Clonal expansion during Staphylococcus aureus infection dynamics reveals the effect of antibiotic intervention.

To slow the inexorable rise of antibiotic resistance we must understand how drugs impact on pathogenesis and influence the selection of resistant clones. Staphylococcus aureus is an important human pathogen with populations of antibiotic-resistant bacteria in hospitals and the community. Host phagoc...

Full description

Saved in:
Bibliographic Details
Main Authors: Gareth McVicker, Tomasz K Prajsnar, Alexander Williams, Nelly L Wagner, Michael Boots, Stephen A Renshaw, Simon J Foster
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2014-02-01
Series:PLoS Pathogens
Online Access:https://journals.plos.org/plospathogens/article/file?id=10.1371/journal.ppat.1003959&type=printable
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849726673076879360
author Gareth McVicker
Tomasz K Prajsnar
Alexander Williams
Nelly L Wagner
Michael Boots
Stephen A Renshaw
Simon J Foster
author_facet Gareth McVicker
Tomasz K Prajsnar
Alexander Williams
Nelly L Wagner
Michael Boots
Stephen A Renshaw
Simon J Foster
author_sort Gareth McVicker
collection DOAJ
description To slow the inexorable rise of antibiotic resistance we must understand how drugs impact on pathogenesis and influence the selection of resistant clones. Staphylococcus aureus is an important human pathogen with populations of antibiotic-resistant bacteria in hospitals and the community. Host phagocytes play a crucial role in controlling S. aureus infection, which can lead to a population "bottleneck" whereby clonal expansion of a small fraction of the initial inoculum founds a systemic infection. Such population dynamics may have important consequences on the effect of antibiotic intervention. Low doses of antibiotics have been shown to affect in vitro growth and the generation of resistant mutants over the long term, however whether this has any in vivo relevance is unknown. In this work, the population dynamics of S. aureus pathogenesis were studied in vivo using antibiotic-resistant strains constructed in an isogenic background, coupled with systemic models of infection in both the mouse and zebrafish embryo. Murine experiments revealed unexpected and complex bacterial population kinetics arising from clonal expansion during infection in particular organs. We subsequently elucidated the effect of antibiotic intervention within the host using mixed inocula of resistant and sensitive bacteria. Sub-curative tetracycline doses support the preferential expansion of resistant microorganisms, importantly unrelated to effects on growth rate or de novo resistance acquisition. This novel phenomenon is generic, occurring with methicillin-resistant S. aureus (MRSA) in the presence of β-lactams and with the unrelated human pathogen Pseudomonas aeruginosa. The selection of resistant clones at low antibiotic levels can result in a rapid increase in their prevalence under conditions that would previously not be thought to favor them. Our results have key implications for the design of effective treatment regimes to limit the spread of antimicrobial resistance, where inappropriate usage leading to resistance may reduce the efficacy of life-saving drugs.
format Article
id doaj-art-2ea585a4bab64a819d37ea30f9cdbf15
institution DOAJ
issn 1553-7366
1553-7374
language English
publishDate 2014-02-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS Pathogens
spelling doaj-art-2ea585a4bab64a819d37ea30f9cdbf152025-08-20T03:10:07ZengPublic Library of Science (PLoS)PLoS Pathogens1553-73661553-73742014-02-01102e100395910.1371/journal.ppat.1003959Clonal expansion during Staphylococcus aureus infection dynamics reveals the effect of antibiotic intervention.Gareth McVickerTomasz K PrajsnarAlexander WilliamsNelly L WagnerMichael BootsStephen A RenshawSimon J FosterTo slow the inexorable rise of antibiotic resistance we must understand how drugs impact on pathogenesis and influence the selection of resistant clones. Staphylococcus aureus is an important human pathogen with populations of antibiotic-resistant bacteria in hospitals and the community. Host phagocytes play a crucial role in controlling S. aureus infection, which can lead to a population "bottleneck" whereby clonal expansion of a small fraction of the initial inoculum founds a systemic infection. Such population dynamics may have important consequences on the effect of antibiotic intervention. Low doses of antibiotics have been shown to affect in vitro growth and the generation of resistant mutants over the long term, however whether this has any in vivo relevance is unknown. In this work, the population dynamics of S. aureus pathogenesis were studied in vivo using antibiotic-resistant strains constructed in an isogenic background, coupled with systemic models of infection in both the mouse and zebrafish embryo. Murine experiments revealed unexpected and complex bacterial population kinetics arising from clonal expansion during infection in particular organs. We subsequently elucidated the effect of antibiotic intervention within the host using mixed inocula of resistant and sensitive bacteria. Sub-curative tetracycline doses support the preferential expansion of resistant microorganisms, importantly unrelated to effects on growth rate or de novo resistance acquisition. This novel phenomenon is generic, occurring with methicillin-resistant S. aureus (MRSA) in the presence of β-lactams and with the unrelated human pathogen Pseudomonas aeruginosa. The selection of resistant clones at low antibiotic levels can result in a rapid increase in their prevalence under conditions that would previously not be thought to favor them. Our results have key implications for the design of effective treatment regimes to limit the spread of antimicrobial resistance, where inappropriate usage leading to resistance may reduce the efficacy of life-saving drugs.https://journals.plos.org/plospathogens/article/file?id=10.1371/journal.ppat.1003959&type=printable
spellingShingle Gareth McVicker
Tomasz K Prajsnar
Alexander Williams
Nelly L Wagner
Michael Boots
Stephen A Renshaw
Simon J Foster
Clonal expansion during Staphylococcus aureus infection dynamics reveals the effect of antibiotic intervention.
PLoS Pathogens
title Clonal expansion during Staphylococcus aureus infection dynamics reveals the effect of antibiotic intervention.
title_full Clonal expansion during Staphylococcus aureus infection dynamics reveals the effect of antibiotic intervention.
title_fullStr Clonal expansion during Staphylococcus aureus infection dynamics reveals the effect of antibiotic intervention.
title_full_unstemmed Clonal expansion during Staphylococcus aureus infection dynamics reveals the effect of antibiotic intervention.
title_short Clonal expansion during Staphylococcus aureus infection dynamics reveals the effect of antibiotic intervention.
title_sort clonal expansion during staphylococcus aureus infection dynamics reveals the effect of antibiotic intervention
url https://journals.plos.org/plospathogens/article/file?id=10.1371/journal.ppat.1003959&type=printable
work_keys_str_mv AT garethmcvicker clonalexpansionduringstaphylococcusaureusinfectiondynamicsrevealstheeffectofantibioticintervention
AT tomaszkprajsnar clonalexpansionduringstaphylococcusaureusinfectiondynamicsrevealstheeffectofantibioticintervention
AT alexanderwilliams clonalexpansionduringstaphylococcusaureusinfectiondynamicsrevealstheeffectofantibioticintervention
AT nellylwagner clonalexpansionduringstaphylococcusaureusinfectiondynamicsrevealstheeffectofantibioticintervention
AT michaelboots clonalexpansionduringstaphylococcusaureusinfectiondynamicsrevealstheeffectofantibioticintervention
AT stephenarenshaw clonalexpansionduringstaphylococcusaureusinfectiondynamicsrevealstheeffectofantibioticintervention
AT simonjfoster clonalexpansionduringstaphylococcusaureusinfectiondynamicsrevealstheeffectofantibioticintervention