小干扰RNA在小鼠体内的分布及对呼吸道合胞病毒的干扰效果

目的 观察小干扰RNA( siRNA) 7816在小鼠体内的分布及吸收情况,探讨siRNA7816对呼吸道合胞病毒(RSV)感染的抑制效果.方法 将5’端带有三氢吲哚氰( cy3)荧光基团的siRNA7816,通过滴鼻的方法散布到小鼠的肺组织中,并于滴鼻后的12h将小鼠处死,无菌条件下取小鼠肺组织、肝脏组织及肠组织,并迅速行组织冷冻切片,荧光显微镜下观察siRNA7816在Balb/c小鼠体内的分布情况.将48只Balb/c小鼠随机分为6组,每组8只,各组均予以1010 pfu·L-1的RSVA2标准株病毒行滴鼻处理,并于感染后的第2天分别予治疗组小鼠0.5 nmol、1.0 nmol及2.0 nmol的治疗量siRNA7816,阴性对照组则予以1.0 nmol的阴性siRNA,PBS组予PBS滴鼻处理,空白对照组不予任何处理.于感染后的第3天将小鼠处死,并于无菌条件下取小鼠肺组织,通过光学显微镜观察小鼠肺组织的病理改变和免疫组织化学检测光密度值的方法,了解siRNA7816对RSV病毒的抑制效果.结果 siRNA7816通过滴鼻的方法能够顺利到达Balb/c小鼠肺部,并分布于支气管、肺泡等处,且分布水平较高；病理结果显示siRNA7816能显著减轻RSV感染小鼠的炎症,免疫组织化学分析结果显示siRNA7816对RSV病毒蛋白的表达有抑制作用,与PBS组比较差异有统计学意义(P＜0.05).结论 采用滴鼻的方法可以将siRNA投送到小鼠肺组织的有效部位并形成一定浓度,siRNA7816对RSV的复制有一定抑制作用.

Distribution of Small Interference RNA and Efficacy of Small Interference RNA-Based Therapy on Respiratory Syncytial Virus Infection in Mice

Objective To observe the distribution of small interference RNA(siRNA)7816 in mice and the efficacy of siRNA-based therapy on respiratory syncytial virus(RSV)infection. Methods The siRNA labeled with cy3 fluorophore were intranasally introduced into the lung tissue of the mice.The mice were killed at 12 hours after infection,and their lung,liver and intestines were removed for immediate frozen section.The distribution of fluorescein-labeled siRNA was then observed under the fluorescence microscope.Forty-eig...