Immersion delivery of plasmid DNA. I. A study of the potentials of a liposomal delivery system in XXXX ( @entity5660 ) fry.

@entity5660 @entity137 @entity519
A successful regime for intramuscular injection of naked DNA is developed in fish, but the exploration of other ways of administration has not yet been studied in any detail. Immersion is a delivery route offering many advantages compared to conventional ways of administration. Applying cationic liposomes as a delivery system for DNA by this route, however, is met with severe @entity137 problems. In this report, the underlying mechanisms of the acute @entity137 were investigated in vivo and in vitro. The most critical factor was found to be the charge of the liposomes. Cationic liposomes above a certain threshold concentration had a lethal effect in @entity5660 fry. In contrast, similar concentrations of neutral or anionic liposomes were not toxic. Furthermore, large liposome-mucin complexes were formed upon addition of mucin to cationic liposomes. This was not observed with neutral or anionic liposomes. Lipoplexes were less toxic and interacted less with mucin compared to cationic liposomes. Hence, the mechanism of the acute @entity137 in @entity5660 fry is suggested to be an interaction between the cationic liposomes and anionic components of gill mucin. The consequence is @entity519 and this is most likely the cause of acute @entity137 observed in @entity5660 fry.
