1. Immunology and Inflammation
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Cytomegalovirus restricts ICOSL expression on antigen presenting cells disabling T cell co-stimulation and contributing to immune evasion

  1. Guillem Angulo
  2. Jelena Zeleznjak
  3. Pablo Martínez-Vicente
  4. Joan Puñet-Ortiz
  5. Hartmut Hengel
  6. Martin Messerle
  7. Annette Oxenius
  8. Stipan Jonjic
  9. Astrid Krmpotic
  10. Pablo Engel
  11. Ana Angulo  Is a corresponding author
  1. University of Barcelona, Spain
  2. University of Rijeka, Croatia
  3. Albert-Ludwigs-Universität Freiburg, Faculty of Medicine, Germany
  4. Hannover Medical School, Germany
  5. ETH Zürich, Switzerland
  6. Faculty of Medicine and Health Sciences, University of Barcelona, Spain
Research Article
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Cite this article as: eLife 2021;10:e59350 doi: 10.7554/eLife.59350

Abstract

Viral infections are controlled, and very often cleared, by activated T lymphocytes. The inducible co-stimulator (ICOS) mediates its functions by binding to its ligand ICOSL, enhancing T-cell activation and optimal germinal center (GC) formation. Here, we show that ICOSL is heavily downmodulated during infection of antigen presenting cells by different herpesviruses. We found that, in murine cytomegalovirus (MCMV), the immunoevasin m138/fcr-1 physically interacts with ICOSL, impeding its maturation and promoting its lysosomal degradation. This viral protein counteracts T-cell responses, in an ICOS-dependent manner, and limits virus control during the acute MCMV infection. Additionally, we report that blockade of ICOSL in MCMV-infected mice critically regulates the production of MCMV-specific antibodies due to a reduction of T follicular helper and GC B cells. Altogether, these findings reveal a novel mechanism evolved by MCMV to counteract adaptive immune surveillance, and demonstrates a role of the ICOS:ICOSL axis in the host defense against herpesviruses.

Data availability

All data generated or analyzed during this study are included in the manuscript and supporting files

Article and author information

Author details

  1. Guillem Angulo

    Biomedical Sciences, Faculty of Medicine, University of Barcelona, Barcelona, Spain
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7086-9754
  2. Jelena Zeleznjak

    Center for Proteomics / Department of Histology and Embryology, University of Rijeka, Rijeka, Croatia
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6619-3675
  3. Pablo Martínez-Vicente

    Biomedical Sciences, School of Medicine, University of Barcelona, Barcelona, Spain
    Competing interests
    No competing interests declared.
  4. Joan Puñet-Ortiz

    Biomedical Sciences, University of Medicine, University of Barcelona, Barcelona, Spain
    Competing interests
    No competing interests declared.
  5. Hartmut Hengel

    Institute of Virology, Albert-Ludwigs-Universität Freiburg, Faculty of Medicine, Freiburg, Germany
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3482-816X
  6. Martin Messerle

    Institute of Virology, Hannover Medical School, Hannover, Germany
    Competing interests
    No competing interests declared.
  7. Annette Oxenius

    Institute of Microbiology, Department of Biology, ETH Zürich, Zürich, Switzerland
    Competing interests
    No competing interests declared.
  8. Stipan Jonjic

    Deparment of Histology and Embryology, University of Rijeka, Rijeka, Croatia
    Competing interests
    Stipan Jonjic, Reviewing editor, eLife.
  9. Astrid Krmpotic

    Department of Histology and Embryology, University of Rijeka, Rijeka, Croatia
    Competing interests
    No competing interests declared.
  10. Pablo Engel

    Immunology Unit, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain
    Competing interests
    No competing interests declared.
  11. Ana Angulo

    Biomedical Sciences, School of Medicine, University of Barcelona, Barcelona, Spain
    For correspondence
    aangulo@ub.edu
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5792-1164

Funding

Ministerio de Economía y Competitividad (SAF 2017-87688)

  • Ana Angulo

Ministerio de Economía y Competitividad (RTI2018-094440-B-I00)

  • Pablo Engel

European Regional Development Fund (KK.01.1.1.01.0006)

  • Stipan Jonjic

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 procedures involving animals and their care were approved (protocol number CEEA 308/12) by the Ethics Committee of the University of Barcelona (Spain) and the Animal Welfare Committee at the University of Rijeka (Croatia) and were conducted in compliance with institutional guidelines as well as with national (Generalitat de Catalunya decree 214/1997, DOGC 2450) and international (Guide for the Care and Use of Laboratory Animals, National Institutes of Health, 85-23, 1985) laws and policies.

Human subjects: Human blood was obtained from healthy volunteer donors through the Blood and Tissue Bank of the Catalan Department of Health (Barcelona, Spain). Utilization of blood products for the experiments conducted was approved by the Ethics Committee of the Hospital Clinic of Barcelona (Barcelona, Spain), and according to the principles of the Declaration of Helsinki.

Reviewing Editor

  1. John W Schoggins, University of Texas Southwestern Medical Center, United States

Publication history

  1. Received: May 27, 2020
  2. Accepted: January 15, 2021
  3. Accepted Manuscript published: January 18, 2021 (version 1)
  4. Version of Record published: January 27, 2021 (version 2)
  5. Version of Record updated: February 25, 2021 (version 3)

Copyright

© 2021, Angulo 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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