基质细胞衍生因子-1诱导神经干细胞靶向性迁移的实验研究

目的 观察基质细胞衍生因子-1(SDF-1)对神经干细胞(NSCs)迁移的影响.方法 由胚胎大鼠脑组织获取NSCs并进行传代培养和分化鉴定,使用流式细胞术检测NSCs纯度及SDF-1特异性受体CXCR4的表达情况,之后利用Blind-Well小室体外迁移体系观察不同浓度的SDF-1(0 ng/L、1 ng/mL、10 ng/mL、50 ng/mL、100 ng/mL、500 ng/mL和1000 ng/mL)对NSCs迁移数量的影响,并使用μ-载片观察SDF-1对NSCs迁移距离的影响.结果成功分离培养得到了能够在体外不断分裂增殖、具有多向分化潜能的NSCs,连续传3代后绝大部分细胞nestin表达阳性,nestin和CXCR4的共表达率达到80%左右.细胞趋化实验结果表明,SDF-1对NSCs有较强的趋化作用,随着SDF-1浓度的升高,发生迁移的细胞数量也随之增加,并于SDF-1浓度为500ng/mL时达到最高峰[(256.79±38.27)个细胞/每高倍视野].在μ-载片细胞生长通道两侧的SDF-1浓度梯度(500ng/mL→0ng/mL)作用下,由细胞克隆球迁出的细胞呈不对称分布,通常有更多的迁出细胞分布于趋化因子浓度较高的一侧,且该侧细胞的最大迁移距离也比对侧远.结论 SDF-1与其特异性受体CXCR4相巨作用能够诱导NSCs发生靶向性迁移.     

基质细胞衍生因子-1诱导神经干细胞靶向性迁移的实验研究

Objective To investigate the effect ofstromal cell derived factor-1 (SDF-1) on the regulation of neural stem cells (NSCs) migration.Methods NSCs were obtained from the cerebral cortex of embryonic rats and cultured in serum-free medium,and their stem cell properties were assessed by means of induced differentiation in vitro into neurons and astrocytes.After in vitro cell culture,the purity of NSCs and the co-expression rate of CXCR4/nestin were detected by flow cytometry.Blind-well chambers were employed to detect the chemotactic effects of SDF-1 by counting the cells which had crossed a 8 μm pore membrane when confronted with varying concentrations of SDF-1 (0,1,10,50,100,500 and 1000 ng/mL),and the distribution of cells migrated out of the same neurosphere was overviewed by μ-slides in the persistent concentration gradient of SDF-1.Results Neurospheres were formed by persistent proliferation of NSCs, which were capable of differentiating into neurons (β-tubulin+) and astrocytes (GFAP+) in media without mitogens,and flow cytometry analyses showed that most of the cultured cells expressed nestin and the co-expression rate of CXCR4/nestin was nearly 80%.SDF-1 showed great chemotaxis to NSCs,and the amount of cells having migrated through the membrane in 500 ng/ml SDF-1 group was higher than that in other groups (P<0.05).When the cells were confronted with a linear concentration gradient (from 500 to 0 ng/mL),which was generated by diffusion and stable for at least 48 h,the cells migrated out ofa neruosphere could distribute irregularly with more cells locating in the region of higher concentration of SDF-1 and longer migration distance away from the center of the neurosphere than the opposite.Conclusion SDF-1 binding to its specific receptor CXCR4 was capable of inducing NSCs migrating directionally to the source of SDF-1.     

小鼠pLVX-Wnt3a-IRES-ZsGreenl慢病毒载体的构建及神经干细胞转染

目的 构建共表达小鼠Wnt3a(mWnt3a)与绿色荧光蛋白(GFP)慢病毒载体,感染神经干细胞(NSCs),观察mWnt3a在NSCs中的表达.方法 利用同源重组技术将mWnt3a基因插入慢病毒载体pLVX-IRES-ZsGreenl.构建pLVX-Wnt3a-IRES-Zs-Greenl慢病毒重组质粒,通过瞬时转染法包装出病毒上清,感染NSCs,设为Wnt3a-NSCs组;同时设GFP感染NSCs组(GFP-NSCs组)和未感染NSCs组(NSCs组)作为对照.免疫荧光染色法对Wnt3a-NSCs组NSCs进行nestin鉴定;Real-Time PCR检测各组细胞mWnt3a mRNA的表达;Western blotting检测各组细胞mWnt3a、β-catenin蛋白的表达.结果 经限制性内切酶检测、基因测序和绿色荧光观察证实成功构建了携带mWnt3a基因的重组慢病毒,且慢病毒滴度达3×108TU/mL.Wnt3a-NSCs组NSCs在荧光显微镜下证实有绿色荧光,且nestin表达阳性.Real-Time PCR和Western blotting结果显示感染后7d,Wnt3a-NSCs组mWnt3a mRNA和蛋白以及β-catenin蛋白均明显高于GFP-NSCs组和NSCs组(P＜0.01).结论 成功构建了表达mWnt3a基因的慢病毒载体,在体外培养条件下可以成功转染NSCs.     

