Cargando…

Live Imaging of Bioluminescent Leptospira interrogans in Mice Reveals Renal Colonization as a Stealth Escape from the Blood Defenses and Antibiotics

Leptospira (L.) interrogans are bacteria responsible for a worldwide reemerging zoonosis. Some animals asymptomatically carry L. interrogans in their kidneys and excrete bacteria in their urine, which contaminates the environment. Humans are infected through skin contact with leptospires and develop...

Descripción completa

Detalles Bibliográficos
Autores principales: Ratet, Gwenn, Veyrier, Frédéric J., Fanton d'Andon, Martine, Kammerscheit, Xavier, Nicola, Marie-Anne, Picardeau, Mathieu, Boneca, Ivo G., Werts, Catherine
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Public Library of Science 2014
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4256284/
https://www.ncbi.nlm.nih.gov/pubmed/25474719
http://dx.doi.org/10.1371/journal.pntd.0003359
_version_ 1782347561867149312
author Ratet, Gwenn
Veyrier, Frédéric J.
Fanton d'Andon, Martine
Kammerscheit, Xavier
Nicola, Marie-Anne
Picardeau, Mathieu
Boneca, Ivo G.
Werts, Catherine
author_facet Ratet, Gwenn
Veyrier, Frédéric J.
Fanton d'Andon, Martine
Kammerscheit, Xavier
Nicola, Marie-Anne
Picardeau, Mathieu
Boneca, Ivo G.
Werts, Catherine
author_sort Ratet, Gwenn
collection PubMed
description Leptospira (L.) interrogans are bacteria responsible for a worldwide reemerging zoonosis. Some animals asymptomatically carry L. interrogans in their kidneys and excrete bacteria in their urine, which contaminates the environment. Humans are infected through skin contact with leptospires and develop mild to severe leptospirosis. Previous attempts to construct fluorescent or bioluminescent leptospires, which would permit in vivo visualization and investigation of host defense mechanisms during infection, have been unsuccessful. Using a firefly luciferase cassette and random transposition tools, we constructed bioluminescent chromosomal transformants in saprophytic and pathogenic leptospires. The kinetics of leptospiral dissemination in mice, after intraperitoneal inoculation with a pathogenic transformant, was tracked by bioluminescence using live imaging. For infective doses of 10(6) to 10(7) bacteria, we observed dissemination and exponential growth of leptospires in the blood, followed by apparent clearance of bacteria. However, with 2×10(8) bacteria, the septicemia led to the death of mice within 3 days post-infection. In surviving mice, one week after infection, pathogenic leptospires reemerged only in the kidneys, where they multiplied and reached a steady state, leading to a sustained chronic renal infection. These experiments reveal that a fraction of the leptospiral population escapes the potent blood defense, and colonizes a defined number of niches in the kidneys, proportional to the infective dose. Antibiotic treatments failed to eradicate leptospires that colonized the kidneys, although they were effective against L. interrogans if administered before or early after infection. To conclude, mice infected with bioluminescent L. interrogans proved to be a novel model to study both acute and chronic leptospirosis, and revealed that, in the kidneys, leptospires are protected from antibiotics. These bioluminescent leptospires represent a powerful new tool to challenge mice treated with drugs or vaccines, and test the survival, dissemination, and transmission of leptospires between environment and hosts.
format Online
Article
Text
id pubmed-4256284
institution National Center for Biotechnology Information
language English
publishDate 2014
publisher Public Library of Science
record_format MEDLINE/PubMed
spelling pubmed-42562842014-12-11 Live Imaging of Bioluminescent Leptospira interrogans in Mice Reveals Renal Colonization as a Stealth Escape from the Blood Defenses and Antibiotics Ratet, Gwenn Veyrier, Frédéric J. Fanton d'Andon, Martine Kammerscheit, Xavier Nicola, Marie-Anne Picardeau, Mathieu Boneca, Ivo G. Werts, Catherine PLoS Negl Trop Dis Research Article Leptospira (L.) interrogans are bacteria responsible for a worldwide reemerging zoonosis. Some animals asymptomatically carry L. interrogans in their kidneys and excrete bacteria in their urine, which contaminates the environment. Humans are infected through skin contact with leptospires and develop mild to severe leptospirosis. Previous attempts to construct fluorescent or bioluminescent leptospires, which would permit in vivo visualization and investigation of host defense