Enhancement of gene transfection to muscle cell combining ultrasound-targeted microbubble destruction with polyethyleneimine: an in vivo study / 中华超声影像学杂志

ABSTRACT

Objective To investigate the effect of gene transfection to mice's muscle combining polyethyleneimine (PEI) with ultrasound (US)-targeted microbubble (MB) destruction (UTMD).Methods Twenty-five female Balb/c mice were divided into 5 groups (5 mice per group) randomly.Plasmid DNA (20 μg) encoding green fluorescent protein (GFP) was used as expresion vector.The transfection materials were injected into the bilateral tibialis anterior muscles of mice respectively and delivered as follows(a) untreated control,(b) plasmid + US,(c) plasmid + US + MB,(d) plasmid + PEI,(e) plasmid + PEI + US,(f) plasmid + PEI + MB+ US.SonoVue MB was used at a final concentration of 30％ (v/v).The acoustic intensity and duty cycle were optimized before the study and set at 2.0 W/cm2 and 50％ respectively.Transfection efficiency was assessed by counting the number of GFP-positive fibers under fluorescence microscopy 10 days after gene delivery.Hematoxylin-Eosin staining was performed on separate specimen and examined with light microscopy for tissue damage.Results No GFP-positive fiber was found in the untreated control group.There were 14 ± 3,58 ± 6,96 ± 7,119 ± 11 and 158 ± 18 GFP-positive fibers respectively found in plasmid+ US,plasmid + MB + US,plasmid + PEI,plasmid + PEI + US,and plasmid + PEI + MB + US groups.The plasmid + PEI + MB + US group had the maximal GFP-positive fibers,the differences were significant compared with other groups (P ＜0.05).No evidence of inflammation or necrosis was revealed in histological examination with hematoxylin-eosin staining.Conclusions PEI combining with UTMD can significantly improve efficiency of gene transfection in vivo and has great potential in gene therapy.