经周围静脉途径转移的外源基因在大鼠体内的表达

Adenovirus-mediated LacZ Gene Expression in Different Organs of Wistar Rats by Intravenous Gene Transfer in Vivo

目的 :探讨经周围静脉注射的外源基因在大鼠体内不同组织的表达。方法 :将重组LacZ腺病毒经尾静脉注射导入Wistar大鼠体内 ,以X gal染色法明确腺病毒载体介导的标识基因 (LacZ)在大鼠体内的表达部位和时间。结果 :β gal表达具有剂量依赖性 ,而且存在器官、组织和细胞 3种水平的表达差异。剂量较小时 ,肺、肾、肝、脾优先表达 ,而心肌在 1× 10 1 1 pfu·kg- 1 剂量组才有少量表达 ,大血管和脑组织始终未见表达。注射后 1～ 2周 ,大鼠的肾、肺、肝、脾、肾上腺高表达 β 半乳糖苷酶 ,3～ 4周表达量减少 ,5周基本消失。结论 :腺病毒介导的外源基因经静脉途径转移 ,可能是肾、肺。

Objective: To investigate the biodistribution and pharmacokinetics of adenovirus gene transfer vectors after intravenous injection in rats. Methods: Recombinant adenovirus vector containing LacZ called report gene (Ad/CMV.LacZ) was constructed by orientation clone and homologous recombination technology, and then was transferred to Wistar rats by injecting into tail veins. To identify the sites and periods of LacZ gene expression, X gal staining was usedto detect β gal level of different organs in the transfected and non transfected rats at different time intervals. Results: β gal expressed in a dose dependent manner after Ad/CMV. LacZ injection. Furthermore, there were marked difference of β gal expression among different organs, different tissues and different cells. Three days to four weeks after injection, the kidneys, lungs, livers, spleens and adrenal glands expressed β gal in a high level, and their peak level were in 1 to 2 weeks. Five weeks after injection, β gal expression disappeared in most organs except kidneys. The myocardium in left ventricles showed low level β gal expression only in high dose group(1×10 11 pfu·kg -1 ). In all animals, aorta, renal artery, cava and brain did not appear any β gal expression. Conclusion: The results indicate that adenovirus mediated exogenous gene can be expressed in most organs of rats for 4 weeks after single intravenous injection. It was suggested intravenous gene transfer would be an effective approach of treating some diseases involved kidneys, livers and lungs.