Dynamic persistence of UPEC intracellular bacterial communities in a human bladder-chip model of urinary tract infection

  1. Kunal Sharma
  2. Neeraj Dhar  Is a corresponding author
  3. Vivek V Thacker  Is a corresponding author
  4. Thomas M Simonet
  5. Francois Signorino-Gelo
  6. Graham William Knott
  7. John D McKinney  Is a corresponding author
  1. Swiss Federal Institute of Technology in Lausanne (EPFL), Switzerland

Abstract

Uropathogenic Escherichia coli (UPEC) proliferate within superficial bladder umbrella cells to form intracellular bacterial communities (IBCs) during early stages of urinary tract infections. However, the dynamic responses of IBCs to host stresses and antibiotic therapy are difficult to assess in situ. We develop a human bladder-chip model wherein umbrella cells and bladder microvascular endothelial cells are co-cultured under flow in urine and nutritive media respectively, and bladder filling and voiding mimicked mechanically by application and release of linear strain. Using time-lapse microscopy, we show that rapid recruitment of neutrophils from the vascular channel to sites of infection leads to swarm and neutrophil extracellular trap formation but does not prevent IBC formation. Subsequently, we tracked bacterial growth dynamics in individual IBCs through two cycles of antibiotic administration interspersed with recovery periods which revealed that the elimination of bacteria within IBCs by the antibiotic was delayed, and in some instances, did not occur at all. During the recovery period, rapid proliferation in a significant fraction of IBCs reseeded new foci of infection through bacterial shedding and host cell exfoliation. These insights reinforce a dynamic role for IBCs as harbours of bacterial persistence, with significant consequences for non-compliance with antibiotic regimens.

Data availability

Data generated in this study has been uploaded to the EPFL community page at Zenodo and is available at the following doi: 10.5281/zenodo.5028262

Article and author information

Author details

  1. Kunal Sharma

    School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL), Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8086-3436
  2. Neeraj Dhar

    School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL), Lausanne, Switzerland
    For correspondence
    neeraj.dhar@epfl.ch
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5887-8137
  3. Vivek V Thacker

    School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL), Lausanne, Switzerland
    For correspondence
    vivekvthacker@gmail.com
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1681-627X
  4. Thomas M Simonet

    School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL), Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  5. Francois Signorino-Gelo

    School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL), Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  6. Graham William Knott

    School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL), Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  7. John D McKinney

    School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL), Lausanne, Switzerland
    For correspondence
    john.mckinney@epfl.ch
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0557-3479

Funding

Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (310030B_176397)

  • John D McKinney

Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (51NF40_180541)

  • John D McKinney

Human Frontier Science Program (Long-Term Fellowship,LT000231/2016-L)

  • Vivek V Thacker

European Molecular Biology Organization (Long-Term Fellowship,921-2015)

  • Vivek V Thacker

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

Ethics

Human subjects: Fresh human blood was procured from anonymised donors via the Transfusion Interregionale CRS network based in Bern, Switzerland. Approval for this project was provided by the same organisation under project number P_257.

Reviewing Editor

  1. Sophie Helaine, Harvard Medical School, United States

Publication history

  1. Received: January 12, 2021
  2. Accepted: July 4, 2021
  3. Accepted Manuscript published: July 5, 2021 (version 1)
  4. Version of Record published: August 10, 2021 (version 2)

Copyright

© 2021, Sharma 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. Kunal Sharma
  2. Neeraj Dhar
  3. Vivek V Thacker
  4. Thomas M Simonet
  5. Francois Signorino-Gelo
  6. Graham William Knott
  7. John D McKinney
(2021)
Dynamic persistence of UPEC intracellular bacterial communities in a human bladder-chip model of urinary tract infection
eLife 10:e66481.
https://doi.org/10.7554/eLife.66481

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