绿色荧光蛋白基因腺病毒载体转染兔骨髓间充质干细胞的实验

背景:以骨髓间充质干细胞作为种子细胞,把干细胞和基因治疗结合起来是研究中枢神经系统损伤和肿瘤治疗新的思路和趋势.目的:观察腺病毒载体绿色荧光蛋白基因(Ad-GFP)在兔骨髓问充质干细胞转染和表达的量效关系及对细胞生物学特性的影响,探讨用该载体构建基因修饰骨髓间充质干细胞的可行性.设计、时间及地点:随机分组设计,对比观察,于2008-08/2009-03在南方医科大学完成.材料:新西兰大白兔,雌雄不拘,质量2.0-3.0 kg.方法:体外分离培养兔骨髓间充质干细胞,流式细胞仪检测细胞免疫表型,293细胞包装制备病毒,以不同滴度的Ad.GFP(1×10~3～1×10~(10)PFU/mL)转染骨髓间充质干细胞,细胞计数法分析转染率.主要观察指标:倒置显微镜观察细胞形态学改变,CCK8法检测细胞增殖活性,用血清撤离加入β-巯基乙醇诱导感染Ad-GFPBMSCs向神经样细胞的定向分化.结果:3-6代骨髓间充质干细胞表面标志CD34、CD45阴性,而CD29、CD44阳性.当病毒滴度为1×10~7PFU/mL时感染率为55%,1×10~9,1 ×10~(10)PFU/mL感染率均为85%,但1×10~(10)PFU/mL时出现细胞病理现象,7 d荧光表达最强,28 d仍可见荧光表达.感染Ad-GFP的骨髓间充质干细胞经β-巯基乙醇诱导可分化为神经元样细胞,神经元特异性烯醇化酶表达阳性.结论:合适滴度的Ad-GFP可以高效感染骨髓间充质干细胞,对细胞的生物学特性影响较小,不影响诱导分化功能,骨髓间充质干细胞可以作为Ad-GFP载体系统进行基因治疗研究的种子细胞.

Transfection of rabbit bone marrow mesenchymal stem cells with adenovirus vector carrying green fluorescent protein

BACKGROUND: It is a new tendency to treat central nervous system injury or tumor therapy using the combination of seed cells and gene therapy.OBJECTIVE: To observe the dose-relationship between transfection and expression of rabbit bone marrow mesenchymal stem cell (BMSCs) with adenovirus vector carrying green fluorescent protein (Ad-GFP), and to study its effects on cell biological properties, in addition, to explore the feasibility of using Ad-GFP vector to construct gene modified BMSCs.DESIGN, TIME AND SETTING: A randomized grouping, contrast observation. The experiment was performed at the Southern Medical University between August 2008 and March 2009.MATERIALS: New Zealand white rabbits, irrespective of genders, weighing 2.0-3.0 kg, were selected.METHODS: BMSCs were separated and cultured in vitro, and then the cell immunophenotypes were detected by flow cytometry.The adenovirus was obtained by packaging 293 cells and was used to transfect BMSCs with various liters (1 ×-10~3-1×10~(10) PFU/mL).Cytometry was used to analyze the transfection efficiency.MAIN OUTCOME MEASURES: Cell morphological changes were detected under an invert microscope. The cell proliferation was detected by CCK8 kits. BMSCs transfected with Ad-GFP were induced differentiating into neuron-like cells by adding of β-mercaptoethanol.RESULTS: The surface markers of 3-6-generation BMSCs were negative to CD34 and CD45, but positive for CD29 and CD44.When the virus titers were 1 ×10~7 PFU/mL, the transfection rate was 55%, which were 85% when the virus titers were 1 ×10~9 and1×10~(10) PFU/mL. However, cell pathology phenomenon occurred when the virus titer was 1 ×10~(10) PFU/mL. The fluorescence was strongest expressed at day 7, and it still can be seen at day 28. The BMSCs trasfected with Ad-GFP could differentiate into neuron-like cells under induction of p-mercaptoethanol, with positive neuron-specific enolase.CONCLUSION: Ad-GFP with suitable titers can infect BMSCs effectively with little influence on the biology property or differentiation function. BMSCs can serve as seeds cell in gene therapy field when utilizing ad-GFP vector system.