Abstract

Drosophila blood cells, called hemocytes, are classified into plasmatocytes, crystal cells, and lamellocytes based on the expression of a few marker genes and cell morphologies, which are inadequate to classify the complete hemocyte repertoire. Here, we used single-cell RNA sequencing (scRNA-seq) to map hemocytes across different inflammatory conditions in larvae. We resolved plasmatocytes into different states based on the expression of genes involved in cell cycle, antimicrobial response, and metabolism together with the identification of intermediate states. Further, we discovered rare subsets within crystal cells and lamellocytes that express fibroblast growth factor (FGF) ligand branchless and receptor breathless, respectively. We demonstrate that these FGF components are required for mediating effective immune responses against parasitoid wasp eggs, highlighting a novel role for FGF signaling in inter-hemocyte crosstalk. Our scRNA-seq analysis reveals the diversity of hemocytes and provides a rich resource of gene expression profiles for a systems-level understanding of their functions.

Data availability

Sequencing data have been deposited in GEO under the accession number GSE146596Elsewhere, data can be visualized at: www.flyrnai.org/scRNA/blood/Data code can accessed at: https://github.com/hbc/A-single-cell-survey-of-Drosophila-blood

The following data sets were generated
The following previously published data sets were used

Article and author information

Author details

  1. Sudhir Gopal Tattikota

    Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, United States
    For correspondence
    sudhir_gt@hms.harvard.edu
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0318-5533
  2. Bumsik Cho

    Department of Life Science, Hanyang University, Seoul, Republic of Korea
    Competing interests
    No competing interests declared.
  3. Yifang Liu

    Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, United States
    Competing interests
    No competing interests declared.
  4. Yanhui Hu

    Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, United States
    Competing interests
    No competing interests declared.
  5. Victor Barrera

    Biostatistics, Harvard T H Chan Bioinformatics Core, Boston, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0590-4634
  6. Michael J Steinbaugh

    Biostatistics, Harvard T H Chan Bioinformatics Core, Boston, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2403-2221
  7. Sang-Ho Yoon

    Department of Life Science, Hanyang University, Seoul, Republic of Korea
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2611-5554
  8. Aram Comjean

    Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, United States
    Competing interests
    No competing interests declared.
  9. Fangge Li

    Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, United States
    Competing interests
    No competing interests declared.
  10. Franz Dervis

    Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, United States
    Competing interests
    No competing interests declared.
  11. Ruei-Jiun Hung

    Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, United States
    Competing interests
    No competing interests declared.
  12. Jin-Wu Nam

    Department of Life Science, Hanyang University, Seoul, Republic of Korea
    Competing interests
    No competing interests declared.
  13. Shannan Ho Sui

    Biostatistics, Harvard T H Chan Bioinformatics Core, Boston, United States
    Competing interests
    No competing interests declared.
  14. Jiwon Shim

    Department of Life Science, Hanyang University, Seoul, Republic of Korea
    Competing interests
    Jiwon Shim, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2409-1130
  15. Norbert Perrimon

    Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, United States
    For correspondence
    perrimon@receptor.med.harvard.edu
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7542-472X

Funding

Samsung Science and Technology Foundation (SSTF-BA1701-15)

  • Jiwon Shim

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

Copyright

© 2020, Tattikota 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. Sudhir Gopal Tattikota
  2. Bumsik Cho
  3. Yifang Liu
  4. Yanhui Hu
  5. Victor Barrera
  6. Michael J Steinbaugh
  7. Sang-Ho Yoon
  8. Aram Comjean
  9. Fangge Li
  10. Franz Dervis
  11. Ruei-Jiun Hung
  12. Jin-Wu Nam
  13. Shannan Ho Sui
  14. Jiwon Shim
  15. Norbert Perrimon
(2020)
A single-cell survey of Drosophila blood
eLife 9:e54818.
https://doi.org/10.7554/eLife.54818

Share this article

https://doi.org/10.7554/eLife.54818

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