Institute of Orthopedics, Xijing Hospital, The Fourth Military Medical University, Xi'an 710032, China.
Regen Med. 2011 Jul;6(4):437-47. doi: 10.2217/rme.11.39.
Scaffold with micro-channels has shown great promise in facilitating axonal regeneration after peripheral nerve injury. Significant research has focused on mimicking, in terms of composition and function, the ability of the basement membrane of Schwann cells to both promote and guide axonal regeneration. We aim to investigate the ability of a tissue-engineered scaffold with nanosilver and collagen to adsorb laminin and fibronectin, and the usefulness of this scaffold for repairing and regenerating a 10-mm peripheral nerve gap in rats.
In this study, nanosilver-embedded collagen scaffolds were prepared and coated with laminin (LN) or LN plus fibronectin (FN). Scanning electron microscopy of the transverse and longitudinal sections of the scaffold revealed axially oriented microtubules ranging from 20 to 80 µm in diameter, and the internal surface of microtubules was found to be evenly coated with LN and FN. Energy dispersive spectrometry also confirmed an even distribution of nanosilver particles within the scaffold. To test its effectiveness in restoring neuronal connection, the scaffold was used in order to bridge 10 mm gaps in the severed sciatic nerve of rats. The rats were divided into an experimental group (receiving scaffold coated with LN and FN), a control group (receiving scaffold coated with LN only) and an autologous graft group. The functional recovery 40 days after surgery was examined by electrophysiology and sciatic nerve functional index (SFI) evaluation. FluoroGold™ (FG) retrograde tracing, toluidine blue staining and transmission electron microscopy were also used to examine the regenerated nerve fibers and to establish their myelination status.
The experimental group displayed partially restored nerve function. The recovery was comparable to the effect of autologous nerve graft and was better than that observed in the control group. A better functional recovery correlated with more FG-labeled neurons, higher density of toluidine blue stained nerve fibers and thicker myelin sheath.
Our results demonstrated that nanosilver-embedded collagen scaffolds with LN and FN coating is effective in aiding axonal regeneration, and recovery is comparable to the effect of an autologous nerve graft.
具有微通道的支架在促进周围神经损伤后的轴突再生方面显示出巨大的潜力。大量研究集中在模拟施万细胞基底膜的组成和功能，以促进和引导轴突再生。我们旨在研究纳米银和胶原组织工程支架吸附层粘连蛋白和纤维连接蛋白的能力，以及该支架在修复和再生大鼠 10mm 周围神经间隙中的用途。
在这项研究中，制备了纳米银嵌入胶原支架，并涂覆层粘连蛋白（LN）或 LN 加纤维连接蛋白（FN）。支架的纵横截面扫描电子显微镜显示，直径为 20-80μm 的轴向微管，微管的内表面均匀涂覆有 LN 和 FN。能谱分析也证实纳米银颗粒在支架内均匀分布。为了测试其在恢复神经元连接方面的有效性，该支架用于桥接大鼠切断的坐骨神经 10mm 间隙。大鼠分为实验组（接受涂覆 LN 和 FN 的支架）、对照组（接受涂覆 LN 支架）和自体移植物组。术后 40 天通过电生理学和坐骨神经功能指数（SFI）评估检查功能恢复情况。还使用荧光金（FG）逆行示踪、甲苯胺蓝染色和透射电子显微镜检查再生神经纤维并确定其髓鞘化状态。
实验组显示部分神经功能恢复。恢复效果可与自体神经移植物的效果相媲美，优于对照组。更好的功能恢复与更多的 FG 标记神经元、更高密度的甲苯胺蓝染色神经纤维和更厚的髓鞘相关。
我们的结果表明，涂覆 LN 和 FN 的纳米银嵌入胶原支架在促进轴突再生方面是有效的，并且恢复效果可与自体神经移植物的效果相媲美。
