Extracellular vesicles (EVs) are membrane particles involved in the exchange of a broad range of bioactive molecules between cells and the microenvironment. Although it has been shown that cells can traffic metabolic enzymes via EVs, much remains to be elucidated with regard to their intrinsic metabolic activity. Accordingly, herein we assessed the ability of neural stem/progenitor cell (NSC)-derived EVs to consume and produce metabolites. Our metabolomics and functional analyses both revealed that EVs harbor L-asparaginase activity, catalyzed by the enzyme asparaginase-like protein 1 (Asrgl1). Critically, we show that Asrgl1 activity is selective for asparagine and is devoid of glutaminase activity. We found that mouse and human NSC EVs traffic Asrgl1. Our results demonstrate, for the first time, that NSC EVs function as independent metabolic units that are able to modify the concentrations of critical nutrients, with the potential to affect the physiology of their microenvironment.

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The authors thank F. Dazzi, C. Mauro, J. Smith and A. Tolkovsky for critically discussing the article. We are grateful to J. Muzard (iZON) for his help with the qNano. We acknowledge the technical assistance of I. Bicci, M. Davis, F. Gessler, G. Pluchino and B. Vega-Blanco. This work has received support from the Italian Multiple Sclerosis Association (AISM; grant 2010/R/31 and grant 2014/PMS/4 to S.P.); the Italian Ministry of Health (GR08-7 to S.P.); the European Research Council (ERC) under the ERC-2010-StG Grant agreement no. 260511-SEM_SEM; the Medical Research Council, the Engineering and Physical Sciences Research Council and the Biotechnology and Biological Sciences Research Council UK Regenerative Medicine Platform Hub “Acellular Approaches for Therapeutic Delivery” (MR/K026682/1 to S.P.); The Evelyn Trust (RG 69865 to S.P.); The Bascule Charitable Trust (RG 75149 to S.P.); and core support grant from the Wellcome Trust and Medical Research Council to the Wellcome Trust–MRC Cambridge Stem Cell Institute. N.I. was supported by a FEBS long-term fellowship. C.F., A.S.H., and E.G. were funded by the Medical Research Council, Core Fund SKAG006.

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Author notes

    • Nunzio Iraci

    Present address: Department of Biomedical and Biotechnological Sciences (BIOMETEC), University of Catania, Catania, Italy.

    • Nunzio Iraci
    •  & Edoardo Gaude

    These authors contributed equally to this work.


  1. Wellcome Trust–Medical Research Council Stem Cell Institute, Department of Clinical Neurosciences–Division of Stem Cell Neurobiology, and NIHR Biomedical Research Centre, University of Cambridge, Cambridge, UK.

    • Nunzio Iraci
    • , Tommaso Leonardi
    • , Chiara Cossetti
    • , Luca Peruzzotti-Jametti
    • , Joshua D Bernstock
    •  & Stefano Pluchino
  2. MRC Cancer Unit, University of Cambridge, Hutchison/MRC Research Centre, Cambridge Biomedical Campus, Cambridge, UK.

    • Edoardo Gaude
    • , Ana S H Costa
    •  & Christian Frezza
  3. European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Trust Genome Campus, Hinxton, Cambridge, UK.

    • Tommaso Leonardi
    • , Harpreet K Saini
    •  & Anton J Enright
  4. Stroke Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health (NINDS/NIH), Bethesda, Maryland, USA.

    • Joshua D Bernstock
  5. Stem Cells Laboratory, Cell Factory and Biobank, Azienda Ospedaliera 'Santa Maria', Terni, Italy.

    • Maurizio Gelati
  6. IRCCS Casa Sollievo della Sofferenza, Foggia, Italy.

    • Maurizio Gelati
    •  & Angelo Luigi Vescovi
  7. Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milano, Italy.

    • Angelo Luigi Vescovi
  8. Medical Research Council–Elsie Widdowson Laboratory, Cambridge, UK.

    • Carlos Bastos
    •  & Nuno Faria
  9. Department of Engineering, Electrical Engineering Division, University of Cambridge, Cambridge, UK.

    • Luigi G Occhipinti


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N.I., E.G., C.F. and S.P. conceived the study and designed the experiments; N.I., T.L., C.C., L.P.-J., J.D.B. and M.G. elucidated the trafficking of Asrgl1 into NSC EVs, and performed experiments including cell culture preparations, EV purification from media, tunable sensitive pulse sensing, western blots, RT and qPCR, vector production and generation of gain-of-function and loss-of-function tools; N.I., C.B. and N.F. performed nanoparticle tracking analysis; A.S.H.C. and E.G. performed the LC–MS metabolomic analyses; A.L.V., L.G.O., C.F. and S.P. provided key reagents and resources; N.I., E.G., A.S.H.C., T.L., H.K.S., A.J.E., C.F. and S.P. analyzed the data and interpreted and discussed the results; N.I., E.G., C.F. and S.P. prepared the figures and wrote and edited the manuscript; C.F. and S.P. supervised the research.

Competing interests

N.I., E.G., T.L., C.F. and S.P. are listed as inventors on a patent application related to the technology described in this work (European Patent application no. 16189525.5).

Corresponding authors

Correspondence to Christian Frezza or Stefano Pluchino.

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