Macrophages are key effectors of host defense and metabolism, making them promising targets for transient genetic therapy. Gene editing through delivery of the Cas9-ribonucleoprotein (RNP) provides multiple advantages over gene delivery-based strategies for introducing CRISPR machinery to the cell. There are, however, significant physiological, cellular, and intracellular barriers to the effective delivery of the Cas9 protein and guide RNA (sgRNA) that have to date, restricted in vivo Cas9 protein-based approaches to local/topical delivery applications. Herein we describe a new nanoassembled platform featuring co-engineered nanoparticles and Cas9 protein that has been developed to provide efficient Cas9-sgRNA delivery and concomitant CRISPR editing through systemic tail-vein injection into mice, achieving >8% gene editing efficiency in macrophages of the liver and spleen.
