Sandig V, Löser P, Lieber A, Kay M A, Strauss M
Max-Planck-Gesellschaft, Humboldt-Universität, Max-Delbrück Center for Molecular Medicine, Berlin, Germany.
Gene Ther. 1996 Nov;3(11):1002-9.
In vivo approaches to liver gene therapy will require restriction of transgene expression to hepatocytes. Since targeting of viral vectors exclusively to the liver is not easy to achieve, use of liver-specific promoters for driving expression of therapeutic genes is an interesting alternative. We have shown previously that regulatory elements of the hepatotrophic hepatitis B virus (HBV) are strong and liver-specific in vitro and therefore might be useful in hepatic gene therapy. Here we describe recombinant adenoviruses in which the human LDL receptor gene is under the transcriptional control of the HBV core promoter, the core promoter linked directly to HBV enhancer I, or a HBV-CMV hybrid promoter, respectively. These viruses allowed for a moderate to strong expression of the LDL receptor gene in vitro in a hepatocyte-specific manner when compared with the CMV immediate-early promoter. In vivo experiments demonstrated that the promoter gave rise to an expression level comparable to that from the CMV promoter in mouse liver, but was very weak in lung and skeletal muscle. Thus, the HBV-CMV hybrid promoter is strong and hepatocyte specific both in vitro and in vivo even in the adenoviral context and would be a good choice for driving a therapeutic gene in liver gene therapy.
肝脏基因治疗的体内方法需要将转基因表达限制在肝细胞中。由于将病毒载体专门靶向肝脏并不容易实现，因此使用肝脏特异性启动子来驱动治疗性基因的表达是一种有趣的替代方法。我们之前已经表明，嗜肝性乙型肝炎病毒（HBV）的调控元件在体外具有很强的肝脏特异性，因此可能在肝脏基因治疗中有用。在此，我们描述了重组腺病毒，其中人低密度脂蛋白受体基因分别受HBV核心启动子、直接与HBV增强子I相连的核心启动子或HBV-CMV杂交启动子的转录控制。与CMV立即早期启动子相比，这些病毒在体外以肝细胞特异性方式允许低密度脂蛋白受体基因适度至强表达。体内实验表明，该启动子在小鼠肝脏中的表达水平与CMV启动子相当，但在肺和骨骼肌中非常弱。因此，即使在腺病毒环境中，HBV-CMV杂交启动子在体外和体内均具有很强的肝脏特异性，将是肝脏基因治疗中驱动治疗性基因的良好选择。
