Abstract
Glycogen storage disease type Ia (GSD Ia) is caused by a deficiency of glucose-6-phosphatase (G6Pase) in the liver leading to lethal hypoglycemia. Gene therapy with adeno-associated virus (AAV) vectors encoding G6Pase fails to stably treat GSD Ia early in life. We evaluated genome editing in 12-day-old infant mice with GSD Ia using 2 AAV vectors, one containing Cas9 from Streptococcus pyogenes and a second Donor vector that expresses a guide RNA and a G6PC transgene. Gene therapy with the Donor vector only was compared with genome editing using both Donor and CRISPR vectors. Treatment with genome editing (total vector dose 0.2 × 1013 to 2 × 1013 vector genomes/kg) and bezafibrate (to stimulate autophagy) was efficacious, as assessed by hypoglycemia prevention and the frequency of transgene integration, which correlated with improved survival. This therapy achieved 5.9% chromosomal transgene integration through homology-directed repair, which surpassed a threshold to prevent long-term hepatic complications. No integration was detected in the absence of the CRISPR vector. Importantly for safety, CRISPR vector genomes were depleted, and no intact, integrated CRISPR genomes were detected by long-read sequencing. Thus, genome editing warrants further development as a potentially stable treatment for human infants with GSD Ia.
Authors
Benjamin Arnson, Ekaterina Ilich, Troy von Beck, Songtao Li, Elizabeth D. Brooks, Dorothy Gheorghiu, Gordon He, Matthew Weinrub, Sze Ying Chan, Hye-Ri Kang, David Courtney, Jeffrey I. Everitt, Bryan R. Cullen, Dwight D. Koeberl
This file is in Adobe Acrobat (PDF) format. If you have not installed and configured the Adobe Acrobat Reader on your system.
Having trouble reading a PDF?
PDFs are designed to be printed out and read, but if you prefer to read them online, you may find it easier if you increase the view size to 125%.
Having trouble saving a PDF?
Many versions of the free Acrobat Reader do not allow Save. You must instead save the PDF from the JCI Online page you downloaded it from. PC users: Right-click on the Download link and choose the option that says something like "Save Link As...". Mac users should hold the mouse button down on the link to get these same options.
Having trouble printing a PDF?
- Try printing one page at a time or to a newer printer.
- Try saving the file to disk before printing rather than opening it "on the fly." This requires that you configure your browser to "Save" rather than "Launch Application" for the file type "application/pdf", and can usually be done in the "Helper Applications" options.
- Make sure you are using the latest version of Adobe's Acrobat Reader.
