Research Article

In Vitro Gene Delivery Mediated by Asialofetuin-Appended Cationic Liposomes Associated with γ-Cyclodextrin into Hepatocytes

Table 4

Encapsulation ratio of pDNA into AF-liposomes and gene transfer activity of pDNA/AF-liposomes at various cycles of freeze-thaw in HepG2 cells.

Freeze thaw cycleEncapsulation ratio of pDNA (%)Gene transfer activity (fold)

035.2 0.90.56 0.07
136.2 0.50.59 0.06
237.4 2.10.76 0.02
342.4 4.31
544.1 1.31.03 0.02

The charge ratio of AF-liposomes/pDNA was 1.6. pDNA/AF-liposome was prepared using a freeze-thaw method which was repeated from 0 to 5 cycles. Cells were incubated with pDNA/γ-CyDs/AF-liposome for 3 h in FCS-free medium. After washing twice, the cells were incubated for 21 h in culture medium supplemented with 10% FCS. The luciferase activity in cell lysates was determined using a luminometer. Each value represents the mean SEM of 3 experiments.