Short-chain phospholipids enhance amphipathic peptide-mediated gene transfer.

Addition of short-chain phospholipids to the gramicidin S-DNA-dioleoyl phosphatidylethanolamine complex enhanced up to 6-fold beta-galactosidase expression in several cell-lines in vitro. Among the compounds tested, the most potent in enhancing transfection were the dicapryl- and the dicapryloyl phosphatidylcholine. In contrast, no significant enhancement of transfection was seen when short-chain phospholipids were mixed with cationic lipids. Short-chain phospholipid and gramicidin S may act simultaneously on the cell membrane to enhance gene transfer, yet resulting in no toxicity.