Multifunctional envelope-type nano device for controlled intracellular trafficking and selective targeting in vivo

Nanomedicine is expected to be a basic technology for using nucleic acids as a drug, in which treating the cause of diseases represent the ultimate therapy. However, a sophisticated delivery system is required for efficient delivery of RNA/DNA, since these compounds need precise control of intracellular trafficking as well as biodistribution. Here we report on the use of a multifunctional envelope-type nano device (MEND) which is capable of intracellular trafficking such as endosomal escape, delivery to mitochondria, as well as active targeting to selective tissues/cells in vivo. In this review, we focused on the controlled intracellular trafficking of antigens for advanced immunotherapy, and then introduced a mitochondrial delivery system as an organelle targeting system for unmet medical needs. We also provide a successful in vivo delivery of siRNA to the liver based on a newly designed pH-responsive cationic lipid. Finally we will discuss an important role of an active targeting system using a peptide ligand to adipose vasculature. These progresses in drug delivery system will break through the barriers exist in our body, tissues and cells and open a window for future Nanomedicine.