Amyotrophic lateral sclerosis (ALS) is a progressive, untreatable, uniformly fatal motor neuron disorder that sometimes develops concurrently with frontotemporal dementia (FTD). ALS is encountered in both sporadic (SALS) and familial (FALS) forms;about 10% of cases are transmitted as autosomal dominant traits. The cause of sporadic ALS is not known. Recently it was discovered that about 30-50% of FALS cases are caused by expansions of a non-coding hexanucleotide G4C2 expansion in the gene C9ORF72. These expansions are also detected in 10-20% of familial FTD, 10% of sporadic FTD and in ~5% of SALS. These statistics define the C9ORF72 G4C2 expansion as the most common cause of ALS. In the present study, we propose to use rAAV type Rh10 to introduce a microRNA to silence expression of the transcripts of C9ORF72 that harbor the offending G4C2 expansion.
In Aim 1, we will screen, identify and optimize potential miRNAs in vitro.
In Aim 2, we will further characterize the phenotype of our novel C9ORF72mutant transgenic mouse and investigate use of rAAVRh10-C9miRs to silencing the mutant C9 transgene and thereby mitigate the phenotype in this mouse.
In Aim 3 we will investigate delivery and efficacy of the rAAVRh10-C9miRs in a non- human primate model as first step to translating this therapy to clinical application. Relevance: We believe that these studies will be highly relevant for several reasons. (1) There is a compelling unmet need for effective ALS treatments;this project focuses on the most common form of FALS, with applicability as well to some cases of SALS and FTD. (2) This investigation will develop the use of intrathecal rAAVRh10 as a gene therapy vector for the CNS;the intrathecal route is advantageous, permitting widespread delivery within the CNS with doses that are an order-of-magnitude lower than are required via intravenous delivery;and minimizing peripheral exposure to virus. (3) rAAV has not been used in human neurodegenerative disorders. The platform we propose to develop here should have broad applicability across a breadth of neurological disorders.

Public Health Relevance

Amyotrophic lateral sclerosis and frontotemporal dementia are fatal neurodegenerative disorders for which no effective treatments are available. Recently, a genetic expansion in a gene termed C9ORF72 was found to be the leading genetic cause for these diseases. The mutant C9ORF72 gene causes accumulation of toxic by-products in neuronal cells, leading to neurodegeneration. We have created a mouse model that harbors this same mutation which also results in the accumulation of the mutant C9ORF72 by products. We propose to use this mouse along with patient cell lines to test whether inhibitory small RNA molecules can suppress toxicity of the mutant C9ORF72. To test our hypothesis, we inject mice with viral vectors that express inhibitory small RNA molecules that target C9ORF7. In the mouse model of the disease we can then determine if small RNA molecules are able to suppress the toxicity associated with the mutant C9ORF72. Finally we will test these therapies in a primate model in order to optimize the viral vectors for a future clinical trial.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
1R01NS088689-01
Application #
8767751
Study Section
Therapeutic Approaches to Genetic Diseases (TAG)
Program Officer
Gubitz, Amelie
Project Start
2014-07-01
Project End
2018-04-30
Budget Start
2014-07-01
Budget End
2015-04-30
Support Year
1
Fiscal Year
2014
Total Cost
Indirect Cost
Name
University of Massachusetts Medical School Worcester
Department
Neurology
Type
Schools of Medicine
DUNS #
City
Worcester
State
MA
Country
United States
Zip Code
01655
Mordes, Daniel A; Prudencio, Mercedes; Goodman, Lindsey D et al. (2018) Dipeptide repeat proteins activate a heat shock response found in C9ORF72-ALS/FTLD patients. Acta Neuropathol Commun 6:55
Borel, Florie; Sun, Huaming; Zieger, Marina et al. (2018) Editing out five Serpina1 paralogs to create a mouse model of genetic emphysema. Proc Natl Acad Sci U S A 115:2788-2793
Gendron, Tania F; Petrucelli, Leonard (2018) Disease Mechanisms of C9ORF72 Repeat Expansions. Cold Spring Harb Perspect Med 8:
Ebbert, Mark T W; Farrugia, Stefan L; Sens, Jonathon P et al. (2018) Long-read sequencing across the C9orf72 'GGGGCC' repeat expansion: implications for clinical use and genetic discovery efforts in human disease. Mol Neurodegener 13:46
Wang, Zi-Fu; Ursu, Andrei; Childs-Disney, Jessica L et al. (2018) The Hairpin Form of r(G4C2)exp in c9ALS/FTD Is Repeat-Associated Non-ATG Translated and a Target for Bioactive Small Molecules. Cell Chem Biol :
White, Matthew A; Kim, Eosu; Duffy, Amanda et al. (2018) TDP-43 gains function due to perturbed autoregulation in a Tardbp knock-in mouse model of ALS-FTD. Nat Neurosci 21:552-563
Lee, Chris W; Stankowski, Jeannette N; Chew, Jeannie et al. (2017) The lysosomal protein cathepsin L is a progranulin protease. Mol Neurodegener 12:55
Prudencio, Mercedes; Gonzales, Patrick K; Cook, Casey N et al. (2017) Repetitive element transcripts are elevated in the brain of C9orf72 ALS/FTLD patients. Hum Mol Genet 26:3421-3431
Gernoux, Gwladys; Wilson, James M; Mueller, Christian (2017) Regulatory and Exhausted T Cell Responses to AAV Capsid. Hum Gene Ther 28:338-349
Stoica, Lorelei; Keeler, Allison M; Xiong, Lang et al. (2017) Restrictive Lung Disease in the Cu/Zn Superoxide-Dismutase 1 G93A Amyotrophic Lateral Sclerosis Mouse Model. Am J Respir Cell Mol Biol 56:405-408

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