Shanghai East Hospital, The Institute for Biomedical Engineering and Nanoscience, Tongji University School of Medicine, Tongji University, Shanghai 200092, People's Republic of China.
Institute of Nanochemistry and Nanobiology, Shanghai University, Shanghai 200444, People's Republic of China.
Acta Biomater. 2015 Aug;22:120-30. doi: 10.1016/j.actbio.2015.04.025. Epub 2015 Apr 25.
The purpose of this study is to develop biodegradable cationic polyamides for non-viral gene delivery and elucidate their structural effects on gene transfection activity. To this end, a group of novel cationic polyamides were synthesized by polycondensation reaction between different di-p-nitrophenyl esters and tertiary amine-containing primary diamines. These linear polyamides have flexible alkylene group (ethylene or propylene), protonable amino group and bioreducible disulfide linkage in the polyamide main chain. The alkylene group and disulfide linkage in these polyamides have a distinct effect on their gene delivery properties including buffering capacity, gene binding ability and intracellular gene release profile. Those cationic polyamides containing disulfide linkage and 1,4-bis(3-aminopropyl)piperazine (BAP) residue exhibited high buffering capacity (endosomal escape ability), high gene binding ability, and intracellular gene release ability, thus inducing fast gene nucleus translocation and robust gene transfection in vitro against different cell lines and rat bone marrow mesenchymal stem cells. Moreover, the transfection efficiencies in vitro were comparable or higher than those of 25 kDa branched polyethylenimine and Lipofectamine 2000 transfection agent as positive controls. These cationic polyamides and their polyplexes were of low cytotoxicity when an optimal transfection efficacy was achieved. In vivo transfection tests showed that bioreducible BAP-based polyamides were applicable for intravenous gene delivery in a mouse model, leading to higher level of transgene expression in the liver as compared to 22 kDa linear polyethylenimine as a positive control. These cationic polyamides provide a useful platform to elucidate the relationship between chemical functionalities and gene transfection activity.
本研究旨在开发可生物降解的阳离子聚酰胺用于非病毒基因传递，并阐明其结构对基因转染活性的影响。为此，通过不同的二对硝基苯酯和含叔胺的伯二胺之间的缩聚反应合成了一组新型阳离子聚酰胺。这些线性聚酰胺在聚酰胺主链中具有柔性亚烷基（乙烯或丙烯）、质子化氨基和可生物还原的二硫键。这些聚酰胺中的亚烷基和二硫键对其基因传递性能具有明显的影响，包括缓冲能力、基因结合能力和细胞内基因释放谱。那些含有二硫键和 1,4-双(3-氨基丙基)哌嗪（BAP）残基的阳离子聚酰胺具有高缓冲能力（内涵体逃逸能力）、高基因结合能力和细胞内基因释放能力，从而诱导快速的基因核转位和在体外对不同细胞系和大鼠骨髓间充质干细胞的强大基因转染。此外，当达到最佳转染效果时，其体外转染效率可与 25 kDa 支化聚乙烯亚胺和 Lipofectamine 2000 转染试剂等阳性对照相当或更高。当达到最佳转染效率时，这些阳离子聚酰胺及其聚合物的细胞毒性较低。体内转染试验表明，可生物还原的 BAP 基聚酰胺可适用于小鼠模型中的静脉内基因传递，与作为阳性对照的 22 kDa 线性聚乙烯亚胺相比，可导致肝脏中转基因表达水平更高。这些阳离子聚酰胺为阐明化学功能与基因转染活性之间的关系提供了一个有用的平台。
