Key Laboratory of Advanced Technology for Materials of Chinese Education Ministry, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, People's Republic of China.
J Biomed Mater Res A. 2013 Apr;101(4):1144-57. doi: 10.1002/jbm.a.34392. Epub 2012 Oct 9.
The endothelialization of the metal surface of vascular stents came into focus as a new method for improving the biocompatibility of intravascular stents. This article has its focus on building a biofunctional layer on the activated titanium surface with anti-CD34 antibody, vascular endothelial growth factor (VEGF), and heparin by a layer-by-layer (LBL) self-assembly technique, to promote the endothelialization of the surface. When compared with titanium surface, the number of adhered endothelial progenitor cells (EPCs) on LBLs increased 47.1% after 5 days culture, meanwhile the proliferation rate of EPCs on LBLs during 5 days culture also exhibit significantly improvement. The results of blood compatibility evaluation clearly show that the LBLs reduce the number of adhered and activated blood platelets (adhered: Ti 83% vs. LBL <20% and activated: Ti 57% vs. LBL 19%), and the activated partial thromboplastin time of the LBL surface prolonged about 20 s in compared with platelet-poor plasma. The assembled LBL thus improves the thromboresistance of the titanium surface. The presented biofunctional multilayer of anti-CD34, VEGF, and heparin on titanium can significantly improve the blood compatibility and the endothelialization of a medical device. The biofunctional layer supports generation of a new endothelium onto titanium surface by capturing EPCs and oriented differentiation.
血管内支架金属表面的内皮化作为提高血管内支架生物相容性的新方法受到关注。本文主要研究了通过层层自组装技术在激活的钛表面构建带负电荷的抗 CD34 抗体、血管内皮生长因子(VEGF)和肝素的生物功能层，以促进表面的内皮化。与钛表面相比，培养 5 天后，LBL 上黏附的内皮祖细胞(EPC)数量增加了 47.1%，同时 EPC 在 LBL 上的增殖率也显著提高。血液相容性评价结果表明，LBL 减少了黏附的和激活的血小板数量(黏附：Ti 为 83%，LBL<20%；激活：Ti 为 57%，LBL 为 19%)，且 LBL 表面的激活部分凝血活酶时间比富血小板血浆延长约 20 s。因此，组装的 LBL 提高了钛表面的抗血栓性。本研究在钛表面组装带负电荷的抗 CD34、VEGF 和肝素的多功能多层膜，可以显著提高医疗器械的血液相容性和内皮化。生物功能层通过捕获 EPCs 和定向分化来支持在钛表面生成新的内皮。
