Abstract

P2X7 receptor activation induces the release of different cellular proteins, such as CD14, a glycosylphosphatidylinositol (GPI)-anchored protein to the plasma membrane important for LPS signaling via TLR4. Circulating CD14 has been found at elevated levels in sepsis, but the exact mechanism of CD14 release in sepsis has not been established. Here we show for first time that P2X7 receptor induces the release of CD14 in extracellular vesicles, resulting in a net reduction in macrophage plasma membrane CD14 that functionally affects LPS, but not monophosphoryl lipid A, pro-inflammatory cytokine production. Also, we found that during a murine model of sepsis, P2X7 receptor activity is important for maintaining elevated levels of CD14 in biological fluids and a decrease in its activity results in higher bacterial load and exacerbated organ damage, ultimately leading to premature deaths. Our data reveal that P2X7 is a key receptor for helping to clear sepsis because it maintains elevated concentrations of circulating CD14 during infection.

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All data generated or analysed during this study are included in the manuscript and provided as raw data as single values for all Figures.

Article and author information

Author details

  1. Cristina Alarcón-Vila

    Molecular Inflammation and Experimental Surgery, Biomedical Research Institute of Murcia IMIB-Arrixaca, Murcia, Spain
    Competing interests
    The authors declare that no competing interests exist.
  2. Alberto Baroja-Mazo

    Molecular Inflammation and Experimental Surgery, Biomedical Research Institute of Murcia IMIB-Arrixaca, Murcia, Spain
    Competing interests
    The authors declare that no competing interests exist.
  3. Carlos de Torre-Minguela

    Molecular Inflammation and Experimental Surgery, Biomedical Research Institute of Murcia IMIB-Arrixaca, Murcia, Spain
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3314-3203
  4. Carlos M Martínez

    Pathology Platform, Biomedical Research Institute of Murcia IMIB-Arrixaca, Murcia, Spain
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3307-1326
  5. Juan J Martínez-García

    Molecular Inflammation and Experimental Surgery, Biomedical Research Institute of Murcia IMIB-Arrixaca, Murcia, Spain
    Competing interests
    The authors declare that no competing interests exist.
  6. Helios Martínez-Banaclocha

    Molecular Inflammation and Experimental Surgery, Biomedical Research Institute of Murcia IMIB-Arrixaca, Murcia, Spain
    Competing interests
    The authors declare that no competing interests exist.
  7. Carlos García-Palenciano

    Molecular Inflammation and Experimental Surgery, Biomedical Research Institute of Murcia IMIB-Arrixaca, Murcia, Spain
    Competing interests
    The authors declare that no competing interests exist.
  8. Pablo Pelegrin

    Molecular Inflammation and Experimental Surgery, Biomedical Research Institute of Murcia IMIB-Arrixaca, Murcia, Spain
    For correspondence
    pablo.pelegrin@imib.es
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9688-1804

Funding

European research council (614578)

  • Pablo Pelegrin

European Research council (899636)

  • Carlos García-Palenciano
  • Pablo Pelegrin

Ministerio de Economía y Competitividad (SAF2017-88276-R)

  • Pablo Pelegrin

Fundacion Seneca (20859/PI/18)

  • Carlos García-Palenciano
  • Pablo Pelegrin

Fundacion Seneca (21081/PDC/19)

  • Pablo Pelegrin

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 experimental protocols for animal handling were refined and approved by the Animal Health Service of the General Directorate of Fishing and Farming of the Council of Murcia (Servicio de Sanidad Animal, Dirección General de Ganadería y Pesca, Consejería de Agricultura y Agua Región de Murcia, permit reference A1320140201). Mice were used in accordance with the Hospital Clínico Universitario Virgen Arrixaca animal experimentation guidelines (Permit Number 221116/1/PE), and Spanish national (Royal Decree 1201/2005 and Law 32/2007) and EU (86/609/EEC and 335 2010/63/EU) legislation. All surgery was performed under sodium pentobarbital anesthesia, and every effort was made to minimize suffering.

Human subjects: The samples and data from patients included in this study were provided by the Biobanco en Red de la Región de Murcia (PT13/0010/0018), which is integrated into the Spanish National Biobanks Network (B.000859) and approved by the clinical ethics committee of the Clinical University Hospital Virgen de la Arrixaca (reference numbers PI13/00174, 2019-9-4-HCUVA, 2019-12-15-HCUVA and 2019-12-471 14-HCUVA). All study procedures were conducted in accordance with the declaration of Helsinki. Whole peripheral blood samples were collected after receiving written informed consent from intraabdominal sepsis patients at the Surgical Critical Unit from the Clinical University Hospital Virgen de la Arrixaca.

Reviewing Editor

  1. Evangelos J Giamarellos-Bourboulis, Attikon University Hospital, Greece

Version history

  1. Received: July 8, 2020
  2. Accepted: October 31, 2020
  3. Accepted Manuscript published: November 2, 2020 (version 1)
  4. Version of Record published: November 26, 2020 (version 2)

Copyright

© 2020, Alarcón-Vila 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. Cristina Alarcón-Vila
  2. Alberto Baroja-Mazo
  3. Carlos de Torre-Minguela
  4. Carlos M Martínez
  5. Juan J Martínez-García
  6. Helios Martínez-Banaclocha
  7. Carlos García-Palenciano
  8. Pablo Pelegrin
(2020)
CD14 release induced by P2X7 receptor restrict inflammation and increases survival during sepsis
eLife 9:e60849.
https://doi.org/10.7554/eLife.60849

Share this article

https://doi.org/10.7554/eLife.60849

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