動態-発現相関の解析に基づくin vivo遺伝子導入キャリアーシステムの分子設計

体内基因治疗作为治疗多种疾病的先进方法之一，越来越受到人们的关注。为了成功地进行基因治疗，必须开发出选择性、有效地将基因传递到靶点的载体。本研究分析了质粒DNA与大分子和微粒载体复合后的药代动力学与基因表达的关系，并提出了利用带有特异性配体的大分子和微粒载体控制基因传递的策略。体外基因转染实验发现糖基化阳离子大分子和脂质体通过糖识别机制有效地进行特异性递送。并对质粒DNA复合物的药代动力学和体内基因转染进行了研究。当质粒DNA复合糖基化载体门静脉内注射，它选择性地积累，并表现出在肝脏中的转染活性。膜融合肽被引入到糖基化的阳离子聚（氨基酸），以控制质粒DNA复合物的细胞内运输。该复合物是非常有效的和肝脏特异性，即使静脉注射。在整个研究过程中，我们证明了外源基因的体内表达通过控制其药代动力学得到了很大的改善，并开发了针对各种疾病如肝脏疾病的基因递送系统的原型。

In vivo gene therapy is increasingly attractive as one of advanced therapeutic methodologies against various diseases. For successful gene therapy, it is necessary to develop the carriers delivering gene to the target in a selective and effective manner. In this study, we analyzed relationship between pharmacokinetics and gene expression of plasmid DNA complexed with macromolecular and particulate carriers, and developed some strategies for controlling gene delivery using macromolecular and particulate carriers bearing specific ligands. In vitro gene transfection experiments found glycosylated cationic macromolecules and liposomes effective for specific delivery via sugar recognition mechanisms. The pharmacokinetics and in vivo gene transfection of plasmid DNA complexes were also investigated. When plasmid DNA complexed with glycosylated carriers was intraportally injected, it selectively accumulated and exhibited transfection activity in the liver. Membrane-fusogenic peptides were introduced to glycosylated cationic poly (amino acids), to control an intracellular trafficking of plasmid DNA complexes. The complexes were highly effective and liver-specific even when intravenously injected. Throughout this study, we demonstrated that in vivo expression of exogenous genes was much improved by controlling their pharmacokinetics, and developed the prototypes of gene delivery systems towards various diseases such as hepatic disorders.