New strategies for nucleic acid delivery to conquer cellular and nuclear membranes.

After administration to the body, nucleic acid containing nanoparticles (NANs) need to cross several extra- and intracellular barriers to reach the cytoplasm or nucleus of the target cells. In the last decade several groups tried to overcome these barriers by arming non-viral delivery systems with targeting moieties, polyethylene glycol chains, fusogenic peptides and so forth. However, the drawback of this upgrading strategy is that each of the encountered barriers requires a new functionality, leading to very complex multi-component NANs. Moreover, there are currently no components available that can efficiently transport genes or NANs inside the nucleus of non-dividing cells. In this article a new, ultrasound based delivery system that possesses the capacity to simultaneously overcome several key barriers in non-viral nucleic acid delivery is presented. Additionally, a small amphiphilic compound that induces nuclear uptake of plasmid DNA and enhances non-viral gene transfer is presented.