Label-free imaging of M1 and M2 macrophage phenotypes in the human dermis in vivo using two-photon excited FLIM

  1. Marius Kröger
  2. Jörg Scheffel
  3. Evgeny A Shirshin
  4. Johannes Schleusener
  5. Martina C Meinke
  6. Jürgen Lademann
  7. Marcus Maurer
  8. Maxim E Darvin  Is a corresponding author
  1. Charité - Universitätsmedizin Berlin, Germany
  2. Lomonosov Moscow State University, Russian Federation

Abstract

Macrophages (ΜΦs) are important immune effector cells that promote (M1 ΜΦs) or inhibit (M2 ΜΦs) inflammation and are involved in numerous physiological and pathogenic immune responses. Their precise role and relevance, however, is not fully understood for lack of non-invasive quantification methods. Here, we show that two-photon excited fluorescence lifetime imaging (TPE-FLIM), a label-free non-invasive method, can visualize ΜΦs in the human dermis in vivo. We demonstrate in vitro that human dermal ΜΦs exhibit specific TPE-FLIM properties that distinguish them from the main components of the extracellular matrix and other dermal cells. We visualized ΜΦs, their phenotypes and phagocytosis in the skin of healthy individuals in vivo using TPE-FLIM. Additionally, machine learning identified M1 and M2 MФs with a sensitivity of 0.88±0.04 and 0.82±0.03 and a specificity of 0.89±0.03 and 0.90±0.03, respectively. In clinical research, TPE-FLIM can advance the understanding of the role of MФs in health and disease.

Data availability

The data have been deposited in Dryad:

The following data sets were generated
    1. Kröger M
    2. Darvin M
    (2021) Macrophage FLIM raw data
    Dryad Digital Repository, doi:10.5061/dryad.8gtht76q2.

Article and author information

Author details

  1. Marius Kröger

    Department of Dermatology, Venerology and Allergology, Charité - Universitätsmedizin Berlin, Berlin, Germany
    Competing interests
    The authors declare that no competing interests exist.
  2. Jörg Scheffel

    Department of Dermatology, Venerology and Allergology, Charité - Universitätsmedizin Berlin, Berlin, Germany
    Competing interests
    The authors declare that no competing interests exist.
  3. Evgeny A Shirshin

    Faculty of Physics, Lomonosov Moscow State University, Moscow, Russian Federation
    Competing interests
    The authors declare that no competing interests exist.
  4. Johannes Schleusener

    Department of Dermatology, Venerology and Allergology, Charité - Universitätsmedizin Berlin, Berlin, Germany
    Competing interests
    The authors declare that no competing interests exist.
  5. Martina C Meinke

    Department of Dermatology, Venerology and Allergology, Charité - Universitätsmedizin Berlin, Berlin, Germany
    Competing interests
    The authors declare that no competing interests exist.
  6. Jürgen Lademann

    Department of Dermatology, Venerology and Allergology, Charité - Universitätsmedizin Berlin, Berlin, Germany
    Competing interests
    The authors declare that no competing interests exist.
  7. Marcus Maurer

    Department of Dermatology, Venerology and Allergology, Charité - Universitätsmedizin Berlin, Berlin, Germany
    Competing interests
    The authors declare that no competing interests exist.
  8. Maxim E Darvin

    Department of Dermatology, Venerology and Allergology, Charité - Universitätsmedizin Berlin, Berlin, Germany
    For correspondence
    maxim.darvin@charite.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1075-1994

Funding

Foundation for Skin Physiology

  • Marius Kröger
  • Johannes Schleusener
  • Martina C Meinke
  • Jürgen Lademann
  • Maxim E Darvin

Russian Science Foundation (19-75-10077)

  • Evgeny A Shirshin

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

Ethics

Human subjects: Positive votes for the experiments have been obtained from the ethics committee of the Charité - Universitätsmedizin Berlin (EA1/078/18, EA4/193/18, EA1/141/12), which were conducted according to the Declaration of Helsinki (59th WMA General Assembly, Seoul, October 2008).

Copyright

© 2022, Kröger 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. Marius Kröger
  2. Jörg Scheffel
  3. Evgeny A Shirshin
  4. Johannes Schleusener
  5. Martina C Meinke
  6. Jürgen Lademann
  7. Marcus Maurer
  8. Maxim E Darvin
(2022)
Label-free imaging of M1 and M2 macrophage phenotypes in the human dermis in vivo using two-photon excited FLIM
eLife 11:e72819.
https://doi.org/10.7554/eLife.72819

Share this article

https://doi.org/10.7554/eLife.72819

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