3Beta [N-(N',N'-dimethylaminoethane)-carbamoyl] cholesterol (DC-Chol)-mediated gene delivery to primary rat neurons: characterization and mechanism.

Cationic lipid formulations consisting of 3beta [N-(N', N'-dimethylaminoethane)-carbamoyl] cholesterol (DC-Chol) and the helper lipid dioleoylphosphatidylethanolamine (DOPE) (1.5: 1 molar ratio) were prepared by solvent evaporation and sized by high pressure extrusion. Liposomes made of 1:1 molar ratio 1 ,2-dioleoyl-3-trimethyl-ammonium-propane (DOTAP)/DOPE were used as controls in the study. The two formulations were characterized and evaluated for their efficiency in transfecting SKnSH (neuroblastoma) and primary rat neuronal cell lines. DC-Chol/DOPE liposomes were more efficient at transfecting both the SKnSH and the primary rat neuronal cells and also less toxic compared to the DOTAP/DOPE liposomes. The cellular-associated signal of rhodamine-labeled DC-Chol/DOPE liposomes into SKnSH and primary rat neuronal cells was higher than the rhodamine-labeled DOTAP/DOPE liposomes. These results demonstrate that DC-Chol/DOPE cationic liposomes provide an efficient vehicle for the delivery of plasmids into SKnSH and primary neuronal cells compared to DOTAP/DOPE liposomes. DC-Chol/DOPE liposomes may provide a good non-viral candidate for transfecting primary rat neuronal cells.