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Cell replacement therapies for neurodegenerative disease have focused on transplantation of the cell types affected by the pathological process. Here we describe an alternative strategy for Parkinson's disease in which dopamine neurons are generated by direct conversion of astrocytes. Using three transcription factors, NEUROD1, ASCL1 and LMX1A, and the microRNA miR218, collectively designated NeAL218, we reprogram human astrocytes in vitro, and mouse astrocytes in vivo, into induced dopamine neurons (iDANs). Reprogramming efficiency in vitro is improved by small molecules that promote chromatin remodeling and activate the TGFβ, Shh and Wnt signaling pathways. The reprogramming efficiency of human astrocytes reaches up to 16%, resulting in iDANs with appropriate midbrain markers and excitability. In a mouse model of Parkinson's disease, NeAL218 alone reprograms adult striatal astrocytes into iDANs that are excitable and correct some aspects of motor behavior in vivo, including gait impairments. With further optimization, this approach may enable clinical therapies for Parkinson's disease by delivery of genes rather than cells.

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  • 19 April 2017

    In the version of this article initially published, in the paragraph before the Discussion, the sentence that read in part “…the very high levels of DA that are required in the synapses to induce circling behavior…” should have read “…the very high levels of DA that are required in the synapses to reduce circling behavior…” The error has been corrected for the print, PDF and HTML versions of this article.


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We thank the members of the Arenas laboratory for help and suggestions; J. Söderlund and A. Nanni for technical and secretarial assistance; and the SciLife National Genomic Infrastructure (Stockholm) for RNA sequencing. This work was supported by grants from the Swedish Research Council (VR: DBRM, 2011-3116/3318 and 2016-01526), Swedish Foundation for Strategic Research (SRL), EU (NeuroStemcellRepair and DDPDgenes), Karolinska Institutet, Strat Regen, Hjärnfonden (FO2013:0108, FO2015:0202) and Cancerfonden (CAN 2016/572) to E.A.; VR (2012-13482 and 2015-02886), StratNeuro, Parkinsonfonden, Hjärnfonden and KI/NIH to G.F.; VR (2013-3080), EU (PAINCAGE), Hjärnfonden, NovoNordisk Foundation and the European Research Council (“Secret Cells”) to T.H.; and New York Stem Cell Foundation, NIH and CIRM to M.W. Support to P.R.d.V.C. was provided by VR (524-2011-962) and EMBO (ALTF583-2011); to R.A.R. by EMBO (ALTF596-2014) and Marie Curie (EMBOCOFUND2012, GA-2012-600394); to D.M. by KI and by the Brasilian Ministry of Education (CAPES) and to E.M.-M. by the Spanish Ministry of Education (José Castillejo). The authors acknowledge support from Science for Life Laboratory, the Knut and Alice Wallenberg Foundation, the National Genomics Infrastructure funded by the Swedish Research Council, and Uppsala Multidisciplinary Center for Advanced Computational Science for assistance with massively parallel sequencing and access to the UPPMAX computational infrastructure.

Author information


  1. Laboratory of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.

    • Pia Rivetti di Val Cervo
    • , Elisa Martín-Montañez
    • , Enrique M Toledo
    • , Gioele La Manno
    • , Sara Padrell Sánchez
    • , Sten Linnarsson
    •  & Ernest Arenas
  2. Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria.

    • Roman A Romanov
    • , Christian Pifl
    •  & Tibor Harkany
  3. Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.

    • Roman A Romanov
    • , Giada Spigolon
    • , Débora Masini
    • , Michael Feyder
    • , Tibor Harkany
    •  & Gilberto Fisone
  4. Department of Pharmacology, Faculty of Medicine, Biomedical Research Institute of Malaga (IBIMA), Malaga University, Malaga, Spain.

    • Elisa Martín-Montañez
  5. Institute for Stem Cell Biology and Regenerative Medicine, Stanford University, Stanford, California, USA.

    • Yi-Han Ng
    •  & Marius Wernig


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E.A. and P.R.d.V.C. conceived the experiments and wrote the manuscript; P.R.d.V.C., R.A.R., G.S., D.M., E.M.-M., E.M.T., G.L.M., M.F., C.P., Y.-H.N. and S.P.S. performed the experiments; S. L., M.W., T.H., G.F. and E.A. provided expertise and funding.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Ernest Arenas.

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