中文摘要：

背景：聚左旋乳酸（PLLA）支架材料在生物材料领域中尤其是组织工程学中应用广泛,但亲水性较低、缺乏表面细胞结合位点和细胞黏附性较差等缺点制约着其进一步应用。目的：体外实验观察小鼠神经干细胞与多壁碳纳米管/聚左旋乳酸（MWCNTs/PLLA）纳米纤维支架材料复合培养的生长状况并检测其生物相容性。方法：分离培养小鼠神经干细胞,静电纺丝法制备PLLA纳米纤维支架材料并用MWCNTs修饰;取第3代神经干细胞分别接种于PLLA与MWCNTs/PLLA纳米纤维支架材料上,进行体外培养。结果与结论：1神经干细胞在PLLA及MWCNTs/PLLA支架材料中生存良好,材料无明显毒性;2神经干细胞在MWCNTs/PLLA材料上表现出比PLLA支架材料更加优异的细胞黏附能力及增殖能力;3扫描电镜及Hoechst 33342染色显示神经干细胞在材料表面生长良好,形态正常;4免疫荧光MAP2染色显示神经干细胞在MWCNTs/PLLA支架材料上生长并分化为成熟神经元,且神经元突起生长方向与纳米纤维支架方向一致;5结果表明,MWCNTs/PLLA纳米纤维支架材料的细胞相容性良好,能为神经干细胞提供良好的生长载体且有定向诱导分化为神经元突起的作用,是组织工程学修复脊髓损伤的理想支架材料。

英文摘要：

BACKGROUND： Poly（L-lactic acid）（PLLA） scaffold is a kind of widely used biomaterial in tissue engineering. However, low hydrophilicity and lack of surface cell recognition site of PLLA hinder its further application. OBJECTIVE： To study the biocompatibility of multi-walled carbon nanotubes/PLLA（MWCNTs/PLLA） nanofiber scaffolds with mouse neural stem cells in vitro.METHODS： Mouse neural stem cells were isolated. Then we used electrospinning to fabricate PLLA nanofibers and modified them with multi-walled carbon nanotubes. We assessed their biocompatibility with passage 3 mouse neural stem cells in vitro. RESULTS AND CONCLUSION： Scanning electron microscope showed that the neural stem cells could survive on both scaffolds. No cytotoxic effects were detected on both scaffolds by Cell Counting Kit-8 detection. The adhesion and proliferation abilities of neural stem cells on the MWCNTs/PLLA scaffold were significantly greater than those on the PLLA scaffold. Neural stem cells were found grow well and have normal morphology on both scaffolds under scanning electron microscope and by Hoechst 33342 staining. Besides, immunofluorescence staining showed MWCNTs/PLLA could promote neural stem cells to differentiate into mature neurons and neurites grew along with the nanofiber scaffold. In conclusion, the MWCNTs/PLLA nanofiber scaffold has better properties than the PLLA for transplanted cells and provides a good growth carrier for neural stem cells to be induced to differentiate into neurons, which is expected to have a great potential of applications in nerve tissue engineering.