【摘要】 目的　制备壳聚糖脱氧核糖核酸 (DNA)纳米球并研究其理化性质和转染肝细胞系HepG2和L 0 2的活性。方法　用绿色荧光蛋白 (GFP)质粒做报告基因 ,GFP和壳聚糖通过复凝聚方法制备壳聚糖DNA纳米球 ,用扫描电镜观察其形态 ,激光粒度分析仪测定壳聚糖DNA纳米球粒度分布、表面电位 ,DNaseⅠ保护实验研究壳聚糖DNA纳米球对包裹基因的保护作用 ,用体外基因转染实验定性评价纳米球的转染活性 ,MTT试验研究壳聚糖DNA纳米球对HepG2和L 0 2的细胞毒作用。结果　壳聚糖形成表面带正电荷的纳米球 ,保护DNA免受DNaseⅠ的降解。壳聚糖DNA纳米球作为非病毒载体转染肝细胞系 ,基因能有效表达。结论　壳聚糖DNA纳米球作为非病毒载体转染肝细胞系有效 ,壳聚糖转染有细胞选择性。更多还原

【Abstract】 Objective To study the preparation and characteristics of chitosan DNA nanoparticles and their activities in the transfection of HepG2 and L-02 liver cell lines. Methods Chitosan DNA nanoparticles were prepared by a complex coacervation of chitosan and GFP, the latter acting as the reporter gene. The appearance of the nanoparticles was surveyed with the scanning electron microscope. The grain distribution and zeta potentials of the nanoparticles were determined with the laser grain analyzer. DNase Ⅰassay was used to study the gene protection effect of the nanoparticles. The transfection activities of the chitosan- plasmid nanoparticles were qualitatively assessed by an in vitro gene transfection test. The cytotoxity of the nanoparticles to HepG2 and L-02 cell lines was examined with the MTT assay. Results Positive charges formed by chitosan on the nanoparticles protected the DNA from degradation by DNase Ⅰ, Genes were effectively expressed by the liver cell lines when the latter were transfected by chitosan DNA nonaparticles as non-viral vector. The transfection efficiency of L-02 cells was strikingly higher than that of Hep G2 cells. Conclusion As non-viral vector, chitosan nanoparticles were shown to transfect liver cell lines effectively. Chitosan transfection was also shown to have a cell selectivity. The nanoparticles showed no cytotoxicity to the liver cell lines.更多还原