Development of novel gene delivery vector using oligo-arginine lipids

基因治疗的成功依赖于使用非病毒载体的基因递送系统，该系统具有高转染效率和低毒性，本研究合成了寡聚精氨酸结合脂质（oligoarginine conjugated-lipid，Arg），制备了两种Arg基微粒; Arg缀合的脂质与质粒DNA的复合物（Arg/DNA），和用鱼精蛋白压实的Arg缀合的脂质包被的质粒DNA（ArgPD），优化了质粒DNA与载体DNA的电荷比（+/-），发现Arg 10偶联脂质载体（Arg 10 conjugated-lipid vector，Arg 10 PD）能有效地转染基因，尤其是带正电荷的Arg 10 PD。在肿瘤内注射转染中，带负电的粒子比带正电的粒子表现出更高的转染效率。在Arg 4PD和Arg 10 PD中，Arg 4PD的转染效率是Arg 10 PD的13倍。这表明较短的寡聚精氨酸长度对于肿瘤内基因递送是有效的。Arg 4偶联脂质具有作为瘤内注射非病毒载体的潜力。Arg 4和Arg 10载体的基因转移机制不同。前者通过内吞作用进入，后者通过巨胞饮作用进入。

The success of gene therapy is depended on gene delivery system using non-viral vector with high transfection efficiency and less toxicity.In this study, we synthesized oligoarginine conjugated-lipid (Arg), developed two kinds of Arg based particles; Arg conjugated-lipid complex with plasmid DNA (Arg/DNA), and Arg conjugated-lipid coating plasmid DNA compacted with protamine (ArgPD), and optimized the charge ratio (+/-)of vector and plasmid DNA in human cervical carcinoma HeLa cells and tumor via intratumoral transfection.The transfection efficiencies in HeLa cells resulted in efficient DNA transfer when arginine 10 conjugated-lipid vector (Arg10) effectively transfected gene, especially positive-charged Arg10PD. In tumor transfection by intratumoral injection, negative-charged particles showed higher transfection efficiency compared with positive-charged ones. In Arg4PD and Arg10PD with similar negative-charged, Arg4PD showed 13-fold higher transfection efficiency than Arg10PD. This suggested that shorter oligoarginine length is effective for intratumoral gene delivery. Arg4 conjugated-lipid has a potential of non-viral vector for intratumoral injection. The mechanism of gene transfer by Arg 4 and Arg10 vectors was different. The former was penetrated via endocytosis and the latter was via macropinocytosis.