Inoh Yoshikazu, Kitamoto Dai, Hirashima Naohide, Nakanishi Mamoru
Graduate School of Pharmaceutical Sciences, Nagoya City University, Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan.
J Control Release. 2004 Feb 10;94(2-3):423-31. doi: 10.1016/j.jconrel.2003.10.020.
Biosurfactants, which are surface-active compounds produced by microorganisms growing on water-insoluble substrates, have many biological activities. We studied here three different biosurfactants, mannosylerythritol lipid (MEL) or 4-O-[(4',6'-di-O-acetyl-2',3'-di-O-alkanoyl)-beta-D-mannopyranosyl] meso-erythritol (MEL-A), 4-O-[(6'-O-acetyl-2',3'-di-O-alkanoyl)-beta-D-mannopyranosyl] meso-erythritol (MEL-B) and 4-O-[(4'-O-acetyl-2',3'-di-O-alkanoyl)-beta-D-mannopyranosyl] meso-erythritol (MEL-C). MEL-A enhanced the efficiency of gene transfection by cationic liposomes, but MEL-B and MEL-C did not. We also studied the localization of FITC-conjugated antisense DNAs (15-mer oligonucleotides; phosphorothioate) in the target cells by confocal laser scanning microscopy (CLSM). The FITC-conjugated antisense oligonucleotides were temporarily on the plasma membrane of the target cells, thereafter they were transferred into the nucleus of the target cells. In the case of MEL-B and MEL-C, such localization of DNA was not observed both in the plasma membrane and in the nucleus. The results obtained by CLSM images were in good agreement with the transfection efficiency. This suggests that MEL-A induces the membrane fusion between the target cells and the cationic liposomes, accelerating the efficiency of gene transfection dramatically.
生物表面活性剂是微生物在水不溶性底物上生长产生的表面活性化合物，具有多种生物活性。我们在此研究了三种不同的生物表面活性剂，甘露糖赤藓糖醇脂（MEL）或4-O-[(4',6'-二-O-乙酰基-2',3'-二-O-链烷酰基)-β-D-甘露吡喃糖基]内消旋赤藓糖醇（MEL-A）、4-O-[(6'-O-乙酰基-2',3'-二-O-链烷酰基)-β-D-甘露吡喃糖基]内消旋赤藓糖醇（MEL-B）和4-O-[(4'-O-乙酰基-2',3'-二-O-链烷酰基)-β-D-甘露吡喃糖基]内消旋赤藓糖醇（MEL-C）。MEL-A提高了阳离子脂质体的基因转染效率，但MEL-B和MEL-C没有。我们还通过共聚焦激光扫描显微镜（CLSM）研究了异硫氰酸荧光素（FITC）偶联的反义DNA（15聚体寡核苷酸；硫代磷酸酯）在靶细胞中的定位。FITC偶联的反义寡核苷酸暂时位于靶细胞的质膜上，随后转移到靶细胞的细胞核中。在MEL-B和MEL-C的情况下，在质膜和细胞核中均未观察到DNA的这种定位。CLSM图像获得的结果与转染效率高度一致。这表明MEL-A诱导靶细胞与阳离子脂质体之间的膜融合，显著提高基因转染效率。
