Receptor-mediated transfer of pSV2CAT DNA to mouse liver cells using asialofetuin-labeled liposomes.
Receptor-mediated transfer of pSV2CAT DNA to mouse liver cells using asialofetuin-labeled liposomes.
复制标题
使用脱唾液酸胎球蛋白标记的脂质体，通过受体介导将 pSV2CAT DNA 转移至小鼠肝细胞。
作者：
T. Hara;Y. Aramaki;S. Takada;K. Koike;S. Tsuchiya
无唾液酸胎球蛋白标记的脂质体（AF-脂质体）被开发为具有高转染活性的非病毒载体，用于通过全身给药将受体介导的基因转移至肝细胞。最初，大多数pSV 2CAT，氯霉素乙酰转移酶（CAT）基因表达质粒，与AF-脂质体（AF-脂质体-pSV 2CAT），并将它们注射到成年小鼠的门静脉。在肝脏中观察到显著高的CAT活性。通过使用完全包封pSV 2CAT的AF-脂质体，肝脏中的CAT活性进一步增加两倍。另一方面，未标记的对照脂质体在肝脏中的CAT活性低于脾或肺。CAT mRNA水平反映了各组织中各脂质体制剂获得的CAT活性。免疫组织化学染色显示CAT在门静脉周围大量的实质细胞中产生。包封在脂质体的内部水层中的质粒被有效地保护免于环境降解。因此，通过施用到血液循环中，AF-脂质体将通过受体介导的内吞作用成功地掺入肝细胞中，并且包封的质粒将转移到细胞内途径。
Asialofetuin-labeled liposomes (AF-liposomes) were developed as a nonviral vector having high transfection activity for receptor-mediated gene transfer to hepatocytes by systemic administration. Initially, the majority of pSV2CAT, a chloramphenicol acetyltransferase (CAT) gene expression plasmid, was associated with AF-liposomes (AF-liposome-pSV2CAT), and they were injected into the portal vein of an adult mouse. Significantly high CAT activity was observed in the liver. The CAT activity in the liver was further increased two-fold by using AF-liposomes completely encapsulating pSV2CAT. Nonlabeled control liposomes, on the other hand, showed lower CAT activity in the liver than in the spleen or lung. The level of CAT mRNA reflected the CAT activity obtained by each liposome preparation in each tissue. Immunohistochemical staining showed that CAT was produced in a large number of parenchymal cells localizing in the periportal area. The plasmid encapsulated in the internal aqueous layer of the liposomes was effectively protected from environmental degradation. Thus, by administration into the blood circulation, AF-liposomes would be successfully incorporated into hepatocytes through receptor-mediated endocytosis, and the encapsulated plasmid would be transferred to the intracellular pathway.