Abstract 106: Novel Nanoparticle-mediated Robust Genome Editing Targeting The Vascular Endothelium Of Postnatal And Adult Mice

Current viral and non-viral delivery of transgene after i.v. administration is mainly enriched in the liver. To target the vascular endothelium for robust genome editing in adults, we developed a a novel nanoparticle system. A single i.v. administration of the mixture of nanoparticles and all-in-one plasmid DNA expressing Cas9 controlled by CDH5 promoter and guide RNA by U6 promoter induced highly efficient genome editing in endothelial cells of the vasculatures including lung, heart, aorta, and the peripheral vessels in adult mice in as quick as 5 days. Western blotting and immunofluorescent staining demonstrated an 80% decrease of protein expression selectively in endothelial cells, resulting in a phenotype similar to that of genetic knockout mice. This nanoparticle /plasmid delivery system could also deliver a transgene targeting the vascular endothelium simultaneously and/or multiple gRNAs to knockout multiple genes at the same time. The nanoparticle/plasmid DNA delivery system could also achieve robust gene-correction through a base editor in the vascular endothelium in adult mice. These data demonstrate that nanoparticle delivery of plasmid DNA expressing a genome editing system (e.g., CRISPR/Cas9, or base editor, etc.) and/or a transgene is a simple powerful tool to rapidly and efficiently alter expression of gene(s) in vascular endothelium. This provides a significant advance in cardiovascular research and a potential novel gene therapy strategy for cardiovascular diseases.