Proof-of-concept gene editing for the murine model of inducible arginase-1 deficiency

Sin, Y. Y., Price, P. R., Ballantyne, L. L. and Funk, C. D. (2017) Proof-of-concept gene editing for the murine model of inducible arginase-1 deficiency. Scientific Reports, 7, 2585. (doi: 10.1038/s41598-017-02927-2) (PMID:28566761) (PMCID:PMC5451454)

Abstract

Arginase-1 deficiency in humans is a rare genetic disorder of metabolism resulting from a loss of arginase-1, leading to impaired ureagenesis, hyperargininemia and neurological deficits. Previously, we generated a tamoxifen-inducible arginase-1 deficient mouse model harboring a deletion of Arg1 exons 7 and 8 that leads to similar biochemical defects, along with a wasting phenotype and death within two weeks. Here, we report a strategy utilizing the Clustered, Regularly Interspaced, Short Palindromic Repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) system in conjunction with piggyBac technology to target and reincorporate exons 7 and 8 at the specific Arg1 locus in attempts to restore the function of arginase-1 in induced pluripotent stem cell (iPSC)-derived hepatocyte-like cells (iHLCs) and macrophages in vitro. While successful gene targeted repair was achieved, minimal urea cycle function was observed in the targeted iHLCs compared to adult hepatocytes likely due to inadequate maturation of the cells. On the other hand, iPSC-derived macrophages expressed substantial amounts of "repaired" arginase. Our studies provide proof-of-concept for gene-editing at the Arg1 locus and highlight the challenges that lie ahead to restore sufficient liver-based urea cycle function in patients with urea cycle disorders.

• Item Type: Articles
• Additional Information: This work was supported by a microgrant from the Rare Disease Foundation and the BC Children’s Hospital Foundation (BCCHF) (#18-19 to YYS). CDF is supported by the Canada Research Chairs program and the Canadian Institutes of Health Research (CIHR) (MOP-341036).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Sin, Dr Angie
• Authors: Sin, Y. Y., Price, P. R., Ballantyne, L. L., and Funk, C. D.
• College/School: College of Medical Veterinary and Life Sciences > School of Cardiovascular & Metabolic Health
• Journal Name: Scientific Reports
• Publisher: Nature Research
• ISSN: 2045-2322
• ISSN (Online): 2045-2322
• Copyright Holders: Copyright © 2017 The Authors
• First Published: First published in Scientific Reports 7: 2585
• Publisher Policy: Reproduced under a Creative Commons License