Intralingual and Intrapleural AAV Gene Therapy Prolongs Survival in a SOD1 ALS Mouse Model

Allison M Keeler; Marina Zieger; Carson Semple; Logan Pucci; Alessandra Veinbachs; Robert H Brown Jr; Christian Mueller; Mai K ElMallah

doi:10.1016/j.omtm.2019.12.007

Intralingual and Intrapleural AAV Gene Therapy Prolongs Survival in a SOD1 ALS Mouse Model

Mol Ther Methods Clin Dev. 2019 Dec 24:17:246-257. doi: 10.1016/j.omtm.2019.12.007. eCollection 2020 Jun 12.

Authors

Allison M Keeler^{1

2

3}, Marina Zieger^{1

2

3}, Carson Semple³, Logan Pucci⁴, Alessandra Veinbachs³, Robert H Brown Jr^{3

5}, Christian Mueller^{2

3}, Mai K ElMallah^{1

2

3

4}

Affiliations

¹ Division of Pulmonary Medicine, University of Massachusetts Medical School, Worcester, MA 01655, USA.
² Department of Pediatrics, University of Massachusetts Medical School, Worcester, MA 01655, USA.
³ Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA 01655, USA.
⁴ Department of Pediatrics, Duke University, Durham, NC 27710, USA.
⁵ Department of Neurology, University of Massachusetts Medical School, Worcester, MA 01655, USA.

Abstract

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that results in death from respiratory failure. No cure exists for this devastating disease, but therapy that directly targets the respiratory system has the potential to prolong survival and improve quality of life in some cases of ALS. The objective of this study was to enhance breathing and prolong survival by suppressing superoxide dismutase 1 (SOD1) expression in respiratory motor neurons using adeno-associated virus (AAV) expressing an artificial microRNA targeting the SOD1 gene. AAV-miR^SOD1 was injected in the tongue and intrapleural space of SOD1^G93A mice, and repetitive respiratory and behavioral measurements were performed until the end stage. Robust silencing of SOD1 was observed in the diaphragm and tongue as well as systemically. Silencing of SOD1 prolonged survival by approximately 50 days, and it delayed weight loss and limb weakness in treated animals compared to untreated controls. Histologically, there was preservation of the neuromuscular junctions in the diaphragm as well as the number of axons in the phrenic and hypoglossal nerves. Although SOD1 suppression improved breathing and prolonged survival, it did not ameliorate the restrictive lung phenotype. Suppression of SOD1 expression in motor neurons that underlie respiratory function prolongs survival and enhances breathing until the end stage in SOD1^G93A ALS mice.

Abstract

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