功能化水凝胶复合改性脱细胞血管对面神经趋向性再生的作用及机制研究

Facial nerve defect is difficult to repair in maxillofacial and peripheral nerve defect. In recent years, many scholars have made a lot of attempts to repair facial nerve defect. In the field of nerve scaffold materials, people are committed to simulating the three-dimensional scaffold structure of natural nerves, and some progress has been made, but it still can not provide an ideal three-dimensional micro-environment for nerve regeneration. Our previous experiments have carried out a series of studies on facial nerve defect repair and signaling pathway. . According to the experimental basis, the following experimental designs were proposed: 1. Grafting GDNF gene to fibrin hydrogel through biotin-avidin system to form functional hydrogel, which is co-cultured with Schwann-like cells in vitro to observe whether functional hydrogel can promote Schwann-like cells. Growth and activation of PI3K/AKT signaling pathway will be explored. 2. The modified acellular blood vessel was formed by printing polycaprolactone onto the surface of acellular blood vessel in 3D. The biomechanical and biocompatibility of the modified acellular blood vessel will be tested. 3. Using modified acellular blood vessels as external scaffolds, functional hydrogels as internal scaffolds, and composite Schwann-like cells to repair facial nerve defects, the mechanism of Schwann-like cells and the signal pathway of facial nerve regeneration were explored.

面神经缺损是颌面部及周围神经缺损修复的难题，近年来众多学者对面神经缺损的修复进行了大量的尝试。在神经支架材料方面人们致力于模拟天然神经的三维支架结构，并取得了一定的进展，但仍不能为神经再生提供理想的三维微环境。我们前期实验曾就面神经缺损修复及信号通路进行了一系列研究，根据实验基础，提出以下实验设计：1、通过生物素-亲和素系统将GDNF基因接枝至纤维蛋白水凝胶形成功能化水凝胶，将其与类雪旺细胞进行体外三维共培养，观察功能化水凝胶能否促进类雪旺细胞的生长，并对其是否激活PI3K/AKT信号通路进行探索。2、将聚己内酯3D打印至脱细胞血管表面形成改性脱细胞血管，对其生物力学及生物相容性等性能进行检测。3、利用改性脱细胞血管作为外支架，功能化水凝胶为内支架，复合类雪旺细胞修复面神经缺损，对类雪旺细胞发挥作用的机制及面神经趋向性再生的信号通路进行探索。

面神经缺损是颌面部及周围神经缺损修复的难题，在神经支架材料方面人们致力于模拟天然神经的三维支架结构，并取得了一定的进展，但仍不能为神经再生提供理想的三维微环境。本项目对功能化水凝胶材料复合牙髓干细胞修复面神经缺损进行了体内外一系列探索研究，并对其机制进行了探索，研究成果如下：1、将脱细胞血管外表面 3D 打印一层 PCL 材料，形成改性脱细胞血管，并对其性能进行检测，该导管既保留了良好的生物相容性，又避免了血管材料易塌陷的缺点。 2、成功的体外构建功能化纳米纤维蛋白水凝胶，体外将牙髓干细胞置于水凝胶上，检测其可促进牙髓干细胞向类雪旺细胞转化，对其机制进行探索，发现其体外通过激活PI3K/AKT信号通路促进其生长分化。3、利用改性脱细胞血管为外支架，功能化水凝胶复合类雪旺细胞修复大鼠面神经缺损，实验证实复合材料可成功的修复面神经缺损，促进面神经功能的恢复。本研究证实PI3K/AKT信号通路在牙髓干细胞生长分化过程中发挥了重要的作用，本研究对面神经缺损修复复合材料的研发可提供实验及理论基础，有助于将来更好的探索面神经缺损修复的机制。