UMMS Affiliation
Department of Medicine; Horae Gene Therapy Center; RNA Therapeutics Institute; Department of Pediatrics, Division of Pulmonology
Publication Date
2017-06-16
Document Type
Article
Disciplines
Genetics and Genomics | Nervous System Diseases | Therapeutics
Abstract
Huntington's disease is a devastating, incurable neurodegenerative disease affecting up to 12 per 100,000 patients worldwide. The disease is caused by a mutation in the Huntingtin (Htt) gene. There is interest in reducing mutant Huntingtin by targeting it at the mRNA level, but the maximum tolerable dose and long-term effects of such a treatment are unknown. Using a self-complementary AAV9 vector, we delivered a mir-155-based artificial miRNA under the control of the chicken beta-actin or human U6 promoter. In mouse brain, the artificial miRNA reduced the human huntingtin mRNA by 50%. The U6, but not the CbetaA promoter, produced the artificial miRNA at supraphysiologic levels. Embedding the antisense strand in a U6-mir-30 scaffold reduced expression of the antisense strand but increased the sense strand. In mice treated with scAAV9-U6-mir-155-HTT or scAAV9-CbetaA-mir-155-HTT, activated microglia were present around the injection site 1 month post-injection. Six months post-injection, mice treated with scAAV9-CbetaA-mir-155-HTT were indistinguishable from controls. Those that received scAAV9-U6-mir-155-HTT showed behavioral abnormalities and striatal damage. In conclusion, miRNA backbone and promoter can be used together to modulate expression levels and strand selection of artificial miRNAs, and in brain, the CbetaA promoter can provide an effective and safe dose of a human huntingtin miRNA.
Keywords
AAV, HTT, Huntington’s disease, RNAi, gene therapy, huntingtin, miRNA, shRNA
DOI of Published Version
10.1016/j.omtn.2017.04.011
Source
Mol Ther Nucleic Acids. 2017 Jun 16;7:324-334. doi: 10.1016/j.omtn.2017.04.011. Epub 2017 Apr 14. Link to article on publisher's site
Journal/Book/Conference Title
Molecular therapy. Nucleic acids
Related Resources
PubMed ID
28624208
Repository Citation
Pfister EL, Chase KO, Sun H, Kennington LA, Conroy F, Johnson ES, Miller R, Borel F, Aronin N, Mueller C. (2017). Safe and Efficient Silencing with a Pol II, but Not a Pol lII, Promoter Expressing an Artificial miRNA Targeting Human Huntingtin. Pediatric Publications. https://doi.org/10.1016/j.omtn.2017.04.011. Retrieved from https://escholarship.umassmed.edu/peds_pp/152
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.