Degradable polyethylenimine-alt-poly(ethylene glycol) copolymers as novel gene carriers
Degradable polyethylenimine-alt-poly(ethylene glycol) copolymers as novel gene carriers
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DOI：
10.1016/j.jconrel.2005.04.008
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发表时间：
2005-07-20
影响因子：
10.8
通讯作者：
Cho, CS
中科院分区：
文献类型：
--
作者：
Park, MR;Han, KO;Cho, CS
一个理想的基因载体既要安全又要有转染效率。聚乙烯亚胺（PEI）是一种阳离子聚合物，由于其缓冲能力而具有高转染效率。但据报道，PEI在许多细胞系中具有细胞毒性且不可降解。在这项研究中，我们合成了可降解的PEI-alt-聚（乙二醇）（PEG）共聚物作为一种新的基因载体，利用迈克尔型加成反应，并进行了表征。这些共聚物与质粒DNA复合，并通过动态光散射，凝胶阻滞和原子力显微镜，以确定颗粒大小，复合物的形成和复杂的形状，分别得到的复合物进行了表征。在培养的HeLa人宫颈上皮癌细胞、HepG 2人肝母细胞瘤细胞系和MG 63人骨肉瘤细胞中也检查了共聚物的细胞毒性和转染效率。共聚物中PEG与PEI的比率接近1，共聚物的分子量范围为约8000至12，900。这些共聚物在37 ℃下在0.1M磷酸盐缓冲盐水（PBS，pH 7.4）中快速降解。以12的N/P比形成完整的共聚物/DNA复合物，产生抗DNA酶I的复合物。粒径随着N/P比和PEG分子量的增加而减小，在PEI-alt-PEG（700）的N/P比为45时表现出75 nm的最小值。细胞毒性研究表明，即使在高共聚物浓度下，共聚物也没有表现出细胞毒性作用。此外，转染效率受PEG分子量的影响，并且在PEI-alt-PEG（258）的情况下，在HepG 2和MG 63中的转染效率高于PEI 25 K，而在HeLa细胞中低于PEI 25 K。(c)2005 Elsevier B. V.保留所有权利。
An ideal gene carrier requires both safety and transfection efficiency. Polyethylenimine (PEI) is a well-known cationic polymer, which has high transfection efficiency owing to its buffering capacity. But it has been reported that PEI is cytotoxic in many cell lines and non-degradable. In this study, we synthesized degradable PEI-alt-poly(ethylene glycol) (PEG) copolymers using Michael-type addition reactions as a new gene carrier and characterized them. These copolymers were complexed with plasmid DNA and the resulting complexes were characterized by dynamic light scattering, gel retardation and atomic force microscopy to determine particle sizes, complex formation and complex shape, respectively. Cytotoxicity and transfection efficiency of the copolymers were also checked in cultured HeLa human cervix epithelial carcinoma cells, HepG2 human hepatoblastoma cell line and MG63 human osteosarcoma cells. PEG to PEI ratio in the copolymers was near I and the molecular weight of the copolymer ranged from around 8000 to 12,900. These copolymers degraded rapidly at 37 degrees C in 0.1 M phosphate buffered saline (PBS, pH 7.4). The complete copolymer/DNA complex was formed at an N/P ratio of 12, producing a complex resistant to DNase I. Particle sizes decreased with increasing N/P ratio and PEG molecular weight, exhibiting a minimum value of 75 nm at an N/P ratio of 45 with PEI-alt-PEG (700). Cytotoxicity study showed that copolymers exhibited no cytotoxic effects on cells even at high copolymer concentration. Also, transfection efficiency was influenced by PEG molecular weight and, in case of PEI-alt-PEG (258), the transfection efficiency was higher than that for PEI 25 K in HepG2 and MG63, whereas it was lower than that for PEI 25K in HeLa cells. (c) 2005 Elsevier B.V. All rights reserved.