Single-cell analysis of mosquito hemocytes identifies signatures of immune cell sub-types and cell differentiation
- Iowa State university, United States
- Stockholm University, Sweden
- Karolinska Institutet, Sweden
- 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
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.
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).
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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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
Further reading
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