Wnt3a影响神经干细胞分化的体外研究

目的探讨Wnt3a对胚胎大鼠海马神经干细胞（NSCs）体外分化的影响。方法采用机械分离、无血清传代培养法从胎鼠海马中获得NSCs,使用免疫荧光法对其干细胞特性及其受体Fzd3蛋白表达进行鉴定,观察Wnt3a对NSCs体外分化的影响。结果海马NSCs表达特异性标志物巢蛋白及胞膜蛋白Fzd3;体外诱导分化,Wnt3a处理组神经元及星形胶质细胞分化的比例分别为11．25％±0．62％和56．26％±4．82％,而对照组则为8．54％±0．48％和168．42％±5．54％;组间分化差异具有统计学意义（P〈0．05）。结论体外环境下Wnt3a能够促进NSCs向神经元分化,并抑制其向星形胶质细胞分化。     

经皮脊柱内镜完全可视化椎间孔成形术治疗腰椎间盘突出症的短期疗效

目的探讨经皮脊柱内镜完全可视化椎间孔成形技术治疗腰椎间盘突出症的短期疗效。方法回顾性分析2016年6月至2018年12月复旦大学附属闵行医院神经外科(18例)和复旦大学附属中山医院神经外科(14例)采用经皮脊柱内镜完全可视化椎间孔成形技术治疗的32例腰椎间盘突出症患者的临床资料。术后复查腰椎MRI,并行疼痛视觉模拟评分(VAS)、日本骨科协会(JOA)腰椎评分及Oswestry功能障碍指数(ODI)评估疗效。对所有患者行门诊随访,随访内容包括VAS、JOA评分、ODI评估及改良MacNab疗效评估。结果32例患者均顺利完成手术,术后均未出现感染、椎管内血肿及神经功能障碍。术后复查腰椎MRI显示突出的髓核摘除基本满意。与术前比较,32例患者术后2 d的VAS评分[分别为(2.21±1.18)分、(6.25±1.46)分]和ODI[(30.28±7.42)%、(68.63±11.04)%]均下降(均P<0.001),JOA评分升高[分别为(16.66±1.58)分、(12.43±1.85)分,P<0.001]。32例患者的随访时间为(15±5)个月(10~20个月)。随着随访时间的推移,32例患者的疼痛VAS评分呈下降趋势、JOA评分呈上升趋势、ODI呈下降趋势(F值分别为187.43、72.54、564.38,均P<0.001)。术后12个月随访时,32例患者的改良MacNab疗效评定结果为,优20例、良9例、可2例、差1例;优良率为90.6%(29/32)。结论经皮脊柱内镜完全可视化椎间孔成形技术治疗腰椎间盘突出症可改善疼痛和神经功能,帮助患者恢复生活和工作,短期疗效较好,远期效果需进一步随访观察。     

基质细胞衍生因子-1对神经干细胞的趋化作用

目的 观察基质细胞衍生因子-1(SDF-1)对神经干细胞(NSCs)迁移的影响.方法 由GFP转基因SD大鼠胚胎脑组织获取NSCs并进行传代培养,免疫细胞化学染色法检测SDF-1特异性受体CXCR4的表达,利用Blind-Well小室体外迁移体系观察不同浓度的SDF-1(0、1、10、50、100、500、1000μg/L)对NSCs定向迁移数量的影响,随后分别使用CXCR4激动剂和阻断剂处理NSCs,再次利用上述方法观察最适浓度SDF-1时NSCs的迁移.结果 成功分离培养得到能够稳定表达GFP的NSCs,且CXCR4在该种NSCs上有表达.体外趋化实验结果表明,SDF-1对NSCs有较强的趋化作用,随着SDF-1浓度的升高,发生迁移的细胞数量也随之增加,并于SDF-1浓度为500μg/L时达到最高峰;CXCR4特异性激动剂和阻断剂分别能够增强和减弱SDF-1对NSCs定向迁移的趋化作用.结论 SDF-1与其特异性受体CXCR4相互作用,能够对NSCs的定向迁移产生靶向性作用.     

