本文以构建的含人生长激素(hGH)cDNA的重组真核表达质粒为外源靶基因,研究了直接注射质粒及脂质体与质粒复合物后hGH在小鼠体内表达的情况.用RT-PCR技术检测hGH转录产物,用免疫放射检测分析法(IRMA)检测hGH蛋白质表达水平.结果发现,注射质粒与脂质体复合物组的表达效率高于单纯质粒组,Lipofectamine的作用强于Lipofectin,表明应用脂质体及直接注射法是使外源靶基因在小鼠体内表达的简便、有效途径.

An eukaryotic expression plasmid Rc/CMV GHcDNA containing CMV late promoter and hGH cDNA was constructed and introduced into mouse skeletal muscle by means of direct injection with or without the cationic liposome (Lipofectin and Lipofectamine reagent) intramuscularly. The expression of the gene was detected through both RT-PCR and IRMA (Immunoradiometric assay) at the level of transcription and protein respectively. The gene expression can be detected even after 90 days of single plasmid injection. Compared with the mice injected with the plasmid itself, the expression levels of mice injected with the plasmid-cationic liposome complex seem to be higher, and the expression period longer. Furthermore, the effect of Lipofectamine seems to be even better than that of Lipofectin. The results indicate that direct intramuscular injection with recombinant expression plasmid or plasmid-cationic liposome complex is a simple, efficient and economical way for foreign gene transfer and expression in experimental mice in vivo.