Development of novel gene delivery vector using oligo-arginine lipids

基因治疗的成功取决于采用转染效率高、毒性小的非病毒载体的基因传递系统。本研究合成了低精氨酸共轭脂质（Arg），开发了两种基于Arg的颗粒；采用精氨酸偶联脂质复合物与质粒DNA （Arg/DNA）、精氨酸偶联脂包覆质粒DNA与鱼精蛋白压实（ArgPD），通过瘤内转染优化了载体与质粒DNA在人宫颈癌HeLa细胞和肿瘤中的电荷比（+/-）。在HeLa细胞中，精氨酸10共轭脂质载体（Arg10）有效转染基因，特别是带正电荷的Arg10PD，转染效率高，DNA转移效率高。在瘤内注射转染肿瘤时，负电荷粒子的转染效率高于正电荷粒子。在具有相似负电荷的Arg4PD和Arg10PD中，Arg4PD的转染效率比Arg10PD高13倍。这表明较短的低精氨酸长度对肿瘤内基因传递是有效的。Arg4偶联脂质具有作为肿瘤内注射的非病毒载体的潜力。arg4和Arg10载体的基因转移机制不同。前者通过内吞作用穿透，后者通过巨噬细胞作用穿透。

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.