Targeted minicircle DNA delivery using folate-poly(ethylene glycol)-polyethylenimine as non-viral carrier.
Targeted minicircle DNA delivery using folate-poly(ethylene glycol)-polyethylenimine as non-viral carrier.
复制标题
DOI：
10.1016/j.biomaterials.2010.04.042
复制
发表时间：
2010-08
期刊：
影响因子：
14
通讯作者：
Chao Zhang;Shijuan Gao;Wei Jiang;Song Lin;F. Du;Zi‐Chen Li;Wenlin Huang
中科院分区：
文献类型：
--
作者：
Chao Zhang;Shijuan Gao;Wei Jiang;Song Lin;F. Du;Zi‐Chen Li;Wenlin Huang
靶向基因递送系统由于其将治疗基因引导至靶细胞的潜力而引起了极大的关注。然而，由于其效率低，聚合物载体的大多数成功应用都集中在能够实现稳健表达的基因上。小环 DNA (mcDNA) 是改善基因表达和延长基因表达寿命的有力候选者。在这项研究中，我们将叶酸/聚乙二醇修饰的聚乙烯亚胺和mcDNA结合起来作为一种新的肿瘤基因递送系统。我们发现叶酸标记的复合物是均质的，尺寸范围为 60 至 85 nm。在叶酸受体阳性细胞中，mcDNA 将基于叶酸标记载体的基因表达提高了 2-8 倍。叶酸竞争测定结果表明，叶酸标记载体介导的mcDNA通过受体介导的内吞作用内化至细胞内。对聚合复合物内吞途径的研究表明，它们的大部分从内/溶酶体中逃逸，并且聚合复合物在细胞核中分离之前是相关联的。此外，体内光学成像和荧光素酶测定表明，叶酸标记的复合物的全身递送导致转基因在叶酸受体阳性肿瘤中优先积累，并且mcDNA介导的方法在肿瘤中实现了比传统质粒高2.3倍的基因表达。细胞毒性测定表明，聚乙二醇屏蔽可降低 PEI 的毒性。
Targeted gene delivery systems have attracted great attention due to their potential in directing the therapeutic genes to the target cells. However, due to their low efficiency, most of the successful applications of polymeric vectors have been focused on genes which can achieve robust expression. Minicircle DNA (mcDNA) is a powerful candidate in terms of improving gene expression and prolonging the lifespan of gene expression. In this study, we have combined folate/poly(ethylene glycol) modified polyethylenimine and mcDNA as a new tumor gene delivery system. We found that folate-labeled polyplexes were homogenous, with a size ranging from 60 to 85 nm. mcDNA increased folate-labeled vector based gene expression 2–8 fold in folate receptor-positive cells. Results of folic acid competition assay indicated that mcDNA mediated by folate-labeled vector were internalized into cells through receptor-mediated endocytosis. The investigation of the endocytosis pathway of the polyplexes showed that a large portion of them escaped from endo/lysosome and the polyplexes were associated before being separated in the nucleus. Furthermore, in vivo optical imaging and luciferase assays demonstrated that systemic delivery of the folate-labeled polyplexes resulted in preferential accumulation of transgenes in folate receptor-positive tumors, and mcDNA mediated approach achieved 2.3 fold higher gene expressions in tumors than conventional plasmid. Cytotoxicity assays showed that PEG-shielding of the polyplexes reduced the toxicity of PEI.