Exosome-mediated delivery of Cas9 ribonucleoprotein complexes for tissue-specific gene therapy of liver diseases

CRISPR-Cas9 gene editing has emerged as a powerful therapeutic technology, but the lack of safe and efficient in vivo delivery systems, especially for tissue-specific vectors, limits its broad clinical applications. Delivery of Cas9 ribonucleoprotein (RNP) owns competitive advantages over other options; however, the large size of RNPs exceeds the loading capacity of currently available delivery vectors. Here, we report a previously unidentified genome editing delivery system, named exosomeRNP, in which Cas9 RNPs were loaded into purified exosomes isolated from hepatic stellate cells through electroporation. ExosomeRNP facilitated effective cytosolic delivery of RNP in vitro while specifically accumulated in the liver tissue in vivo. ExosomeRNP showed vigorous therapeutic potential in acute liver injury, chronic liver fibrosis, and hepatocellular carcinoma mouse models via targeting p53 up-regulated modulator of apoptosis (PUMA), cyclin E1 (CcnE1), and K (lysine) acetyltransferase 5 (KAT5), respectively. The developed exosomeRNP provides a feasible platform for precise and tissue-specific gene therapies of liver diseases.

Automated summary

CRISPR-Cas9 gene editing is a powerful therapeutic technology, but the lack of safe and efficient in vivo delivery systems limits its clinical applications. Researchers have developed a novel gene editing delivery system, called exosomeRNP, which loads Cas9 RNPs into purified exosomes derived from hepatic stellate cells. exosomeRNP enables effective cytosolic delivery of RNPs in vitro and specifically accumulates in liver tissue in vivo. By targeting different genes, exosomeRNP demonstrates considerable therapeutic potential in acute liver injury, chronic liver fibrosis, and hepatocellular carcinoma mouse models. This study provides a feasible platform for precise and tissue-specific gene therapies for liver diseases.