Abstract B56: Breaching endosomal barriers for carried-mediated intracellular delivery of messenger RNA

Abstract

Abstract RNA therapeutics represents a new class of modern medicine for targets considered undruggable. Lipid based nanoparticles (LNPs) based platforms remain the most advanced in clinical trials for RNA based drugs. Yet, the lack of mechanistic insights into the cellular trafficking and endosomal escape of nanoparticles has become a major hurdle for efficient intracellular delivery. We have 1) Dissected the productive sites for endosomal escape by utilizing an CRISPR/Cas9 based genetically altered cells targeted against endosomal proteins, that direct nanoparticles towards the early, recycling, late or lysosomal delivery. The disruption of key steps in endocytic trafficking revealed the active sites for endosomal escape 2) Identified novel compounds that improve escape from productive endocytic compartments. These molecules were selected based on their properties of influencing endo/lysosomal system that can trigger endosomal escape. Our investigation reveals that endo/lysosomal transport drives intracellular delivery of LNP delivered mRNA and we were able to pinpoint key stages of endosomal escape using genetically altered cells. Novel compounds that can improve cytosolic delivery of mRNA have been identified and are being further interrogated for their ability to breach endosomal barriers. Our goal is to unlock the mechanisms of carrier-mediated intracellular delivery, unravel productive sites of endosomal escape and identify compounds that enable intracellular mRNA delivery for the treatment of various devastating disorders including cancer. Citation Format: Siddhrath Patel, Gaurav Sahay. Breaching endosomal barriers for carried-mediated intracellular delivery of messenger RNA. [abstract]. In: Proceedings of the AACR Special Conference on Engineering and Physical Sciences in Oncology; 2016 Jun 25-28; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2017;77(2 Suppl):Abstract nr B56.