小鼠pLVX-Wnt3a-IRES-ZsGreen1慢病毒载体的构建及神经干细胞转染

目的 构建共表达小鼠Wnt3a（mWnt3a）与绿色荧光蛋白(GFP)慢病毒载体,感染神经干细胞(NSCs),观察mWnt3a在NSCs中的表达。方法 利用同源重组技术将mWnt3a基因插入慢病毒载体pLVX-IRES-ZsGreen1,构建pLVX-Wnt3a-IRES-ZsGreen1慢病毒重组质粒,通过瞬时转染法包装出病毒上清,感染NSCs,设为Wnt3a-NSCs组;同时设GFP感染NSCs组（GFP-NSCs组）和未感染NSCs组(NSCs组)作为对照。免疫荧光染色法对Wnt3a-NSCs组NSCs 进行nestin鉴定;Real-Time PCR检测各组细胞mWnt3a mRNA的表达;Western blotting检测各组细胞mWnt3a、β-catenin蛋白的表达。结果 经限制性内切酶检测、基因测序和绿色荧光观察证实成功构建了携带mWnt3a基因的重组慢病毒,且慢病毒滴度达3×108 TU/mL。Wnt3a-NSCs组NSCs在荧光显微镜下证实有绿色荧光,且nestin表达阳性。Real-Time PCR和Western blotting结果显示感染后7 d, Wnt3a-NSCs组mWnt3a mRNA和蛋白以及β-catenin蛋白均明显高于GFP-NSCs组和NSCs组（P<0.01）。结论 成功构建了表达mWnt3a基因的慢病毒载体,在体外培养条件下可以成功转染NSCs。     

视神经部分损伤后视网膜基质细胞衍生因子-1α表达的变化

目的 研究大鼠视神经部分损伤后视网膜基质细胞衍生因子-1α(SDF-1α)的表达变化.方法 制作大鼠视神经部分损伤模型,于损伤后1、2、3、5、7、10、14 d收集视网膜组织,采用酶联免疫吸附法和实时荧光定量PCR分别测定损伤组(n=28)、假手术组(n=28)和正常对照组(n=12)大鼠视网膜组织中的SDF-1α蛋白及mRNA的表达.结果 视神经损伤后各时间点,损伤组视网膜组织中SDF-1α蛋白和mRNA的表达较假手术组及正常对照组均明显升高(P<0.01),均在损伤后第5天出现峰值.伤后14 d,损伤组视网膜组织中SDF-1α蛋白及mRNA仍维持在高表达状态.结论 视神经部分损伤后SDF-1α在视网膜中的表达出现上调,并可在较长时间内维持高表达.     

静脉性脑梗死

静脉性脑梗死（cerebral venous infarction,CVI）是指静脉性因素导致脑组织缺血、缺氧而发生坏死、出血、软化。形成梗死灶的一类疾病。CVI的病因复杂,临床表现多样且无特异性,既往对该病的诊断非常困难,预后不佳。随着对脑静脉系统功能认识的逐步提高及先进诊断技术的应用,该病的重要性愈来愈引起研究人员的重视。     

基质细胞衍生因子-1对神经干细胞的趋化作用

Objective To investigate the effect of stromal cell derived factor-1 ( SDF-1) on the regulation of neural stem cells (NSCs) migration. Methods NSCs were obtained from the cerebral cortex of embryonic GFP transgenic rats. After cell cultured in vitro, CXCR4, specific receptor of SDF-1, was detected by fluorescence immunocytochemistry. Using Blind-Well chambers, the chemotactic effects of SDF-1 was investigated by counting the cells which had crossed 8μm pore membrane and adhered to the superficies inferia of the membrane when confronted with varying concentrations of SDF-1α (0, 1, 10, 50, 100, 500 and 1000 μg/L) and the agonist or antagonist of CXCR4. Results Neurospheres were formed, which expressed GFP and were capable of differentiating into neurons (β-tubulin + ) and astrocytes (GFAP + ) in media without mitogens. Fluorescence immunocytochemistry showed that CXCR4 and Nestin were co-expressed in NSCs. SDF-1 showed great chemotaxis to NSCs, and the amount of cells migrating through the membrane in 500 μg/L SDF-1 group was more than that in other groups (P < 0. 05). The number of cells crossing the membrane could be augmented and diminished by the agonist and antagonist of CXCR4 respectively. Conclusion SDF-1 binding to its specific receptor CXCR4 was capable of inducing NSCs migrating directionally to the source of SDF-1.