Why is it worth remembering the lung microbiome in ICU patients?

Area of Science:

• Microbiology
• Immunology
• Pulmonology

Background:

• Commensal microorganisms are vital for host homeostasis, not merely passive occupants.
• While gut, skin, and vaginal microbiomes are well-studied, the pulmonary microbiome's role remains largely unknown.
• The lung microbiome significantly influences host immune responses and presents potential therapeutic avenues.

Purpose of the Study:

• To explore the impact of the pulmonary microbiome on host immunity.
• To investigate the link between lung microbiome dysbunction and respiratory diseases.
• To consider microbiota-targeted therapies for intensive care unit (ICU) patients.

Main Methods:

• Analysis of gene expression modulation by the lung microbiome.
• Assessment of immune mediator concentrations (e.g., interleukins, chemokines).
• Evaluation of toll-like receptor-4 dependent responses in pulmonary macrophages.

Main Results:

• Lung microbiome modulates innate immunity gene expression.
• Increased concentrations of interleukin-5, interleukin-10, interferon-γ, and C-C motif chemokine ligand 11 observed.
• Altered toll-like receptor-4 dependent responses and antibacterial peptide production in mucus.

Conclusions:

• Pulmonary microbiome dysbiosis is implicated in asthma and chronic obstructive pulmonary disease (COPD).
• Pulmonary dysbiosis is also evident in critically ill patients.
• Microbiota-targeted therapy may offer future therapeutic strategies for ICU patients.