Potential conflict of interest: Nothing to report.
Treatment of phenylketonuria using minicircle-based naked-DNA gene transfer to murine liver
Article first published online: 29 JUL 2014
© 2014 by the American Association for the Study of Liver Diseases
Volume 60, Issue 3, pages 1035–1043, September 2014
How to Cite
Viecelli, H. M., Harbottle, R. P., Wong, S. P., Schlegel, A., Chuah, M. K., VandenDriessche, T., Harding, C. O. and Thöny, B. (2014), Treatment of phenylketonuria using minicircle-based naked-DNA gene transfer to murine liver. Hepatology, 60: 1035–1043. doi: 10.1002/hep.27104
Supported by grants from the Children's Research Center Zurich (to H.M.V.), the Swiss National Science Foundation (no. 310030-122045 to B.T.), the National Institute of Health (research grant no. 1R01HD057033 to C.O.H. and B.T.), and the Stiftung für wissenschaftliche Forschung der Universitüt Zürich (to B.T.).
- Issue published online: 25 AUG 2014
- Article first published online: 29 JUL 2014
- Accepted manuscript online: 28 FEB 2014 03:41AM EST
- Manuscript Accepted: 25 FEB 2014
- Manuscript Received: 12 JUL 2013
- The Children's Research Center Zurich (to H.M.V.)
- The Swiss National Science Foundation . Grant Number: 310030-122045 to B.T.
- The National Institute of Health . Grant Number: (research grant no. 1R01HD057033 to C.O.H. and B.T.)
- The Stiftung für wissenschaftliche Forschung der Universität Zürich (to B.T.)
Host immune response to viral vectors, persistence of nonintegrating vectors, and sustained transgene expression are among the major challenges in gene therapy. To overcome these hurdles, we successfully used minicircle (MC) naked-DNA vectors devoid of any viral or bacterial sequences for the long-term treatment of murine phenylketonuria, a model for a genetic liver defect. MC-DNA vectors expressed the murine phenylalanine hydroxylase (Pah) complementary DNA (cDNA) from a liver-specific promoter coupled to a de novo designed hepatocyte-specific regulatory element, designated P3, which is a cluster of evolutionary conserved transcription factor binding sites. MC-DNA vectors were subsequently delivered to the liver by a single hydrodynamic tail vein (HTV) injection. The MC-DNA vector normalized blood phenylalanine concomitant with reversion of hypopigmentation in a dose-dependent manner for more than 1 year, whereas the corresponding parental plasmid did not result in any phenylalanine clearance. MC vectors persisted in an episomal state in the liver consistent with sustained transgene expression and hepatic PAH enzyme activity without any apparent adverse effects. Moreover, 14-20% of all hepatocytes expressed transgenic PAH, and the expression was observed exclusively in the liver and predominately around pericentral areas of the hepatic lobule, while there was no transgene expression in periportal areas. Conclusion: This study demonstrates that MC technology offers an improved safety profile and has the potential for the genetic treatment of liver diseases. (Hepatology 2014;60:1035–1043)