetin-induced platelet aggregation (IC90 approximately 300 nM) and shear force-induced platelet aggregation (IC95 approximately 400 nM). It reduced adhesion of platelets to collagen-coated matrices and formation of platelet thrombi on denuded porcine arteries. ARC1779 also inhibited the formation of occlusive thrombi in cynomolgus monkeys. We have discovered a novel anti-VWF aptamer that could have therapeutic use as an anti-VWF agent in the setting of VWF-mediated thrombosis.
血管性血友病因子（VWF）在止血和血栓形成中均起作用。在高剪切力条件下，血小板通过VWF A1结构域与糖蛋白Ib受体之间的相互作用黏附于受损动脉。这一初始的血小板结合事件刺激血小板活化、募集以及凝血级联反应的激活，促进血栓形成。
表征一种VWF抑制性适体的抑制活性。
通过体外筛选、适体稳定化以及与20 kDa聚乙二醇偶联，我们生成了一种对核酸酶具有抗性的适体ARC1779，它以高亲和力（解离常数K(D)约为2 nM）结合VWF A1结构域。评估该适体对VWF诱导的血小板聚集的抑制作用。在胶原包被的载玻片和损伤的猪主动脉段上评估其对血小板黏附的体外抑制作用。在食蟹猴颈动脉电损伤血栓形成模型中评估其体内活性。
ARC1779抑制了蛇毒诱导的血小板聚集（IC90约为300 nM）和剪切力诱导的血小板聚集（IC95约为400 nM）。它减少了血小板与胶原包被基质的黏附以及在猪裸露动脉上血小板血栓的形成。ARC1779还抑制了食蟹猴中闭塞性血栓的形成。我们发现了一种新型抗VWF适体，在VWF介导的血栓形成情况下，它可作为抗VWF药物用于治疗。
