双层蛛丝蛋白血管支架的制备及其生物力学性能与细胞相容性研究

Preparation of bilayer spider silk protein vascular scaffold and its biomechanical properties and cell compatibility

目的应用静电纺丝法制备一种双层蛛丝蛋白血管支架,观察血管支架的微观结构,并研究其生物力学性能和细胞相容性。方法配制纺丝液,通过静电纺丝,以旋转接收棒为收集装置,制备(pNSR16/PCL/CS)/(pNSR16/PCL/Gt)双层蛛丝蛋白血管支架。探讨质量分数和管壁厚度对血管支架孔隙率、爆破强度、拉伸性能、缝合强度和水渗透性的影响,并检测血管支架的细胞毒性和细胞黏附性能。结果血管支架的微观结构为纤维随机分布的三维多孔网状,爆破强度、拉伸强度和缝合强度大小均与支架的质量分数和管壁厚度成正比,孔隙率、水渗透性和断裂伸长率大小与支架的质量分数和管壁厚度成反比。血管支架爆破强度的范围为43～150 kPa,高于生理血压;缝合强度高于0.19 N,符合体内移植要求;拉伸强度高于人体桡动脉血管,满足体内移植的要求;水渗透性为0.3～0.6 mL·min-1·cm-2。血管支架无细胞毒性,有利于内皮细胞细胞黏附及增殖。结论使用静电纺丝法制备双层蛛丝蛋白血管支架是可行的,其优异的生物力学性能和生物相容性能表明其能应用于体外组织工程血管的构建,具有进一步应用于血管移植物研究的前景,为临床应用奠定了一定的基础。

Objective To prepare a bilayer spider silk protein vascular scaffold using electrospinning, observe mi- crostructure of the vascular scaffold and study its biomechanical properties and cell compatibility. Methods Spin- ning solution was electrospun to prepare （pNSRI6/PCL/CS）/（pNSR16/PCL/Gt） bilayer spider silk protein vas- cular scaffold using rotating receiving rod as the collection device. The effects of mass fraction and wall thickness on the porosity, bursting strength, tensile properties, suture retention strength and water permeability of the vas- cular scaffold were investigated, and cytotoxicity and cell adhesion property of the vascular scaffold were tested. Results The vascular scaffold presented three-dimensional porous microstructure with randomly distributed fi- bers. The bursting strength, tensile strength and suture retention strength were directly proportional to mass frac- tion and wall thickness, but the porosity, water permeability and elongation at break were inversely proportional to mass fraction and wall thickness. The bursting strength range of vascular scaffold was 43 - 150 kPa, which was higher than the physiological blood pressure; the suture strength was above 0.19 N, which was consistent with the transplantation requirement in vivo; the tensile strength was higher than that of human radial artery, which met the transplantation requirement in vivo; the range of water permeability was 0.3 - 0.6 mL · min 1· cm-2 The vascular scaffold had no cytotoxicity and facilitated the adhesion and proliferation of endothelial cells. Conclu-sions It is feasible to prepare the bilayer spider silk protein vascular scaffold through electrospinning. The superi- or biomechanical properties and biocompatibility properties show that the bilayer spider silk protein vascular can be used for construction of the tissue engineered blood vessels in vitro, with prospect for further vascular graft study, which lays a foundation for its clinical application.