Effective prevention of atherosclerosis by non-viral delivery of CRISPR/Cas9

Atherosclerosis (AS) is one of the most critical reasons behind the high morbidity and mortality of cardiovascular diseases. Limited therapeutic options are available to effectively preventing AS. Recently, clustered, regularly interspaced, short palindromic repeat/CRISPR-associated nuclease 9 (CRISPR/Cas9)-based genome-editing technology has shown great potential to permanently silence Pcsk9 gene to decrease cholesterol level and prevent AS. However, due to the poor ability of gene editing and the arising gene off-target, delivering the CRISPR/Cas9 system effectively to the liver for in vivo gene editing of AS is still a challenge. Herein, we reported a non-viral CRISPR/Cas9 delivery nanosystem (PuPGEA/pCas9-Pcsk9) composed of low-toxic and liver-targeting polycation (pullulan-based ethanolamine-modified poly(glycidyl methacrylate), PuPGEA), which can efficiently deliver a plasmid pCas9-Pcsk9 for the knockout of Pcsk9 gene. PuPGEA/pCas9-Pcsk9 nanosystem can effectively knock out Pcsk9 in embryonic liver cells of mice (BNL CL.2) in vitro. Particularly, compared with the control group (linear polycationic without polysaccharide), PuPGEA/pCas9-Pcsk9 nanosystems can effectively target liver and successfully edit Pcsk9, which contributed to the effective decrease of cholesterol level. Such a targeted therapeutic modality with CRISPR/Cas9 system exhibits impressive performances in preventing the process of AS, providing a programmed strategy for the design of CRISPR/Cas9 treatment system for various genetic liver diseases and vascular diseases.