Recent studies have shown that 3D printed scaffolds integrated with growth factors can guide the growth of neurites and promote axon regeneration at the injury site. However, heat, organic solvents or cross-linking agents used in conventional 3D printing reduce the biological activity of growth factors. Low temperature 3D printing can incorporate growth factors into the scaffold and maintain their biological activity. In this study, we developed a collagen/chitosan scaffold integrated with brain-derived neurotrophic factor (3D-CC-BDNF) by low temperature extrusion 3D printing as a new type of artificial controlled release system, which could prolong the release of BDNF for the treatment of spinal cord injury (SCI). Eight weeks after the implantation of scaffolds in the transected lesion of T10 of the spinal cord, 3D-CC-BDNF significantly ameliorate locomotor function of the rats. Consistent with the recovery of locomotor function, 3D-CC-BDNF treatment could fill the gap, facilitate nerve fiber regeneration, accelerate the establishment of synaptic connections and enhance remyelination at the injury site.

中文翻译：

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集成打印的 BDNF/胶原蛋白/壳聚糖支架与低温挤压 3D 打印机加速脊髓损伤后的神经再生

最近的研究表明，结合生长因子的 3D 打印支架可以引导神经突的生长，促进损伤部位的轴突再生。然而，传统 3D 打印中使用的热量、有机溶剂或交联剂会降低生长因子的生物活性。低温3D打印可以将生长因子整合到支架中并保持其生物活性。在本研究中，我们通过低温挤压 3D 打印开发了一种与脑源性神经营养因子 (3D-CC-BDNF) 相结合的胶原蛋白/壳聚糖支架，作为一种新型的人工控释系统，可以延长 BDNF 的释放时间。脊髓损伤（SCI）的治疗。在脊髓 T10 横断病灶中植入支架后八周，3D-CC-BDNF 显着改善大鼠的运动功能。与运动功能的恢复相一致，3D-CC-BDNF 治疗可以填补空白，促进神经纤维再生，加速突触连接的建立，增强损伤部位的髓鞘再生。