1. Microbiology and Infectious Disease
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Francisella tularensis enters a double membraned compartment following cell-cell transfer

  1. Shaun P Steele  Is a corresponding author
  2. Zach Chamberlain
  3. Jason Park
  4. Thomas H Kawula
  1. Washington State University, United States
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  • Cited 3
  • Views 1,753
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Cite this article as: eLife 2019;8:e45252 doi: 10.7554/eLife.45252

Abstract

Previously, we found that phagocytic cells ingest bacteria directly from the cytosol of infected cells without killing the initially infected cell (Steele et al. 2016). Here, we explored the events immediately following bacterial transfer. Francisella tularensis bacteria acquired from infected cells were found within double-membrane vesicles partially composed from the donor cell plasma membrane. As with phagosomal escape, the F. tularensis Type VI Secretion System (T6SS) was required for vacuole escape. We constructed a T6SS inducible strain and established conditions where this strain is trapped in vacuoles of cells infected through bacterial transfer. Using this strain we identified bacterial transfer events in the lungs of infected mice, demonstrating that this process occurs in infected animals. These data and electron microscopy analysis of the transfer event revealed that macrophages acquire cytoplasm and membrane components of other cells through a process that is distinct from, but related to phagocytosis.

Article and author information

Author details

  1. Shaun P Steele

    School of Global Animal Health, Washington State University, Pullman, United States
    For correspondence
    shaun.steele@wsu.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3760-329X
  2. Zach Chamberlain

    School of Global Animal Health, Washington State University, Pullman, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Jason Park

    School of Global Animal Health, Washington State University, Pullman, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Thomas H Kawula

    School of Global Animal Health, Washington State University, Pullman, United States
    Competing interests
    The authors declare that no competing interests exist.

Funding

National Institute of Allergy and Infectious Diseases (AI082870)

  • Thomas H Kawula

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 animals were handled according to approved institutional animal care and use committee (IACUC) protocol #4946 at Washington State University.

Reviewing Editor

  1. Sophie Helaine, Imperial College London, United Kingdom

Publication history

  1. Received: January 25, 2019
  2. Accepted: April 18, 2019
  3. Accepted Manuscript published: April 24, 2019 (version 1)
  4. Version of Record published: May 3, 2019 (version 2)

Copyright

© 2019, Steele 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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