Igarashi Saki, Hattori Yoshiyuki, Maitani Yoshie
Institute of Medicinal Chemistry, Hoshi University, Ebara 2-4-41, Tokyo 142-8501, Japan.
J Control Release. 2006 May 30;112(3):362-8. doi: 10.1016/j.jconrel.2006.03.003. Epub 2006 Apr 19.
Mannnosylerythritol lipid A (MEL-A), a biosurfactant produced by microorganisms, has many biological activities. To enhance the gene transfection efficiency of a cationic liposome, we prepared a MEL-liposome (MEL-L) composed of 3beta-[N-(N',N'-dimethylaminoethane)-carbamoyl] cholesterol (DC-Chol), dioleoyl phosphatidylethanolamine (DOPE) and MEL-A, and investigated its transfection efficiency in human cervix carcinoma Hela cells. MEL-L was about 40 nm in size, and the MEL-L/plasmid DNA complex (MEL-lipoplex) remained an injectable size (169 nm). MEL-A induced a significantly higher level of gene expression, compared to commercially available Tfx20 and the liposome without MEL-A (Cont-L). Analysis of flow cytometric profiles clearly indicated that the amount of DNA associated with the cells was rapidly increased and sustained by addition of MEL-A to the liposome. Confocal microscopic observation indicated that the MEL-lipoplex distributed widely in the cytoplasm, and the DNA was detected strongly in the cytoplasm and around the nucleus, compared with Cont-L. These results suggested that MEL-A increased gene expression by enhancing the association of the lipoplexes with the cells in serum. MEL-L might prove a remarkable non-viral vector for gene transfection and gene therapy.
甘露糖赤藓糖醇脂A（MEL-A）是一种由微生物产生的生物表面活性剂，具有多种生物活性。为提高阳离子脂质体的基因转染效率，我们制备了一种由3β-[N-（N'，N'-二甲基氨基乙烷）-氨基甲酰基]胆固醇（DC-Chol）、二油酰磷脂酰乙醇胺（DOPE）和MEL-A组成的MEL脂质体（MEL-L），并研究了其在人宫颈癌Hela细胞中的转染效率。MEL-L的大小约为40nm，MEL-L/质粒DNA复合物（MEL-脂质复合物）的大小仍适合注射（169nm）。与市售的Tfx20和不含MEL-A的脂质体（对照-L）相比，MEL-A诱导的基因表达水平显著更高。流式细胞仪分析结果清楚地表明，向脂质体中添加MEL-A可使与细胞结合的DNA量迅速增加并持续保持。共聚焦显微镜观察表明，与对照-L相比，MEL-脂质复合物在细胞质中广泛分布，并且在细胞质和细胞核周围均能强烈检测到DNA。这些结果表明，MEL-A通过增强脂质复合物与血清中细胞的结合来增加基因表达。MEL-L可能是一种用于基因转染和基因治疗的出色非病毒载体。
