Ilies Marc A, Johnson Betty H, Makori Fred, Miller Aaron, Seitz William A, Thompson E Brad, Balaban Alexandru T
Department of Marine Sciences, Texas A and M University at Galveston, 5007 Avenue U, Galveston, TX 77551, USA.
Arch Biochem Biophys. 2005 Mar 1;435(1):217-26. doi: 10.1016/j.abb.2004.12.010.
Cationic lipids provide a promising alternative to the use of viruses for delivering genes therapeutically. Among the several classes of lipidic vectors, those bearing a heterocyclic cationic head have shown important advantages, such as low cytotoxicity and improved efficiency across different cell lines. We recently reported a simple and efficient strategy for obtaining pyridinium cationic lipids, starting from pyrylium salts and primary amines. The present study is aimed to compare the cellular toxicity and transfection efficiency generated by the pyridinium polar head versus the tetramethylammonium one on several tumor cell lines and also in experimental animals, delivered via intratumor injections. Thus, the lead compound 1-(2,3-dioleoyloxypropyl)-2,4,6-trimethylpyridinium lipid (2Oc), coformulated with different helper lipids in various molar ratios, was tested against its ammonium congener DOTAP-a standard transfection reagent. The results revealed that when formulated with cholesterol at 1:1 molar ratio, the pyridinium lipid 2Oc was able to transfect several cancer cell lines with similar or better efficiency than its tetraalkylammonium congener DOTAP, while producing lower cytotoxicity. The NCI-H23 lung cancer cell line was found to be the most susceptible to be transfected. Therefore, we designed an in vivo assay based on this type of carcinoma in nude mice, which were injected intratumoral with 2Oc- and DOTAP-based lipoplexes. The red fluorescent protein reporter revealed that the pyridinium cationic lipid was superior to its tetraalkylammonium congener, transfecting the tissue on a higher area and with higher efficiency. These encouraging findings, together with the simple and efficient synthetic strategy, lay the foundation for further development of pyridinium lipids for gene therapy with improved transfection efficiency in vivo and even further reduced cytotoxicity.
阳离子脂质为治疗性基因递送提供了一种有前景的替代病毒的方法。在几类脂质载体中，带有杂环阳离子头部的脂质已显示出重要优势，如低细胞毒性和在不同细胞系中提高的效率。我们最近报道了一种从吡喃鎓盐和伯胺出发获得吡啶鎓阳离子脂质的简单高效策略。本研究旨在比较吡啶鎓极性头部与四甲基铵头部在几种肿瘤细胞系以及实验动物中通过瘤内注射递送时产生的细胞毒性和转染效率。因此，将先导化合物1-(2,3-二油酰氧基丙基)-2,4,6-三甲基吡啶鎓脂质(2Oc)与不同辅助脂质以各种摩尔比共配制，针对其铵同类物DOTAP（一种标准转染试剂）进行测试。结果显示，当与胆固醇以1:1摩尔比配制时，吡啶鎓脂质2Oc能够以与其四烷基铵同类物DOTAP相似或更高的效率转染几种癌细胞系，同时产生更低的细胞毒性。发现NCI-H23肺癌细胞系最易被转染。因此，我们基于这种类型的癌在裸鼠中设计了一种体内试验，向其瘤内注射基于2Oc和DOTAP的脂质体复合物。红色荧光蛋白报告基因显示，吡啶鎓阳离子脂质优于其四烷基铵同类物，在更大面积且以更高效率转染组织。这些令人鼓舞的发现，连同简单高效的合成策略，为进一步开发吡啶鎓脂质用于基因治疗奠定了基础，有望在体内提高转染效率并进一步降低细胞毒性。
