Development of organ specific transfection methods by using liposomes.

我们比较了由各种脂质组成的带正电荷的脂质体的转染效率。在所用的阳离子脂质体中，由TMAG、DOPE和DLPC组成的脂质体显示出高得多的质粒DNA包封效率，并且在无血清或有血清存在下均给出高效转染。阳离子脂质体的转染效率受脂质体组成、脂质体类型和血清存在的影响，我们研究了阳离子脂质体是否能有效地将绵羊白血病病毒（BLV）长末端重复序列控制的白喉毒素A链（DT-A）基因导入BLV感染的细胞中，并适用于体内应用。该脂质体可作为BLV感染细胞的有效转染试剂，并可用于DT-A基因的体内转染，将脂质体注射到大鼠角膜、虹膜、睫状体和视网膜中，可实现DT-A基因的高效稳定转染。我们发现，滴眼液中的表达质粒载体携带的特定类型的脂质体可以将基因转移到大鼠视网膜神经节细胞，而不引起任何炎症。本研究采用脂质体转染法，观察了以原癌基因和细胞周期相关核蛋白为靶点的反义寡核苷酸对系膜细胞增殖的影响。反义寡核苷酸抑制系膜细胞增殖。反义TGF-β和PDGF-B链抑制Thy 1肾小球肾炎模型中细胞外基质积聚和系膜细胞增殖。这些结果表明，反义寡核苷酸作为一类新的治疗药物在肾小球疾病的治疗的可行性。

We compared the transfection efficiency of the positively charged liposomes composed of various lipids. In the cationic liposomes used, the liposomes composed of TMAG,DOPE,and DLPC showed an much higher efficiency for the plasmid DNA entrapment, and gave highly efficient transfection in the absence or presence of serum. The transfection efficiency of the cationic liposomes is affected by the lipid composition, type of liposomes, or the presence of serum.We investigated whether cationic liposomes are efficient at delivering the gene fo diphtheria toxin A-chain (DT-A) under the control of the long terminal repeats of lovine leukemia virus (BLV) in to BLV-infected cells and are also sutable for in vivo use. The cationic liposomes may be efficient transfection reagent for the BLV-infected cells and can be utilized for DT-A gene delivery into BLF-infected cells in vivo.Efficient and stable transfer of the functional gene could be achived by injection of liposomes in the cornea, iris, ciliary body, and retina of rats. We showed that instillation as eye drops of an expression plasmid vector carried by the specific kinds of liposomes could transfer the gene to the reinal ganglion cells of rat, without causing any inflammation. This non-surgical, convenient way for gene delivery to the reina would facilitate the development of treatment for vsrious inraocular desease.Anti-proliferative effect of antisense oliponucleotides targeting the proto-oncogenes and cell-cycle associated nuclear proteins on mesangial cells by tranfection of liposome methods were examined. The antisense oligonucleotides suppressed the mesagial cell proliferation. Antisense TGF-beta and PDGF-B chain inhibited accumulation of extracellular matrix and mesangial cell proliferation in Thy 1 glomelonephritis model. These results indicate the feasibility of antisense oligonucleotide as a novel class of therapeutic agents in the treatment of glomerular diseases.