脂质体微泡对超声介导基因转染的增效作用研究

目的 探讨超声介导基因转染时,脂质体微泡(LM)对体内、外红色荧光蛋白基因(RFP)转染的增效作用及其安全性.方法将RFP和LM加入培养的Hela细胞后行超声辐照(US),对微泡浓度、超声强度、辐照时间进行优化研究,运用荧光显微镜、流式细胞术评估基因转染率,并对细胞损伤进行分析.在裸鼠移植瘤的体内实验中,将LM和RFP质粒(P)经尾静脉注入后予以超声辐照(P+LM+US),以单纯质粒注射(P)、P+US、P+LM作为对照,行冰冻切片,组织学检查,RFP表达检测.结果培养的Hela细胞经LM和超声辐照联合处理后,RFP基因转染率显著增加,差异有统计学意义(P＜0.01),在超声强度为1.0 W/cm2、微泡浓度为6%、辐照3 min的条件下最显著,且未发现显著的细胞损伤.P+LM+US组的裸鼠移植瘤内RFP表达显著高于P组、P+US组或P+LM组,差异均有统计学意义(P＜0.01),且未观察到明显的组织损伤.结论 LM对超声介导基因转染的体内、外转染效率有显著的增效作用,而无明显的细胞或组织损伤,为临床基因治疗提供一种新颖、高效、安全的非病毒基因转染方法.

The enhanced effects of liposome microbubble under ultrasound mediated gene transfection conditions

Objective To study the transfeetion efficiency and safety of liposome microbubble(LM)on red fluorescent protein(RFP)in vitro and in vivo under ultrasound mediated gene transfection(USMGT)conditions.Methods Plasmids containing RFP were added to cultured Hela cells followed by ultrasound (US)exposure with LM.Different concentration of LM,US intensity and exposure time were optimized.Transfection efficiency was evaluated by fluorescent microscopy and FACS.Cell viability was verified by propidium iodide assay.In transplanted tumors in vivo study,LM and plasmid(P)were injected into the nude mice followed by US exposure(P+LM+US group).Nude mice undergoing plasmid injection alone(P group),plasmid injection and US exposure(P+US group)and plasmid and LM injection(P+LM group)were used as controls.Frozen section and histological examination were conducted and RFP expression was evaluated.Results LM and US exposure significantly increased transfeetion efficiency in cultured Hela cells (P＜ 0.01).Transfection efficiency was the most prominent under the condition of US intensity of 1.0 W/cm2 with 6%LM,duration 3 min.No apparent cell damage was found in the all groups.In transplanted tumors,strong RFP was seen in P+LM+US group.It was significantly higher than in any other groups(P＜0.0 1).No tissue damage was seen histologically.Conclusions LM could enhance USMGT effectively without causing any apparently adverse effect in vitro and in vivo.This method would be a novel,effective,safe non-viral gene transfection method and provide an alternative to current clinical gene therapy.