A novel Drug Delivery System Using HBV Envelop Protein Particles

有许多肝病可能是基因治疗的候选者。基因治疗需要一种载体，它与其基因一起被携带到靶细胞或器官中。理想的载体应该是极其安全的，具有良好的转染效率，并表现出高度的靶标特异性。1992年，黑田东彦等人提出。报道了在酵母细胞中可以合成大量的乙肝表面抗原包膜L颗粒。酵母菌产生的乙肝病毒包膜L颗粒是中空的纳米颗粒(平均直径80 nm)，显示了人类肝脏特异性感染所必需的前S1肽。通过电穿孔将绿色荧光蛋白(GFP)表达载体或荧光染料(钙黄绿素)导入L颗粒，并直接用于体外多种细胞的转染。绿色荧光蛋白或钙黄绿素衍生的荧光只在人类肝脏来源的细胞中观察到，如NUE和HepG2，而不是WiDR和A431。我们将人肝癌细胞和人结肠癌细胞移植到裸鼠或裸鼠的皮下。L颗粒与。通过尾静脉将GFP表达的胞外酰胺或Carcein感染到荷瘤裸鼠体内。7d后，大鼠皮下肝细胞癌、脑、心、肺、肝、脾、肾、肾上腺、肠、肌肉等皮下组织未见荧光。用L颗粒将血友病B的治疗基因人凝血因子IX基因转入异种移植模型后，血浆中的治疗因子IX水平至少维持1个月。综上所述，乙肝表面抗原L颗粒对人源性肝组织具有特异性识别能力，并在体内系统中表现出转基因能力。

There are many hepatopathies that may be candidates for gene therapy. Gene therapy needs a vector that is carried together with its genes into a target cell or organ. Desirable vectors should be extremely safe, have good transfection efficiency, and demonstrate a high specificity for their target. In 1992, Kuroda et al. reported on the large amount of HBsAg envelope L particles that could be synthesized in yeast cells. HBV envelope L particles overproduced by yeast are hollow nanoparticles(average diameter 80nm) displaying the pre-S1 peptide indispensable for human liver-specific infection. Either a GFP(green fluorescence protein)-expression plasmid or a fluorescent dye(calcein) was incorporated into L particles by electroporation, and directly used for the transfection of various cells in vitro. Either GFP- or calcein-derived fluorescence was observed only in human liver-derived cells such as NuE and HepG2 not but WiDr and A431. We transplanted human hepatocellular carcinoma cells and human colon cancer cells subcutaneously in nude rats or nude mice. L particles with. GFP-expression plasmide or carcein were infected into the tumor-bearing nude rats or mice through tail vein. After 7 days, fluorescence was observed specifically in the subcutaneous heptocellular carcinoma, but not was observed in the subcutaneous colon cancer, brain, heart, lung, liver, spleen, kidney, adrenal gland, intestine, or muscle of rats or mice. When the human clotting factor IX gene, a therapeutic gene for hemophilia B, was transferred into the xenograft model by the L particles, therapeutic factor IX levels were obtained in the plasma for at least 1 month. In conclusion, HBsAg L particles showed a specific recognition ability for human-derived liver tissue and demonstrated a transgenie ability in an in vivo system.