The bacterial microbiota in inflammatory lung diseases
Gary B Huffnagle1, Robert P Dickson2
1Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA; Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, USA.
Clinical Immunology (Orlando, Fla.)
|July 1, 2015
Summary
The lungs harbor bacteria even in health, challenging the sterile lung theory. Chronic lung diseases alter lung microbiome dynamics, potentially leading to pathogen blooms and new colonizers.
Area of Science:
- Microbiology
- Pulmonology
- Ecosystem dynamics
Background:
- Historical evidence suggests lungs are not sterile.
- The respiratory tract functions as a unified ecosystem.
- Bacterial colonization in healthy lungs is transient.
Purpose of the Study:
- To review evidence on lung microbiome in health and disease.
- To discuss the impact of chronic lung disease on lung microbiota.
- To highlight emerging bacterial colonizers.
Main Methods:
- Literature review of studies from the 1920s to present.
- Analysis of host-microbe interactions in the respiratory tract.
- Discussion of culture-independent identification methods.
Main Results:
- Lungs are consistently colonized by bacteria in health.
- Chronic lung diseases alter lung bacterial dynamics.
- New bacterial species like Pseudomonas fluorescens are identified.
Conclusions:
- The lungs are an ecosystem with dynamic bacterial presence.
- Altered lung defenses in disease promote dysbiosis and pathogen blooms.
- The role of novel respiratory colonizers requires further investigation.
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