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Reply to: Questions about the role of P3HT nanoparticles in retinal stimulation

Nature Nanotechnology volume 16, pages 1333–1336 (2021)Cite this article

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The Original Article was published on 09 December 2021

replying to Palanker et al. Nature Nanotechnology https://doi.org/10.1038/s41565-021-01044-6 (2021)

In the Maya-Vetencourt et al. article1,2, we found that the in vivo microinjection of P3HT nanoparticles (P3HT-NPs) promotes a sustained (up to 8 months) visual restoration in an albino model of retinitis pigmentosa (pink-eyed Royal College of Surgeons (RCS) rat) that loses the bulk of retinal photoreceptors between 2 and 3 months of age3. We observed that: (1) in all dystrophic RCS rats, irrespective of the treatment, the number of photoreceptors spared from degeneration is extremely low, which rules out potential trophic effects that might confound the results, (2) P3HT-NPs rescue visual activities in a physiological range of luminances and (3) P3HT-NPs expand the light sensitivity to the red region of the spectrum to which healthy albino rats are poorly sensitive4,5,6. The novelty of our approach is the seamless interface that can be established by the organic semiconductor with the biological matter. It is a soft matter with a soft-matter interface, in which ionic, as well as electronic, transports are available. Thus, the in vivo condition is essential to fully establish such an interface and for it to function.

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Fig. 1: P3HT-NPs stimulate retinal neurons.
Fig. 2: P3HT-NPs extends the spectral sensitivity of RCS retina.

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Acknowledgements

The research on NPs was supported by Fondazione Cariplo (project 2018-0505), H2020-MSCA-ITN 2019 ‘Entrain Vision’ (project 861423) and EuroNanoMed3 (project 2019-132).

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Authors and Affiliations

  1. Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, Genova, Italy

    Fabio Benfenati

  2. IRCCS Ospedale Policlinico San Martino, Genova, Italy

    Fabio Benfenati

  3. Center for Nanoscience and Technology, Istituto Italiano di Tecnologia, Milan, Italy

    Guglielmo Lanzani

  4. Department of Physics, Politecnico di Milano, Milan, Italy

    Guglielmo Lanzani

Authors
  1. Fabio Benfenati
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  2. Guglielmo Lanzani
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Contributions

F.B. and G.L. co-wrote the letter on behalf of all the authors of the original article.

Corresponding author

Correspondence to Fabio Benfenati.

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Competing interests

G.L. and F.B. are consultants of Novavido Srl, a company that develops organic retinal prostheses. The P3HT-NP technology is the subject of US patent application US 16/005,248 ‘Eye-injectable polymeric nanoparticles and method of use therefor’ by Istituto Italiano di Tecnologia and Ospedale Sacrocuore Don Calabria, which is licensed to Novavido Srl.

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Peer review information Nature Nanotechnology thanks the anonymous reviewers for their contribution to the peer review of this work.

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Benfenati, F., Lanzani, G. Reply to: Questions about the role of P3HT nanoparticles in retinal stimulation. Nat. Nanotechnol. 16, 1333–1336 (2021). https://doi.org/10.1038/s41565-021-01043-7

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