Single-cell analysis of mosquito hemocytes identifies signatures of immune cell sub-types and cell differentiation

  1. Hyeogsun Kwon
  2. Mubasher Mohammed
  3. Oscar Franzén
  4. Johan Ankarklev
  5. Ryan Smith  Is a corresponding author
  1. Iowa State university, United States
  2. Stockholm University, Sweden
  3. Karolinska Institutet, Sweden
  4. Iowa State University, United States

Abstract

Mosquito immune cells, known as hemocytes, are integral to cellular and humoral responses that limit pathogen survival and mediate immune priming. However, without reliable cell markers and genetic tools, studies of mosquito immune cells have been limited to morphological observations, leaving several aspects of their biology uncharacterized. Here, we use single-cell RNA sequencing (scRNA-seq) to characterize mosquito immune cells, demonstrating an increased complexity to previously defined prohemocyte, oenocytoid, and granulocyte subtypes. Through functional assays relying on phagocytosis, phagocyte depletion, and RNA-FISH experiments, we define markers to accurately distinguish immune cell subtypes and provide evidence for immune cell maturation and differentiation. In addition, gene-silencing experiments demonstrate the importance of lozenge in defining the mosquito oenocytoid cell fate. Together, our scRNA-seq analysis provides an important foundation for future studies of mosquito immune cell biology and a valuable resource for comparative invertebrate immunology.

Data availability

Data generated and analysed in this study are included in the manuscript and supporting files. In addition, data can be visualized and downloaded using the following server: https://alona.panglaodb.se/results.html?job=2c2r1NM5Zl2qcW44RSrjkHf3Oyv51y_5f09d74b770c9N/A

Article and author information

Author details

  1. Hyeogsun Kwon

    Entomology, Iowa State university, Ames, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4141-4061
  2. Mubasher Mohammed

    Molecular Biosciences, Stockholm University, Stockholm, Sweden
    Competing interests
    The authors declare that no competing interests exist.
  3. Oscar Franzén

    Integrated Cardio Metabolic Centre, Department of Medicine, Karolinska Institutet, Huddinge, Sweden
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7573-0812
  4. Johan Ankarklev

    Molecular Biosciences, Stockholm University, Stockholm, Sweden
    Competing interests
    The authors declare that no competing interests exist.
  5. Ryan Smith

    Entomology, Iowa State University, Ames, United States
    For correspondence
    smithr@iastate.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0245-2265

Funding

Swedish Society for Medical Research

  • Johan Ankarklev

Swedish Research Council

  • Johan Ankarklev

National Institute of Allergy and Infectious Diseases (R21AI144705)

  • Ryan Smith

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

Reviewing Editor

  1. Bruno Lemaître, École Polytechnique Fédérale de Lausanne, Switzerland

Ethics

Animal experimentation: The protocols and procedures used in this study were approved by the Animal Care and Use Committee at Iowa State University (IACUC-18-228).

Version history

  1. Received: January 2, 2021
  2. Accepted: July 27, 2021
  3. Accepted Manuscript published: July 28, 2021 (version 1)
  4. Version of Record published: August 19, 2021 (version 2)
  5. Version of Record updated: November 28, 2022 (version 3)

Copyright

© 2021, Kwon 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. Hyeogsun Kwon
  2. Mubasher Mohammed
  3. Oscar Franzén
  4. Johan Ankarklev
  5. Ryan Smith
(2021)
Single-cell analysis of mosquito hemocytes identifies signatures of immune cell sub-types and cell differentiation
eLife 10:e66192.
https://doi.org/10.7554/eLife.66192

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https://doi.org/10.7554/eLife.66192

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