Gene therapy restores dopamine transporter expression and ameliorates pathology in iPSC and mouse models of infantile parkinsonism

Sci Transl Med. 2021 May 19;13(594):eaaw1564. doi: 10.1126/scitranslmed.aaw1564. | PubMed

Joanne Ng^1,2, Serena Barral³, Carmen De La Fuente Barrigon⁴, Gabriele Lignani⁵, Fatma A Erdem^2,6, Rebecca Wallings⁷, Riccardo Privolizzi^1,2, Giada Rossignoli², Haya Alrashidi⁴, Sonja Heasman², Esther Meyer², Adeline Ngoh², Simon Pope⁸, Rajvinder Karda¹, Dany Perocheau¹, Julien Baruteau^1,4, Natalie Suff^1,9, Juan Antinao Diaz¹, Stephanie Schorge^5,10, Jane Vowles¹¹, Lucy R Marshall¹², Sally A Cowley¹¹, Sonja Sucic⁶, Michael Freissmuth⁶, John R Counsell¹³, Richard Wade-Martins⁷, Simon J R Heales^4,8, Ahad A Rahim¹⁰, Maximilien Bencze^13,14, Simon N Waddington^15,16, Manju A Kurian^2,17

1. Gene Transfer Technology Group, EGA-Institute for Women's Health, University College London, London, WC1E 6HX, UK.
2. Developmental Neurosciences, Zayed Centre for Research into Rare Disease in Children, GOS-Institute of Child Health, University College London, London, WC1N 1DZ, UK.
3. Developmental Neurosciences, Zayed Centre for Research into Rare Disease in Children, GOS-Institute of Child Health, University College London, London, WC1N 1DZ, UK. s.waddington@ucl.ac.uk s.barral@ucl.ac.uk.
4. Genetics and Genomic Medicine, GOS-Institute of Child Health, University College London, London, WC1N 1EH, UK.
5. Clinical and Experimental Epilepsy, Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK.
6. Institute of Pharmacology and Gaston H. Glock Laboratories for Exploratory Drug Research, Centre of Physiology and Pharmacology, Medical University of Vienna, 1090 Vienna, Austria.
7. Oxford Parkinson's Disease Centre, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, OX1 3PT, UK.
8. Neurometabolic Unit, National Hospital for Neurology and Neurosurgery, Queen Square, London, WC1N 3BG, UK.
9. Department of Women and Children's Health, King's College London, London, WC2R 2LS, UK.
10. Pharmacology, School of Pharmacy, University College London, London, WC1N 1AX, UK.
11. James Martin Stem Cell Facility, Sir William Dunn School of Pathology, University of Oxford, Oxford, OX1 3RE, UK.
12. Infection, Immunity, Inflammation, GOS-Institute of Child Health, University College London, London, WC1N 1EH, UK.
13. Developmental Neurosciences, GOS-Institute of Child Health, University College London, London, WC1N 1EH, UK.
14. University Paris Est Creteil, INSERM, IMRB, 94000 Creteil, France.
15. Gene Transfer Technology Group, EGA-Institute for Women's Health, University College London, London, WC1E 6HX, UK. s.waddington@ucl.ac.uk s.barral@ucl.ac.uk.
16. Wits/SAMRC Antiviral Gene Therapy Research Unit, Faculty of Health Sciences, University of the Witwatersrand, 2193 Johannesburg, South Africa.
17. Department of Neurology, Great Ormond Street Hospital for Children, London, WC1N 3JH, UK.

Abstract

Most inherited neurodegenerative disorders are incurable, and often only palliative treatment is available. Precision medicine has great potential to address this unmet clinical need. We explored this paradigm in dopamine transporter deficiency syndrome (DTDS), caused by biallelic loss-of-function mutations in SLC6A3, encoding the dopamine transporter (DAT). Patients present with early infantile hyperkinesia, severe progressive childhood parkinsonism, and raised cerebrospinal fluid dopamine metabolites. The absence of effective treatments and relentless disease course frequently leads to death in childhood. Using patient-derived induced pluripotent stem cells (iPSCs), we generated a midbrain dopaminergic (mDA) neuron model of DTDS that exhibited marked impairment of DAT activity, apoptotic neurodegeneration associated with TNFα-mediated inflammation, and dopamine toxicity. Partial restoration of DAT activity by the pharmacochaperone pifithrin-μ was mutation-specific. In contrast, lentiviral gene transfer of wild-type human SLC6A3 complementary DNA restored DAT activity and prevented neurodegeneration in all patient-derived mDA lines. To progress toward clinical translation, we used the knockout mouse model of DTDS that recapitulates human disease, exhibiting parkinsonism features, including tremor, bradykinesia, and premature death. Neonatal intracerebroventricular injection of human SLC6A3 using an adeno-associated virus (AAV) vector provided neuronal expression of human DAT, which ameliorated motor phenotype, life span, and neuronal survival in the substantia nigra and striatum, although off-target neurotoxic effects were seen at higher dosage. These were avoided with stereotactic delivery of AAV2.SLC6A3 gene therapy targeted to the midbrain of adult knockout mice, which rescued both motor phenotype and neurodegeneration, suggesting that targeted AAV gene therapy might be effective for patients with DTDS.

Presented By Joanne Ng | ORCID iD