Liang Wenqing, Gong Haiyang, Yin Dongfeng, Lu Shiyong, Fu Qiang
Department of Orthopaedics, Shaoxing People's Hospital, China.
Chem Pharm Bull (Tokyo). 2011;59(9):1094-101. doi: 10.1248/cpb.59.1094.
In order to enhance the gene delivery efficiency and decrease cytotoxicity of polyplexes, copolymers consisting of branched polyethyleneimine (PEI) 25 kDa grafted with Pluronic (F127, F68, P105) were successfully synthesized using a simple two-step procedure. The copolymers were tested for cytotoxicity and DNA condensation and complexation properties. Their polyplexes with plasmid DNA were characterized in terms of DNA size and surface charge and transfection efficiency. The complex sizes were below 300 nm, which implicated their potential for intracellular delivery. The Pluronic-g-PEI exhibited better condensation and complexation properties than PEI 25 kDa. The cytotoxicity of PEI was strongly reduced after copolymerization. The Pluronic-g-PEI showed lower cytotoxicity in three different cell lines (Hela, MCF-7, and HepG2) than PEI 25 kDa. pGL3-lus was used as a reporter gene, and the transfection efficiency was in vitro measured in HeLa cells. Compared with unmodified PEI 25 kDa Pluronic-g-PEI showed much higher transfection efficiency. These results demonstrate that polyplexes prepared using a combined strategy of surface crosslinking and grafted with Pluronic seem to provide promising properties as stable, high transfection efficiency vectors.
为了提高基因传递效率并降低多聚体的细胞毒性，采用简单的两步法成功合成了由接枝有普朗尼克（F127、F68、P105）的25 kDa支化聚乙烯亚胺（PEI）组成的共聚物。对这些共聚物进行了细胞毒性、DNA凝聚和络合特性测试。对它们与质粒DNA形成的多聚体进行了DNA大小、表面电荷和转染效率方面的表征。复合物大小低于300 nm，这暗示了它们在细胞内递送方面的潜力。接枝有普朗尼克的PEI（Pluronic-g-PEI）比25 kDa的PEI表现出更好的凝聚和络合特性。共聚后，PEI的细胞毒性大幅降低。在三种不同细胞系（Hela、MCF-7和HepG2）中，Pluronic-g-PEI比25 kDa的PEI表现出更低的细胞毒性。使用pGL3-luc作为报告基因，在HeLa细胞中体外测量转染效率。与未修饰的25 kDa PEI相比，Pluronic-g-PEI表现出更高的转染效率。这些结果表明，采用表面交联和接枝普朗尼克的组合策略制备的多聚体似乎具有作为稳定、高转染效率载体的良好特性。
