Chevallier Pascale, Janvier Richard, Mantovani Diego, Laroche Gaétan
Unité de Biotechnologie et de Bioingénierie, Centre de Recherche de l'Hôpital Saint-François d'Assise, CHUQ, 10 rue de l'Espinay, Québec G1L 3L5, Canada.
Macromol Biosci. 2005 Sep 16;5(9):829-39. doi: 10.1002/mabi.200500088.
Arterial prostheses made of microporous Teflon (ePTFE) are currently used in vascular surgery as bypasses for small and medium vessels. However, several clinical complications, such as thrombosis, frequently occur in these prostheses when implanted in humans. In this work, an original strategy was developed to improve the hemocompatibility of ePTFE prostheses, based on glow-discharge surface modification followed by chemical grafting of phosphorylcholine, known for its hemocompatible properties. This procedure leads to a covalent attachment of the molecules, therefore preventing their removal by shear stress induced by blood flow at the implant wall. The improvement of the blood compatibility properties of the modified ePTFE arterial prostheses have been investigated by in vitro tests such as thromboelastography, neutrophil adsorption, platelet aggregation, and cell cultures. These in vitro tests put in evidence that thrombogenicity index, platelet aggregation, and neutrophil adhesion were decreased by the molecule grafted on the prostheses. Moreover, the cell growth on the surface of the PRC-grafted prostheses was greatly enhanced in comparison to the virgin prosthesis. Based on these results, it could be concluded that PRC grafting on ePTFE prostheses permit to improve in vitro hemocompatibility and biocompatibility in comparison with their virgin counterpart.
由微孔聚四氟乙烯（ePTFE）制成的动脉假体目前在血管外科中用作中小血管的旁路。然而，这些假体植入人体后经常会出现一些临床并发症，如血栓形成。在这项工作中，基于辉光放电表面改性，随后进行具有血液相容性的磷酰胆碱化学接枝，开发了一种改善ePTFE假体血液相容性的原始策略。该过程导致分子的共价连接，因此可防止它们因植入物壁处血流引起的剪切应力而被去除。通过体外测试，如血栓弹性描记法、中性粒细胞吸附、血小板聚集和细胞培养，研究了改性ePTFE动脉假体血液相容性的改善情况。这些体外测试表明，接枝在假体上的分子降低了血栓形成指数、血小板聚集和中性粒细胞粘附。此外，与原始假体相比，PRC接枝假体表面的细胞生长大大增强。基于这些结果，可以得出结论，与原始的ePTFE假体相比，PRC接枝在ePTFE假体上能够改善体外血液相容性和生物相容性。
