【摘要】 背景:脊髓损伤后,由于有胶质瘢痕的阻隔,使再生的轴突难以穿越损伤区域,从而影响脊髓功能的恢复。随着组织工程技术的发展,研究人员尝试利用在三维支架的空间诱导作用下,让再生的轴突和支架内部携带的细胞能够三维有序的生长,穿越瘢痕屏障,连接脊髓损伤断端。目的:采用编织工艺研制新型以聚乙交酯-丙交酯为原料的三维支架,检测新型支架与许旺细胞的生物相容性。设计、时间及地点:体外对比观察实验,于2007-06/2008-03在长海医院中心实验室完成。材料:选择聚乳酸︰聚羟基乙酸为9︰1的聚合材料聚乙交酯-丙交酯,通过熔融纺丝、拉伸、编织等步骤制作聚乙交酯-丙交酯三维支架。取新生3dSD乳鼠的坐骨神经,分离、纯化许旺细胞。方法:实验分3组:三维支架组将许旺细胞接种在新型三维支架内培养;明胶海绵组将许旺细胞接种在胶原海绵上培养;细胞培养皿组直接接种在预涂左旋多聚赖氨酸的24孔培养板上培养。主要观察指标:扫描电镜观察内部微管道的排列规律,测量其孔径大小、孔隙率等指标。通过倒置相差显微镜和扫描电镜观察许旺细胞在支架上生长情况,包括许旺细胞在支架上的黏附、增殖和凋亡情况等。结果:支架外径为3mm,微管道内径为100μm,呈均匀平行排列,支架的孔隙率为68%。三维支架组与细胞培养皿组中的许旺细胞黏附、增殖差异无显著性意义,与明胶海绵组差异有显著性意义。三维支架组与明胶海绵组中细胞凋亡差异无显著性意义,它们均低于细胞培养皿组,差异有显著性意义。结论:新型三维编织型支架具有良好的生物相容性。更多还原

【Abstract】 BACKGROUND:After spinal cord injury,it is difficult for axon to go through injured sites due to the glial scar barriers,which would been harmful to functional restoration of spinal cord. With the development of tissue engineering techniques,the researchers tried to use the three-dimensional scaffolds,which induced regenerated axons and cells at internal side to grow through the scar barrier in an order manner,connecting the ends of spinal cord injury. OBJECTIVE:A novel weaving method for the copolymers poly lactide-co-glycolide acid (PLGA) was developed to construct three-dimensional scaffold. Culturing of Schwann cells on the novel scaffolds demonstrated its biocompatibility. DESIGN,TIME AND SETTING:An in vitro comparative observational experiment was performed at Central Laboratory of Changhai Hospital from June 2007 to March 2008. MATERIALS:Three-dimensional waven scaffolds were produced by the copolymers PLGA (polylactic acid :polyglycolic acid = 9 :1) via melt spinning,extension,and weaving. Bilateral sciatic nerves were harvested from 3-day-old SD rats for culture and identification of Schwann cells. METHODS:The cells were randomly assigned into three groups:three-dimensional scaffold group (Schwann cells were cultured on the novel three-dimensional scaffold),gelatin sponge group (Schwann cells were cultured on the gelatin sponge),and culture media group (Schwann cells were cultured in poly-L-lysine (PLL) coated 24-well culture plate). MAIN OUTCOME MEASURES:The alignment regularities of micro-channels were observed under the scanning electronic microscope (SEM). The size of the micro-channels and the factor of porosity were also measured. The adherence,proliferation and apoptosis of Schwann cells on scaffolds were observed by inverted phase contrast microscopy and SEM. RESULTS:The outer diameter of scaffolds was 3 mm and the inner diameter of micro-channels was 100 μm. The micro-channels arrayed in parallel manners,and the factor of porosity was 68%. There was no significant difference in adherence and proliferation of Schwann cells cultured on PLGA and in culture media,but was significant difference compared with gelatin sponge. There was no significant difference in apoptosis of Schwann cells on PLGA and on gelatin sponge,but was significant difference compared with culture media. CONCLUSION:The novel three-dimensional scaffold has an excellent biocompatibility.更多还原