Dataset Information

Efficacy of adeno-associated virus gene therapy in a MNGIE murine model enhanced by chronic exposure to nucleosides.

ABSTRACT: Background: Preclinical studies have shown that gene therapy is a feasible approach to treat mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). However, the genetic murine model of the disease (Tymp/Upp1 double knockout, dKO) has a limited functional phenotype beyond the metabolic imbalances, and so the studies showing efficacy of gene therapy have relied almost exclusively on demonstrating correction of the biochemical phenotype. Chronic oral administration of thymidine (dThd) and deoxyuridine (dUrd) to dKO mice deteriorates the phenotype of the animals, providing a better model to test therapy approaches.

Methods: dKO mice were treated with both dThd and dUrd in drinking water from weaning until the end of the study. At 8 - 11 weeks of age, mice were treated with several doses of adeno-associated virus (AAV) serotype 8 vector carrying the human TYMP coding sequence under the control of different liver-specific promoters (TBG, AAT, or HLP). The biochemical profile and functional phenotype were studied over the life of the animals.

Findings: Nucleoside exposure resulted in 30-fold higher plasma nucleoside levels in dKO mice compared with non-exposed wild type mice. AAV-treatment provided elevated TP activity in liver and lowered systemic nucleoside levels in exposed dKO mice. Exposed dKO mice had enlarged brain ventricles (assessed by magnetic resonance imaging) and motor impairment (rotarod test); both were prevented by AAV treatment. Among all promoters tested, AAT showed the best efficacy.

Interpretation: Our results show that AAV-mediated gene therapy restores the biochemical homeostasis in the murine model of MNGIE and, for the first time, demonstrate that this treatment improves the functional phenotype.

Funding: This work was funded in part by the Spanish Instituto de Salud Carlos III, and the Generalitat de Catalunya. The disclosed funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

SUBMITTER: Vila-Julia F

PROVIDER: S-EPMC7689515 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Efficacy of adeno-associated virus gene therapy in a MNGIE murine model enhanced by chronic exposure to nucleosides.

Vila-Julià Ferran F Cabrera-Pérez Raquel R Cámara Yolanda Y Molina-Berenguer Miguel M Lope-Piedrafita Silvia S Hirano Michio M Mingozzi Federico F Torres-Torronteras Javier J Martí Ramon R

EBioMedicine 20201121

<h4>Background</h4>Preclinical studies have shown that gene therapy is a feasible approach to treat mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). However, the genetic murine model of the disease (Tymp/Upp1 double knockout, dKO) has a limited functional phenotype beyond the metabolic imbalances, and so the studies showing efficacy of gene therapy have relied almost exclusively on demonstrating correction of the biochemical phenotype. Chronic oral administration of thymidine (dThd ...[more]

PMID: 33232869

Similar Datasets

Project description:Severe inherited retinal diseases, such as retinitis pigmentosa and Leber congenital amaurosis, are caused by mutations in genes preferentially expressed in photoreceptors. While adeno-associated virus (AAV)-mediated gene transfer can correct retinal pigment epithelium (RPE) defects in animal models, approaches for the correction of photoreceptor-specific diseases are less efficient. We evaluated the ability of novel AAV serotypes (AAV2/7, AAV2/8, AAV2/9, AAV2rh.43, AAV2rh.64R1, and AAV2hu.29R) in combination with constitutive or photoreceptor-specific promoters to improve photoreceptor transduction, a limiting step in photoreceptor rescue. Based on a qualitative analysis, all AAV serotypes tested efficiently transduce the RPE as well as rod and cone photoreceptors after subretinal administration in mice. Interestingly, AAV2/9 efficiently transduces Müller cells. To compare photoreceptor transduction from different AAVs and promoters in both a qualitative and quantitative manner, we designed a strategy based on the use of a bicistronic construct expressing both enhanced green fluorescent protein and luciferase. We found that AAV2/8 and AAV2/7 mediate six- to eightfold higher levels of in vivo photoreceptor transduction than AAV2/5, considered so far the most efficient AAV serotype for photoreceptor targeting. In addition, following subretinal administration of AAV, the rhodopsin promoter allows significantly higher levels of photoreceptor expression than the other ubiquitous or photoreceptor-specific promoters tested. Finally, we show that AAV2/7, AAV2/8, and AAV2/9 outperform AAV2/5 following ex vivo transduction of retinal progenitor cells differentiated into photoreceptors. We conclude that AAV2/7 or AAV2/8 and the rhodopsin promoter provide the highest levels of photoreceptor transduction both in and ex vivo and that this may overcome the limitation to therapeutic success observed so far in models of inherited severe photoreceptor diseases.

Dataset Information

Efficacy of adeno-associated virus gene therapy in a MNGIE murine model enhanced by chronic exposure to nucleosides.

Publications

Efficacy of adeno-associated virus gene therapy in a MNGIE murine model enhanced by chronic exposure to nucleosides.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets