Zhang Quanchao, He Shan, Zhu Xiangbo, Luo Honglin, Gama Miguel, Peng Mengxia, Deng Xiaoyan, Wan Yizao
Jiangxi Key Laboratory of Nanobiomaterials, Institute of Advanced Materials, East China Jiaotong University, Nanchang 330013, China.
Jiangxi Key Laboratory of Nanobiomaterials, Institute of Advanced Materials, East China Jiaotong University, Nanchang 330013, China; School of Materials Science and Engineering, Tianjin University, Tianjin 300072, China.
Mater Sci Eng C Mater Biol Appl. 2021 Mar;122:111861. doi: 10.1016/j.msec.2020.111861. Epub 2021 Jan 7.
Constructing biomimetic structure and immobilizing antithrombus factors are two effective methods to ensure rapid endothelialization and long-term anticoagulation for small-diameter vascular grafts. However, few literatures are available regarding simultaneous implementation of these two strategies. Herein, a nano-micro-fibrous biomimetic graft with a heparin coating was prepared via a step-by-step in situ biosynthesis method to improve potential endothelialization and anticoagulation. The 4-mm-diameter tubular graft consists of electrospun cellulose acetate (CA) microfibers and entangled bacterial nanocellulose (BNC) nanofibers with heparin coating on dual fibers. The hybridized and heparinized graft possesses suitable pore structure that facilitates endothelia cells adhesion and proliferation but prevents infiltration of fibrous tissue and blood leakage. In addition, it shows higher mechanical properties than those of bare CA and hybridized CA/BNC grafts, which match well with native blood vessels. Moreover, this dually modified graft exhibits improved blood compatibility and endothelialization over the counterparts without hybridization or heparinization according to the testing results of platelet adhesion, cell morphology, and protein expression of von Willebrand Factor. This novel graft with dual modifications shows promising as a new small-diameter vascular graft. This study provides a guidance for promoting endothelialization and blood compatibility by dual modifications of biomimetic structure and immobilized bioactive molecules.
构建仿生结构和固定抗血栓因子是确保小口径血管移植物快速内皮化和长期抗凝的两种有效方法。然而，关于同时实施这两种策略的文献却很少。在此，通过逐步原位生物合成方法制备了一种具有肝素涂层的纳米-微纤维仿生移植物，以提高其潜在的内皮化和抗凝性能。直径4毫米的管状移植物由静电纺丝醋酸纤维素（CA）微纤维和缠结的细菌纳米纤维素（BNC）纳米纤维组成，双纤维上均有肝素涂层。这种杂交且肝素化的移植物具有合适的孔隙结构，有利于内皮细胞的黏附和增殖，但能防止纤维组织的浸润和血液渗漏。此外，它的机械性能比裸露的CA和杂交的CA/BNC移植物更高，与天然血管匹配良好。而且，根据血小板黏附、细胞形态和血管性血友病因子蛋白表达的测试结果，这种双重修饰的移植物比未杂交或未肝素化的对应物表现出更好的血液相容性和内皮化。这种新型的双重修饰移植物有望成为一种新型的小口径血管移植物。本研究为通过仿生结构和固定化生物活性分子的双重修饰来促进内皮化和血液相容性提供了指导。