mechanisms during infection, have been unsuccessful. Using a firefly luciferase cassette and random transposition tools, we constructed bioluminescent chromosomal transformants in saprophytic and pathogenic leptospires. The kinetics of leptospiral dissemination in mice, after intraperitoneal inoculation with a pathogenic transformant, was tracked by bioluminescence using live imaging. For infective doses of 10(6) to 10(7) bacteria, we observed dissemination and exponential growth of leptospires in the blood, followed by apparent clearance of bacteria. However, with 2×10(8) bacteria, the septicemia led to the death of mice within 3 days post-infection. In surviving mice, one week after infection, pathogenic leptospires reemerged only in the kidneys, where they multiplied and reached a steady state, leading to a sustained chronic renal infection. These experiments reveal that a fraction of the leptospiral population escapes the potent blood defense, and colonizes a defined number of niches in the kidneys, proportional to the infective dose. Antibiotic treatments failed to eradicate leptospires that colonized the kidneys, although they were effective against L. interrogans if administered before or early after infection. To conclude, mice infected with bioluminescent L. interrogans proved to be a novel model to study both acute and chronic leptospirosis, and revealed that, in the kidneys, leptospires are protected from antibiotics. These bioluminescent leptospires represent a powerful new tool to challenge mice treated with drugs or vaccines, and test the survival, dissemination, and transmission of leptospires between environment and hosts. Public Library of Science 2014-12-04 /pmc/articles/PMC4256284/ /pubmed/25474719 http://dx.doi.org/10.1371/journal.pntd.0003359 Text en © 2014 Ratet et al http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited.
spellingShingle Research Article
Ratet, Gwenn
Veyrier, Frédéric J.
Fanton d'Andon, Martine
Kammerscheit, Xavier
Nicola, Marie-Anne
Picardeau, Mathieu
Boneca, Ivo G.
Werts, Catherine
Live Imaging of Bioluminescent Leptospira interrogans in Mice Reveals Renal Colonization as a Stealth Escape from the Blood Defenses and Antibiotics
title Live Imaging of Bioluminescent Leptospira interrogans in Mice Reveals Renal Colonization as a Stealth Escape from the Blood Defenses and Antibiotics
title_full Live Imaging of Bioluminescent Leptospira interrogans in Mice Reveals Renal Colonization as a Stealth Escape from the Blood Defenses and Antibiotics
title_fullStr Live Imaging of Bioluminescent Leptospira interrogans in Mice Reveals Renal Colonization as a Stealth Escape from the Blood Defenses and Antibiotics
title_full_unstemmed Live Imaging of Bioluminescent Leptospira interrogans in Mice Reveals Renal Colonization as a Stealth Escape from the Blood Defenses and Antibiotics
title_short Live Imaging of Bioluminescent Leptospira interrogans in Mice Reveals Renal Colonization as a Stealth Escape from the Blood Defenses and Antibiotics
title_sort live imaging of bioluminescent leptospira interrogans in mice reveals renal colonization as a stealth escape from the blood defenses and antibiotics
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4256284/
https://www.ncbi.nlm.nih.gov/pubmed/25474719
http://dx.doi.org/10.1371/journal.pntd.0003359
work_keys_str_mv AT ratetgwenn liveimagingofbioluminescentleptospirainterrogansinmicerevealsrenalcolonizationasastealthescapefromtheblooddefensesandantibiotics
AT veyrierfredericj liveimagingofbioluminescentleptospirainterrogansinmicerevealsrenalcolonizationasastealthescapefromtheblooddefensesandantibiotics
AT fantondandonmartine liveimagingofbioluminescentleptospirainterrogansinmicerevealsrenalcolonizationasastealthescapefromtheblooddefensesandantibiotics
AT kammerscheitxavier liveimagingofbioluminescentleptospirainterrogansinmicerevealsrenalcolonizationasastealthescapefromtheblooddefensesandantibiotics
AT nicolamarieanne liveimagingofbioluminescentleptospirainterrogansinmicerevealsrenalcolonizationasastealthescapefromtheblooddefensesandantibiotics
AT picardeaumathieu liveimagingofbioluminescentleptospirainterrogansinmicerevealsrenalcolonizationasastealthescapefromtheblooddefensesandantibiotics
AT bonecaivog liveimagingofbioluminescentleptospirainterrogansinmicerevealsrenalcolonizationasastealthescapefromtheblooddefensesandantibiotics
AT wertscatherine liveimagingofbioluminescentleptospirainterrogansinmicerevealsrenalcolonizationasastealthescapefromtheblooddefensesandantibiotics