biostudies-literatureWang XNIDDK NIH HHSHoward Hughes Medical InstituteNHLBI NIH HHSNIGMS NIH HHS783-6https://www.ebi.ac.uk/biostudies/studies/S-EPMC4850082biostudies-literatureUnknown36(5)Although early proof-of-concept studies of somatic in vivo genome editing of the mouse ortholog of proprotein convertase subtilisin/kexin type 9 (Pcsk9) in mice have established its therapeutic potential for the prevention of cardiovascular disease, the unique nature of genome-editing technology-permanent alteration of genomic DNA sequences-mandates that it be tested in vivo against human genes in normal human cells with human genomes to give reliable preclinical insights into the efficacy (on-target mutagenesis) and safety (lack of off-target mutagenesis) of genome-editing therapy before it can be used in patients.We used a clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated (Cas) 9 genome-editing system to target the human PCSK9 gene in chimeric liver-humanized mice bearing human hepatocytes. We demonstrated high on-target mutagenesis (approaching 50%), greatly reduced blood levels of human PCSK9 protein, and minimal off-target mutagenesis.This work yields important information on the efficacy and safety of CRISPR-Cas9 therapy targeting the human PCSK9 gene in human hepatocytes in vivo, and it establishes humanized mice as a useful platform for the preclinical assessment of applications of somatic in vivo genome editing.Arteriosclerosis, thrombosis, and vascular biologyCRISPR-Cas9 Targeting of PCSK9 in Human Hepatocytes In Vivo-Brief Report.PMC4850082R01 GM104464R01 HL118744R01 DK099571Zhang YMusunuru KWang XRaghavan ADing QChen TQiao LfalseCRISPR-Cas9 Targeting of PCSK9 in Human Hepatocytes In Vivo-Brief Report.Although early proof-of-concept studies of somatic in vivo genome editing of the mouse ortholog of proprotein convertase subtilisin/kexin type 9 (Pcsk9) in mice have established its therapeutic potential for the prevention of cardiovascular disease, the unique nature of genome-editing technology-permanent alteration of genomic DNA sequences-mandates that it be tested in vivo against human genes in normal human cells with human genomes to give reliable preclinical insights into the efficacy (on-target mutagenesis) and safety (lack of off-target mutagenesis) of genome-editing therapy before it can be used in patients.We used a clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated (Cas) 9 genome-editing system to target the human PCSK9 gene in chimeric liver-humanized mice bearing human hepatocytes. We demonstrated high on-target mutagenesis (approaching 50%), greatly reduced blood levels of human PCSK9 protein, and minimal off-target mutagenesis.This work yields important information on the efficacy and safety of CRISPR-Cas9 therapy targeting the human PCSK9 gene in human hepatocytes in vivo, and it establishes humanized mice as a useful platform for the preclinical assessment of applications of somatic in vivo genome editing.2016-01-01T00:00:00Z2016 May2020-11-01T08:00:18Z2019-03-27T02:12:41ZS-EPMC48500822694102010.1161/ATVBAHA.116.30722710.1161/atvbaha.116.307227