Progress in the development of ultrasound-mediated gene delivery systems utilizing nano- and microbubbles

Recently, ultrasound-mediated gene delivery with nano- and microbubbles was developed as a novel non-viral vector system. In this gene delivery system, microstreams and microjets, which are induced by disruption of nano/microbubbles exposed to ultrasound, are used as the driving force to transfer genes into cells by opening transient pores in the cell membrane. This system can directly deliver plasmid DNA and siRNA into cytosol without endocytosis pathway. Therefore, these genes are able to escape from degradation in lysosome and result in enhancing the efficiency of gene expression. In addition, it is expected that ultrasound-mediated gene delivery using nano/microbubbles would be a system to establish non-invasive and tissue specific gene expression because ultrasound can transdermally expose to target tissues and organs. This review focuses on the current ultrasound-mediated gene delivery system using nano/microbubbles. We discuss about the feasibility of this gene delivery system as novel non-viral vector system.