单层组织工程纤维环取向纳米纤维支架的构建和初步验证

Fabrication of electrospun aligned poly( l-lactide-co-caprolactone) nanofibrous scaffolds for annulus fibrosus tissue engineering

目的使用静电纺丝技术构建取向纳米纤维支架,观测其结构,测试其力学特点,观察支架与细胞之间的相互作用,探讨其作为纤维环组织工程支架的可能性。方法使用高速滚轴作为收集装置制备聚左旋乳酸聚己内酯[poly(lactic acid-co-caprolactone,P(LLA-CL)]取向纳米纤维支架。以P(LLA-CL)无规纳米纤维支架作为对照,观察取向纳米纤维支架的纤维直径、角度分布、孔径等表观指标;测试其拉伸力学行为;体外接种骨髓间充质干细胞观察其体外增殖和生长形态情况。结果 P(LLA-CL)取向纳米纤维支架纤维取向性良好,平行于纤维方向上的拉伸力学性能得到明显增强。接种细胞后,支架可促进细胞增殖,并诱导细胞沿着纤维方向拉伸并定向排列。结论取向纳米纤维支架的力学强度在取向方向上得到了明显增强,具有和单层纤维环相似的各向异性力学特点,并可以诱导细胞沿纤维方向定向排列,细胞分布与纤维环细胞排列方式相似,可用于纤维环组织工程研究。

Objective To fabricate electrospun aligned poly（L-Lactide-co-Caprolactone） [P（LLA-CL）] nanofibrous scaffolds for annulus fibrosus tissue engineering and investigate the morphology,mechanical properties of the scaffolds and the cell behaviors on the scaffolds.Methods Electrospun aligned P （LLA-CL） nanofibers were collected by a high-speed mandrel.The morphological feature of scaffolds were observed by scanning electron microscopy.The mechanical properties of electrospun scaffolds were assayed by an optical microscope and digital image correlation testing device.Cell counting kit-8 （CCK-8）method was used to determine cell proliferation.Cell morphology was imaged by a laser scanning confocal microscopy.Electropun random P（LLA-CL） nanofibrous scaffold was served as a control.Results The morphological images revealed that fibers of the aligned nanofibrous scaffolds were highly oriented spread.The mechanical tests indicated that the mechanical properties of aligned nanofibrous scaffold were reinforced in the parallel direction of fibers and met the mechanical requirements for annulus fibrosus regeneration.Biocompatibility results showed that bone marrow-derived mesenchymal stem cells cultured on the aligned nanofibrous scaffolds were aligned and elongated along the direction of nanofibers.Conclusion With their superior physical properties and ability to better replicate annulus fibrosus tissue,the electrospun aligned P （LLA-CL） nanofibrous scaffolds warrant greater investigation as synthetic grafts in annulus fibrosus tissue engineering.