Yao Li, O'Brien Norah, Windebank Anthony, Pandit Abhay
National Centre for Biomedical Engineering Science, National University of Ireland, Galway, Ireland.
J Biomed Mater Res B Appl Biomater. 2009 Aug;90(2):483-91. doi: 10.1002/jbm.b.31308.
In cases where direct suture of two nerve stumps is not feasible, generally a scaffold is required to bridge the gap and guide nerve regeneration. The scaffold used in nerve tissue engineering applications requires optimal guidance effect, mechanical strength, and cellular compatibility. A number of studies suggest that fibrous scaffolds can potentially be used for nerve regeneration, as the aligned fibers can provide the guidance effect for axonal growth and the fibrous structure mimics the nerve microenvironment. A practical method to fabricate the fibrous nerve conduit with structural guidance cue for neurite growth will improve its potential application in neural tissue engineering. In this study, fibrous tubular scaffolds were fabricated using an electrospinning technique. The fibrous conduit was composed of aligned fibers in the interior layer and randomly oriented fibers in the exterior layer. In order to investigate the fiber diameter on neurite extension and directional growth, fibers with different diameter in the subcellular size range were fabricated and the neurite growth on these fibers was investigated. We observed that PC12 cells' neurites showed similar parallel growth on the aligned fibers irrespective of fiber diameter. Neurite length on aligned fibers, with fiber diameters of 3.7 +/- 0.5 microm and 5.9 +/- 0.9 microm, was significantly longer than neurite length on randomly oriented fibers. This study showed that electrospinning provides a practical solution to fabricate fibrous nerve conduit by controlling the conduit inner diameter and fiber alignment and, hence, potentially improves the application of the conduit in neural regeneration.
在两个神经残端无法直接缝合的情况下，通常需要一个支架来桥接间隙并引导神经再生。神经组织工程应用中使用的支架需要具备最佳的引导效果、机械强度和细胞相容性。许多研究表明，纤维支架有可能用于神经再生，因为排列整齐的纤维可为轴突生长提供引导作用，且纤维结构模拟了神经微环境。一种制造具有引导神经突生长结构线索的纤维神经导管的实用方法将提高其在神经组织工程中的潜在应用价值。在本研究中，采用静电纺丝技术制备了纤维管状支架。纤维导管由内层排列整齐的纤维和外层随机取向的纤维组成。为了研究纤维直径对神经突延伸和方向性生长的影响，制备了亚细胞尺寸范围内不同直径的纤维，并研究了这些纤维上的神经突生长情况。我们观察到，无论纤维直径如何，PC12细胞的神经突在排列整齐的纤维上都呈现出相似的平行生长。纤维直径为3.7±0.5微米和5.9±0.9微米的排列整齐的纤维上的神经突长度明显长于随机取向纤维上的神经突长度。本研究表明，静电纺丝通过控制导管内径和纤维排列为制造纤维神经导管提供了一种实用的解决方案，从而有可能改善导管在神经再生中的应用。
