Sustained delivery and expression of DNA encapsulated in polymeric nanoparticles
Sustained delivery and expression of DNA encapsulated in polymeric nanoparticles
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DOI：
10.1038/sj.gt.3301318
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发表时间：
2000-11-01
期刊：
影响因子：
5.1
通讯作者：
Golomb, G
中科院分区：
文献类型：
--
作者：
Cohen, H;Levy, RJ;Golomb, G
缓释聚合物基因传递系统提供了增加的抗核酸酶降解，质粒DNA （pDNA）摄取量的增加，以及控制pDNA给药剂量和持续时间的可能性。此外，这种系统缺乏与病毒载体相关的固有问题。采用可生物降解和生物相容性的聚乳酸-羟基乙酸酯（DL-lactide-co-glycolide）聚合物将报告基因pDNA （alkaline phosphatase， AP）包封在亚微米大小的颗粒中。在体外和体内评估了纳米颗粒（NP）介导的基因表达与阳离子脂质体传递的比较。制备了具有高包封率（70%）的聚（dl -丙交酯-共聚物）聚合物颗粒，并在600 nm的纳米范围内负载pDNA， pDNA缓释超过一个月。捕获的质粒保持了其结构和功能的完整性。体外转染pDNA- np后，其表达水平明显高于裸pDNA。此外，随着转染时间的延长，AP水平升高，表明pDNA持续活跃。然而，与标准脂质体转染相比，基因表达明显降低。在大鼠体内注射7天后，发现裸pDNA和pDNA- np的效力明显高于脂质体pDNA（1-2个数量级）。质粒DNA-NP处理后7天和28天AP表达增加，表明NP具有持续活性。
Sustained release polymeric gene delivery systems offer increased resistance to nuclease degradation, increased amounts of plasmid DNA (pDNA) uptake, and the possibility of control in dosing and sustained duration of pDNA administration. Furthermore, such a system lacks the inherent problems associated with viral vectors. Biodegradable and biocompatible poly(DL-lactide-co-glycolide) polymer was used to enacapsulate pDNA (alkaline phosphatase, AP, a reporter gene) in submicron size particles. Gene expression mediated by the nanoparticles (NP) was evaluated in vitro and in vivo in comparison to cationic-liposome delivery. Nano size range (600 nm) pDNA-loaded in poly(DL-lactide-co-glycolide) polymer particles with high encapsulation efficiency (70%) were formulated, exhibiting sustained release of pDNA of over a month. The entrapped plasmid maintained its structural and functional integrity. In vitro transfection by pDNA-NP resulted in significantly higher expression levels in comparison to naked pDNA. Furthermore, AP levels increased when the transfection time was extended, indicating sustained activity of pDNA. However, gene expression was significantly lower in comparison with standard liposomal transfection. Seven days after i.m. injections in rats, naked pDNA and pDNA-NP were found to be significantly more potent (1-2 orders of magnitude) than liposomal pDNA. Plasmid DNA-NP treatment exhibited increased AP expression after 7 and 28 days indicating sustained activity of the NP.