A role for phagocytosis in inducing cell death during thymocyte negative selection

  1. Nadia S Kurd
  2. Lydia K Lutes
  3. Jaewon Yoon
  4. Shiao Wei Chan
  5. Ivan L Dzhagalov
  6. Ashley R Hoover
  7. Ellen A Robey  Is a corresponding author
  1. University of California, Berkeley, United States

Abstract

Autoreactive thymocytes are eliminated during negative selection in the thymus, a process important for establishing self-tolerance. Thymic phagocytes serve to remove dead thymocytes, but whether they play additional roles during negative selection remains unclear. Here, using a murine thymic slice model in which thymocytes undergo negative selection in situ, we demonstrate that phagocytosis promotes negative selection, and provide evidence for the escape of autoreactive CD8 T cells to the periphery when phagocytosis in the thymus is impaired. We also show that negative selection is more efficient when the phagocyte also presents the negative selecting peptide. Our findings support a model for negative selection in which the death process initiated following strong TCR signaling is facilitated by phagocytosis. Thus, the phagocytic capability of cells that present self-peptides is a key determinant of thymocyte fate.

Data availability

Data that support the findings of this study are reported in figures accompanying the main text and supplementary figures.

Article and author information

Author details

  1. Nadia S Kurd

    Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Lydia K Lutes

    Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Jaewon Yoon

    Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Shiao Wei Chan

    Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Ivan L Dzhagalov

    Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Ashley R Hoover

    Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Ellen A Robey

    Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    For correspondence
    erobey@berkeley.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3630-5266

Funding

National Institutes of Health (R01AI064227)

  • Ellen A Robey

University of California (Cancer Research Coordinating Committee)

  • Nadia S Kurd

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

Ethics

Animal experimentation: All mice were bred and maintained under pathogen-free conditions in an American Association of Laboratory Animal Care-approved facility at the University of California, Berkeley. All procedures were approved by the University of California, Berkeley Animal Use and Care Committee under Animal Use Protocol #AUP-2016-07-9006-1.

Reviewing Editor

  1. Shimon Sakaguchi, Osaka University, Japan

Publication history

  1. Received: May 1, 2019
  2. Accepted: December 21, 2019
  3. Accepted Manuscript published: December 23, 2019 (version 1)
  4. Version of Record published: January 13, 2020 (version 2)
  5. Version of Record updated: February 14, 2020 (version 3)

Copyright

© 2019, Kurd 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. Nadia S Kurd
  2. Lydia K Lutes
  3. Jaewon Yoon
  4. Shiao Wei Chan
  5. Ivan L Dzhagalov
  6. Ashley R Hoover
  7. Ellen A Robey
(2019)
A role for phagocytosis in inducing cell death during thymocyte negative selection
eLife 8:e48097.
https://doi.org/10.7554/eLife.48097

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