Replacement of peripheral nerve autografts with tissue engineered nerve grafts will potentially resolve the lack of nerve tissue especially in patients with severe concomitant soft tissue injuries. This study attempted to fabricate a tissue engineered nerve graft composed of electrospun PCL conduit filled with collagen‐hyaluronic acid (COL‐HA) sponge with different COL‐HA weight ratios including 100:0, 98:2, 95:5 and 90:10. The effect of HA addition on the sponge porosity, mechanical properties, water absorption and degradation rate was assessed. A good cohesion between the electrospun PCL nanofibers and COL‐HA sponges were seen in all sponges with different HA contents. Mechanical properties of PCL nanofibrous layer were similar to the rat sciatic nerve; the ultimate tensile strength was 2.23 ± 0.35 MPa at the elongation of 35%. Additionally, Schwann cell proliferation and morphology on three dimensional (3D) composite scaffold were evaluated by using MTT and SEM assays, respectively. Rising the HA content resulted in higher water absorption as well as greater pore size and porosity, while a decrease in Schwann cell proliferation compared to pure collagen sponge, although reduction in cell proliferation was not statistically significant. The lower Schwann cell proliferation on the COL‐HA was attributed to the greater degradation rate and pore size of the COL‐HA sponges. Also, dorsal root ganglion assay showed that the engineered 3D construct significantly increases axon growth. Taken together, these results suggest that the fabricated 3D composite scaffold provide a permissive environment for Schwann cells proliferation and maturation and can encourage axon growth.

中文翻译：

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基于胶原蛋白/透明质酸海绵和电纺聚己内酯纳米纤维的用于周围神经再生的3D复合支架的制备和体外评价。

用组织工程神经移植物替代周围神经自体移植物可能会解决神经组织缺乏的问题，尤其是在伴有严重软组织损伤的患者中。本研究试图制造一种组织工程神经移植物，由充满胶原-透明质酸 (COL-HA) 海绵的电纺 PCL 导管组成，具有不同的 COL-HA 重量比，包括 100:0、98:2、95:5 和 90:10 . 评估了添加 HA 对海绵孔隙率、机械性能、吸水率和降解率的影响。在具有不同 HA 含量的所有海绵中都观察到电纺 PCL 纳米纤维和 COL-HA 海绵之间的良好内聚力。PCL纳米纤维层的力学性能与大鼠坐骨神经相似；在伸长率为 35% 时，极限拉伸强度为 2.23±0.35 MPa。此外，分别使用 MTT 和 SEM 测定法评估了三维 (3D) 复合支架上的雪旺氏细胞增殖和形态。增加 HA 含量导致更高的吸水率以及更大的孔径和孔隙率，而与纯胶原海绵相比，雪旺氏细胞增殖减少，尽管细胞增殖的减少没有统计学意义。COL-HA 上较低的雪旺氏细胞增殖归因于 COL-HA 海绵更大的降解速率和孔径。此外，背根神经节分析表明，工程化 3D 构建体显着增加了轴突生长。总之，这些结果表明制造的 3D 复合支架为雪旺细胞增殖和成熟提供了一个允许的环境，并可以促进轴突生长。