Innovative nanotechnologies for enhancing nucleic acids/gene therapy: Controlling intracellular trafficking to targeted biodistribution

Abstract

Nanomedicine promises to play an important role in next generation therapy, including Nucleic acid/Gene therapy. To accomplish this, innovative nanotechnologies will be needed to support nanomedicine by controlling not only the biodistribution but also the intracellular trafficking of macromolecules such as RNA/DNA. A multifunctional envelope-type nano device (MEND) was developed to meet this requirement. We herein provide an update regarding the functions of the MEND system focusing on the introduction of different functional biomaterials that enhance efficiency. The octaarginine (R8) peptide enhances cellular uptake and controls intracellular trafficking to induce synergism in transgene expression. The R8 was also used for developing a MITO-Porter system for mitochondrial targeting. The function of the MITO-Porter system was extended by developing a mitochondrial reporter gene for mitochondrial gene therapy. For efficient in vivo gene delivery, new pH-sensitive lipids have been introduced to achieve controlled biodistribution and to enhance endosomal escape. For example, the CL4H6 lipid exerts a more efficient in vivo gene silencing than that of ONPATTRO^TM, a preparation that has been approved by the US Food and Drug Administration. We further summarize new technologies that have been successfully applied to cancer immunotherapy leading to the introduction of a new strategy based on the concept of the Cancer-Immunity Cycle.

Keywords: MEND; MITO-Porter; YSK; adjuvant; cancer immunotherapy; pH-sensitive cationic lipid.