Extended field-of-view ultrathin microendoscopes for high-resolution two-photon imaging with minimal invasiveness

Abstract

Imaging neuronal activity with high and homogeneous spatial resolution across the field-of-view (FOV) and limited invasiveness in deep brain regions is fundamental for the progress of neuroscience, yet is a major technical challenge. We achieved this goal by correcting optical aberrations in gradient index lens-based ultrathin (≤ 500 µm) microendoscopes using aspheric microlenses generated through 3D-microprinting. Corrected microendoscopes had extended FOV (eFOV) with homogeneous spatial resolution for two-photon fluorescence imaging and required no modification of the optical set-up. Synthetic calcium imaging data showed that, compared to uncorrected endoscopes, eFOV-microendoscopes led to improved signal-to-noise ratio and more precise evaluation of correlated neuronal activity. We experimentally validated these predictions in awake head-fixed mice. Moreover, using eFOV-microendoscopes we demonstrated cell-specific encoding of behavioral state-dependent information in distributed functional subnetworks in a primary somatosensory thalamic nucleus. eFOV-microendoscopes are, therefore, small-cross-section ready-to-use tools for deep two-photon functional imaging with unprecedentedly high and homogeneous spatial resolution.

Data availability

The datasets shown in Figures 4, 6, 7 and corresponding figure supplements are available at:https://data.mendeley.com/datasets/wm6c5wzs4c/draft?a=56f1660e-a036-40ee-83ef-458dc2457b6aThe software used in this paper to generate and analyze artificial t-series is available at: https://github.com/moni90/eFOV_microendoscopes_simNumerical data for graphs represented in figures 3-7, figure 2-figure supplement 2-4, figure 3-figure supplement 4, figure 4-figure supplement 1-2 are provided as source data.

The following data sets were generated

Article and author information

Author details

  1. Andrea Antonini

    Department of Neuroscience and Brain Technologies, Italian Institute of Technology, Genova, Italy
    Competing interests
    The authors declare that no competing interests exist.
  2. Andrea Sattin

    Department of Neuroscience and Brain Technologies, Italian Institute of Technology, Genova, Italy
    Competing interests
    The authors declare that no competing interests exist.
  3. Monica Moroni

    CNCS, Italian Institute of Technology, ROVERETO, Italy
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1852-7217
  4. Serena Bovetti

    Department of Neuroscience and Brain Technologies, Italian Institute of Technology, Genova, Italy
    Competing interests
    The authors declare that no competing interests exist.
  5. Claudio Moretti

    Department of Neuroscience and Brain Technologies, Italian Institute of Technology, Genova, Italy
    Competing interests
    The authors declare that no competing interests exist.
  6. Francesca Succol

    Department of Neuroscience and Brain Technologies, Italian Institute of Technology, Genova, Italy
    Competing interests
    The authors declare that no competing interests exist.
  7. Angelo Forli

    Department of Neuroscience and Brain Technologies, Italian Institute of Technology, Genova, Italy
    Competing interests
    The authors declare that no competing interests exist.
  8. Dania Vecchia

    Department of Neuroscience and Brain Technologies, Italian Institute of Technology, Genova, Italy
    Competing interests
    The authors declare that no competing interests exist.
  9. Vijayakumar P Rajamanickam

    BESE, KAUST, Thuwal, Saudi Arabia
    Competing interests
    The authors declare that no competing interests exist.
  10. Andrea Bertoncini

    BESE, KAUST, Thuwal, Saudi Arabia
    Competing interests
    The authors declare that no competing interests exist.
  11. Stefano Panzeri

    Center for Neuroscience and Cognitive Systems, Italian Institute of Technology, Rovereto, Italy
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1700-8909
  12. Carlo Liberale

    BESE, KAUST, Thuwal, Saudi Arabia
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5653-199X
  13. Tommaso Fellin

    Department of Neuroscience and Brain Technologies, Italian Institute of Technology, Genova, Italy
    For correspondence
    tommaso.fellin@iit.it
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2718-7533

Funding

European Research Council (NEURO-PATTERNS)

  • Tommaso Fellin

IIT interdisciplinary grant

  • Tommaso Fellin

IIT interdisciplinary grant

  • Carlo Liberale

KAUST (BAS/1/1064-01-01)

  • Carlo Liberale

NIH Brain Initiative (NS090576)

  • Tommaso Fellin

NIH Brain Initiative (NS107464)

  • Tommaso Fellin

NIH Brain Initiative (NS107464)

  • Stefano Panzeri

NIH Brain Initiative (NS109961)

  • Stefano Panzeri

FP7 (DESIRE)

  • Tommaso Fellin

FIRB (RBAP11X42L)

  • Tommaso Fellin

Flag-Era JTC Human Brain Project (SLOW-DYN)

  • Tommaso Fellin

Flag-Era JTC Human Brain Project (SLOW-DYN)

  • Stefano Panzeri

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Ethics

Animal experimentation: Experimental procedures involving animals have been approved by the Istituto Italiano di Tecnologia Animal Health Regulatory Committee, by the National Council on Animal Care of the Italian Ministry of Health (authorization # 1134/2015-PR, # 689/2018-PR) and carried out according to the National legislation (D.Lgs. 26/2014) and to the legislation of the European Communities Council Directive (European Directive 2010/63/EU).

Reviewing Editor

  1. Ryohei Yasuda, Max Planck Florida Institute for Neuroscience, United States

Publication history

  1. Received: May 13, 2020
  2. Accepted: October 12, 2020
  3. Accepted Manuscript published: October 13, 2020 (version 1)
  4. Accepted Manuscript updated: October 15, 2020 (version 2)
  5. Version of Record published: November 24, 2020 (version 3)

Copyright

© 2020, Antonini et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Andrea Antonini
  2. Andrea Sattin
  3. Monica Moroni
  4. Serena Bovetti
  5. Claudio Moretti
  6. Francesca Succol
  7. Angelo Forli
  8. Dania Vecchia
  9. Vijayakumar P Rajamanickam
  10. Andrea Bertoncini
  11. Stefano Panzeri
  12. Carlo Liberale
  13. Tommaso Fellin
(2020)
Extended field-of-view ultrathin microendoscopes for high-resolution two-photon imaging with minimal invasiveness
eLife 9:e58882.
https://doi.org/10.7554/eLife.58882

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