论文部分内容阅读
目的:寻找一种转染效率高,细胞毒性低的非病毒基因载体,研究以人体内源性精胺为单体,以乙二醇二氯甲酸酯作为连接剂,以聚乙二醇(PEG)作为亲水基团连接剂合成亲水修饰聚阳离子载体PEG-Polycarbam-SP的基因担载效率,以及对非洲绿猴肾癌细胞COS-7的转染活性和细胞毒性的影响。方法:琼脂糖凝胶电泳方法考察复合物的基因担载效率,检测基因复合物的粒径和电位,以荧光素酶质粒为报告基因,研究PEG-Polycarbam-SP/DNA的复合物在COS-7细胞的转染活性,用MTT方法研究PEG-Polycarbam-SP对COS-7细胞的毒性。结果:聚合物与质粒在质量比5以后形成的复合物粒径稳定在50nm左右,Zate电位在20mV左右。COS-7细胞实验显示PEG-Polycarbam-SP具有低于PEI 25kDa的细胞毒性,同时也具有高效输送DNA的能力。结论:PEG-Polycarbam-SP是一种新型的高效、低毒,在基因治疗领域有潜在应用价值的非病毒基因输送载体。
OBJECTIVE: To find a non-viral gene vector with high transfection efficiency and low cytotoxicity. To study the effect of human spermine as monomer, ethylene glycol bischloroformate as linker and polyethylene glycol ( PEG) as a hydrophilic group linker to PEG-Polycarbam-SP, and its effect on the transfection activity and cytotoxicity of COS-7 in African green monkey kidney cancer cells. METHODS: The efficiency of gene-loading of the complex was investigated by agarose gel electrophoresis. The particle size and potential of the complex were detected. Luciferase reporter plasmid was used to study the effect of PEG-Polycarbam-SP / DNA complex on COS- 7 cells, MTT assay was used to study the toxicity of PEG-Polycarbam-SP to COS-7 cells. Results: The particle size of polymer and plasmid formed after mass ratio of 5 was about 50nm and the Zate potential was about 20mV. COS-7 cell experiments show that PEG-Polycarbam-SP has a cytotoxicity of 25 kDa lower than that of PEI, as well as its ability to efficiently deliver DNA. Conclusion: PEG-Polycarbam-SP is a novel non-viral gene delivery vector with high potency, low toxicity and potential application in the field of gene therapy.