Yang J P, Huang L
Department of Pharmacology, University of Pittsburgh School of Medicine, PA 15261, USA.
Gene Ther. 1998 Mar;5(3):380-7. doi: 10.1038/sj.gt.3300596.
Following our previous finding that increasing charge ratio (+/-) can overcome the serum sensitivity of cationic liposome-DNA complex, in the present studies we report that serum sensitivity of cationic liposome-DNA complex could also be overcome by prolonging the incubation time of the complex. Such time-dependent maturation of the complex was cationic lipid-dependent; complexes containing monovalent cationic lipids, eg DC-chol, DOTAP and lipofectin, matured with time, but those containing multivalent lipid, eg lipofectamine, do not. High charge ratio high concentration and high temperature accelerated the process of maturation. The serum sensitivity of cellular uptake of DNA was also dependent on the incubation time. The matured cationic liposome-DNA complexes are homogeneous particles with a mean diameter of 170 to 400 nm, depending on the cationic lipid in the complex.
根据我们之前的发现，即增加电荷比（+/-）可以克服阳离子脂质体 - DNA复合物的血清敏感性，在本研究中我们报告，延长复合物的孵育时间也可以克服阳离子脂质体 - DNA复合物的血清敏感性。这种复合物的时间依赖性成熟是阳离子脂质依赖性的；含有单价阳离子脂质（如DC - 胆固醇、DOTAP和脂质体转染试剂）的复合物会随时间成熟，但含有多价脂质（如脂质体2000）的复合物则不会。高电荷比、高浓度和高温加速了成熟过程。DNA细胞摄取的血清敏感性也取决于孵育时间。成熟的阳离子脂质体 - DNA复合物是平均直径为170至400nm的均匀颗粒，这取决于复合物中的阳离子脂质。
