Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, 23298, USA.
Acta Biomater. 2011 Jan;7(1):203-15. doi: 10.1016/j.actbio.2010.08.004. Epub 2010 Aug 19.
We describe the structural and functional properties of three-dimensional (3D) nerve guides fabricated from poly-ε-caprolactone (PCL) using the air gap electrospinning process. This process makes it possible to deposit nano-to-micron diameter fibers into linear bundles that are aligned in parallel with the long axis of a cylindrical construct. By varying starting electrospinning conditions it is possible to modulate scaffold material properties and void space volume. The architecture of these constructs provides thousands of potential channels to direct axon growth. In cell culture functional assays, scaffolds composed of individual PCL fibers ranging from 400 to 1500 nm supported the penetration and growth of axons from rat dorsal root ganglion. To test the efficacy of our guide design we reconstructed 10mm lesions in the rodent sciatic nerve with scaffolds that had fibers 1 μm in average diameter and void volumes >90%. Seven weeks post implantation, microscopic examination of the regenerating tissue revealed dense, parallel arrays of myelinated and non-myelinated axons. Functional blood vessels were scattered throughout the implant. We speculate that end organ targeting might be improved in nerve injuries if axons can be directed to regenerate along specific tissue planes by a guide composed of 3D fiber arrays.
我们描述了使用气隙静电纺丝工艺制造的三维（3D）神经导管的结构和功能特性。该工艺使得能够将纳米至微米直径的纤维沉积到与圆柱形结构的长轴平行的线性束中。通过改变起始静电纺丝条件，可以调节支架材料的性质和空隙体积。这些结构的架构为引导轴突生长提供了数千个潜在的通道。在细胞培养功能测定中，由直径在 400 至 1500nm 之间的单个 PCL 纤维组成的支架支持大鼠背根神经节轴突的穿透和生长。为了测试我们的引导设计的效果，我们用平均直径为 1μm 且空隙体积大于 90%的纤维重建了啮齿动物坐骨神经的 10mm 损伤。植入后 7 周，对再生组织的显微镜检查显示出密集的、平行排列的有髓和无髓轴突。功能性血管散布在整个植入物中。我们推测，如果通过由 3D 纤维阵列组成的引导物可以引导轴突沿着特定的组织平面再生，那么在神经损伤中，靶器官的靶向可能会得到改善。
