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Increased Virulence of an Epidemic Strain of Mycobacterium massiliense in Mice
BACKGROUND: Chronic pulmonary disease and skin/soft tissue infections due to non-tuberculous mycobacteria (NTM) of the Mycobacterium chelonae-abscessus-massiliense group is an emerging health problem worldwide. Moreover, the cure rate for the infections this group causes is low despite aggressive tr...
Autores principales: | , , , , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Public Library of Science
2011
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3171484/ https://www.ncbi.nlm.nih.gov/pubmed/21931831 http://dx.doi.org/10.1371/journal.pone.0024726 |
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author | Shang, Shaobin Gibbs, Sara Henao-Tamayo, Marcela Shanley, Crystal A. McDonnell, Gerald Duarte, Rafael Silva Ordway, Diane J. Jackson, Mary |
author_facet | Shang, Shaobin Gibbs, Sara Henao-Tamayo, Marcela Shanley, Crystal A. McDonnell, Gerald Duarte, Rafael Silva Ordway, Diane J. Jackson, Mary |
author_sort | Shang, Shaobin |
collection | PubMed |
description | BACKGROUND: Chronic pulmonary disease and skin/soft tissue infections due to non-tuberculous mycobacteria (NTM) of the Mycobacterium chelonae-abscessus-massiliense group is an emerging health problem worldwide. Moreover, the cure rate for the infections this group causes is low despite aggressive treatment. Post-surgical outbreaks that reached epidemic proportions in Brazil recently were caused by M. massiliense isolates resistant to high-level disinfection with glutaraldehyde (GTA). Understanding the differences in the virulence and host immune responses induced by NTM differing in their sensitivity to disinfectants, and therefore their relative threat of causing outbreaks in hospitals, is an important issue. METHODOLOGY/PRINCIPAL FINDING: We compared the replication and survival inside macrophages of a GTA-susceptible reference Mycobacterium massiliense clinical isolate CIP 108297 and an epidemic strain from Brazil, CRM-0019, and characterized the immune responses of IFNγ knockout mice exposed to a high dose aerosol with these two isolates. CRM-0019 replicated more efficiently than CIP 108297 inside mouse bone marrow macrophages. Moreover, the animals infected with CRM-0019 showed a progressive lung infection characterized by a delayed influx of CD4+ and CD8+ T cells, culminating in extensive lung consolidation and demonstrated increased numbers of pulmonary CD4+ Foxp3+ regulatory T cells compared to those infected with the reference strain. Immunosuppressive activity of regulatory T cells may contribute to the progression and worsening of NTM disease by preventing the induction of specific protective immune responses. CONCLUSIONS/SIGNIFICANCE: These results provide the first direct evidence of the increased virulence in macrophages and mice and pathogenicity in vivo of the Brazilian epidemic isolate and the first observation that NTM infections can be associated with variable levels of regulatory T cells which may impact on their virulence and ability to persist in the host. |
format | Online Article Text |
id | pubmed-3171484 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2011 |
publisher | Public Library of Science |
record_format | MEDLINE/PubMed |
spelling | pubmed-31714842011-09-19 Increased Virulence of an Epidemic Strain of Mycobacterium massiliense in Mice Shang, Shaobin Gibbs, Sara Henao-Tamayo, Marcela Shanley, Crystal A. McDonnell, Gerald Duarte, Rafael Silva Ordway, Diane J. Jackson, Mary PLoS One Research Article BACKGROUND: Chronic pulmonary disease and skin/soft tissue infections due to non-tuberculous mycobacteria (NTM) of the Mycobacterium chelonae-abscessus-massiliense group is an emerging health problem worldwide. Moreover, the cure rate for the infections this group causes is low despite aggressive treatment. Post-surgical outbreaks that reached epidemic proportions in Brazil recently were caused by M. massiliense isolates resistant to high-level disinfection with glutaraldehyde (GTA). Understanding the differences in the virulence and host immune responses induced by NTM differing in their sensitivity to disinfectants, and therefore their relative threat of causing outbreaks in hospitals, is an important issue. METHODOLOGY/PRINCIPAL FINDING: We compared the replication and survival inside macrophages of a GTA-susceptible reference Mycobacterium massiliense clinical isolate CIP 108297 and an epidemic strain from Brazil, CRM-0019, and characterized the immune responses of IFNγ knockout mice exposed to a high dose aerosol with these two isolates. CRM-0019 replicated more efficiently than CIP 108297 inside mouse bone marrow macrophages. Moreover, the animals infected with CRM-0019 showed a progressive lung infection characterized by a delayed influx of CD4+ and CD8+ T cells, culminating in extensive lung consolidation and demonstrated increased numbers of pulmonary CD4+ Foxp3+ regulatory T cells compared to those infected with the reference strain. Immunosuppressive activity of regulatory T cells may contribute to the progression and worsening of NTM disease by preventing the induction of specific protective immune responses. CONCLUSIONS/SIGNIFICANCE: These results provide the first direct evidence of the increased virulence in macrophages and mice and pathogenicity in vivo of the Brazilian epidemic isolate and the first observation that NTM infections can be associated with variable levels of regulatory T cells which may impact on their virulence and ability to persist in the host. Public Library of Science 2011-09-12 /pmc/articles/PMC3171484/ /pubmed/21931831 http://dx.doi.org/10.1371/journal.pone.0024726 Text en Shang 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 Shang, Shaobin Gibbs, Sara Henao-Tamayo, Marcela Shanley, Crystal A. McDonnell, Gerald Duarte, Rafael Silva Ordway, Diane J. Jackson, Mary Increased Virulence of an Epidemic Strain of Mycobacterium massiliense in Mice |
title | Increased Virulence of an Epidemic Strain of Mycobacterium massiliense in Mice |
title_full | Increased Virulence of an Epidemic Strain of Mycobacterium massiliense in Mice |
title_fullStr | Increased Virulence of an Epidemic Strain of Mycobacterium massiliense in Mice |
title_full_unstemmed | Increased Virulence of an Epidemic Strain of Mycobacterium massiliense in Mice |
title_short | Increased Virulence of an Epidemic Strain of Mycobacterium massiliense in Mice |
title_sort | increased virulence of an epidemic strain of mycobacterium massiliense in mice |
topic | Research Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3171484/ https://www.ncbi.nlm.nih.gov/pubmed/21931831 http://dx.doi.org/10.1371/journal.pone.0024726 |
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