调控NSC定向分化的三维多肽水凝胶EPC捕捉支架的构建及其生物评价

With the development of biomaterials and tissue engineering, neural tissue engineering was considered to be the best approach for nerve injury repair. However, the lack of biological activity and the short half-life of the loading cytokines of scaffolds, and the lack of blood supply during the repair process have limited its clinical application. In this project, we will design a RADA16-I peptide hydrogel scaffolds which encapsulated the endothelial progenitor cells (EPC) nucleic acid aptamer and its C-terminal chemically bonded the nerve growth factor (NGF) functional peptide short motifs. EPC-capturing neural tissue engineering scaffolds will constructed by the multifunctional hydrogel assembled on three-dimensional porous biomaterials via inkjet printing method.This study would optimize the NSC/EPC co-culture conditions to regulate the neural differentiation of NSC and promote the vascular endothelialization with a high EPC capturing efficiency in vitro, and the evaluating of nerve and vascular repair of rat sciatic nerve models will also be performed. The purpose of the project is to provide a promising approach for the design of neural tissue engineering scaffolds with significant functional advantages, and to provide experimental evidence for the reconstruction of complex nerve microenvironment.

随着生物材料和组织工程技术的发展，神经组织工程被认为是最理想的神经损伤修复方法，但支架材料的生物活性不足、负载生物因子的作用时间有限、修复过程中血供不足等因素均阻碍了其临床应用进程。本项目将设计制备包埋了内皮祖细胞（EPC）核酸适配体的、C末端以化学键连接了神经生长因子（NGF）功能短肽片段的RADA16-I多肽水凝胶材料，并通过喷射打印的方式将其组装到生物相容性优异的三维多孔基底材料的表面和孔道内部，构建可调控神经干细胞（NSC）神经分化、特异性捕捉EPC促进血管内皮化的多功能三维复合神经支架材料。优化NSC/EPC共培养条件，高效调控NSC向神经元分化和神经细胞功能的恢复，提高体外模拟外周血循环条件下EPC捕捉效率促进血管内皮化，并评估其对大鼠坐骨神经缺损模型的神经修复和血管化情况。目的旨在提供一种新的功能优势明显的神经组织工程支架材料制备方法，为神经组织复杂微环境的重建提供实验依据。