目的探讨低频聚焦超声辐照携载腺病毒靶向微泡增强基因转染颅内胶质瘤的效果。方法原位接种U251胶质瘤细胞制备小鼠颅内胶质瘤模型25只;制备可以携载腺病毒载体和偶联RGD肽的脂质体微泡,并检测其性状。筛选颅内胶质瘤直径3.0~4.0 mm的小鼠分为3组,Ⅰ组注射未携带腺病毒的非靶向微泡(对照组),Ⅱ组注射载腺病毒的非靶向微泡,Ⅲ组注射载腺病毒的靶向微泡,各组注射微泡后均接受超声辐照,频率1 MHz,强度0.7 W/cm2,时间5 min;使用小动物活体荧光成像系统观察各组小鼠颅内荧光强度。结果制备的脂质体微泡直径为1.10~1.20 μm,平均浓度(7.8±0.43)×108/ml,其可携带腺病毒,还可偶联RGD肽。MRI筛选颅内肿瘤直径3.0~4.0 mm的荷瘤小鼠15只,分为3组(每组5只),小动物活体荧光成像显示,与Ⅰ组和Ⅱ组比较,Ⅲ组小鼠颅内荧光强度显著增强(均P<0.01)。结论静脉注射偶联RGD肽的载腺病毒靶向微泡可以将携载的目的基因有效地转染至颅内胶质瘤,为胶质瘤的基因治疗提供了一种新思路。
Objective To explore the transfection efficiency of adenovirus-targeted microbubbles enhanced report gene in intracranial glioma by low frenquency focused ultrasound irritation. Methods Intracranial glioma models were prepared by transplanting U251 glioma cells in 25 mice. Liposome microbubbles carrying adenovirus vector and RGD peptide were prepared and their properties were detected. Fifteen mice of intracranial glioma model were selected and randomly divided into three groups with 5 mice in each group. The animals in group Ⅰ were injected untargeted microbubbles without carrying adenovirus,the ones in groupⅡ were injected untargeted microbubbles carrying adenovirus,the ones in group Ⅲ were injected targeted microbubbles carrying adenovirus,all three groups were irriated by ultrasound(1 MHz,0.7 W / cm2,5 min). The intracranial fluorescence intensity in three groups was observed and analyzed by small animal in vivo fluorescence imaging system.Results The diameter of liposome microbubbles was about 1.10~1.20 μm,and the average concentration was about (7.8±0.43)×108/ml,these microbubbles could carry adenovirus and coulpe RGD peptide. 15 mice with glioma diameter 3.0~4.0 mm were selected by MRI,then divided into 3 groups(each group has 5 mice).In vivo fluorescence imaging of small animals showed that the intracranial fluorescence intensity of group Ⅲ mice was significantly increased compared with groupⅠ and group Ⅱ(P<0.01).Conclusion Intravenous injection of adenovirus-targeted liposome microbubbles coupled with RGD peptide can effectively transfect the target gene into intracranial glioma,which provides a new idea for gene therapy of glioma.
Journal of Ultrasound in Clinical Medicine
Low frequency focused ultrasound