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Updated: Jun 23, 2026
06:22
Surfactant Depletion Combined with Injurious Ventilation Results in a Reproducible Model of the Acute Respiratory Distress Syndrome (ARDS)
Published on: April 7, 2021
Airspace miR-146a levels in ventilated patients decrease with age and correlate with mortality
Biorxiv : the Preprint Server for Biology
|June 22, 2026
Summary
MicroRNA-146a levels in alveolar fluid, not plasma, correlate with outcomes in acute respiratory distress syndrome (ARDS). Lower levels in the lungs indicate higher mortality risk, especially in older adults.
Area of Science:
- Pulmonary Medicine
- Molecular Biology
- Biomarker Discovery
Background:
- Acute respiratory distress syndrome (ARDS) is a severe condition with high mortality.
- Identifying reliable biomarkers for ARDS prognosis and treatment is crucial.
- Plasma biomarkers may not accurately reflect lung-specific disease processes in ARDS.
Purpose of the Study:
- To investigate the utility of microRNA-146a (miR-146a) as a biomarker in ARDS.
- To determine if miR-146a levels in different bodily fluids correlate with patient outcomes.
- To explore the potential of heat moisture exchange (HME) filter fluid as a novel biospecimen source.
Main Methods:
- Measured miR-146a expression using digital droplet PCR in plasma, bronchoalveolar lavage (BAL) fluid, and HME fluid from ARDS patients.
- Analyzed miR-146a levels in relation to patient age, mortality, and other clinical outcomes.
- Compared miR-146a detectability and correlation with outcomes across the different fluid compartments.
Main Results:
- miR-146a was detectable in plasma, BAL fluid, and HME fluid.
- Lower miR-146a expression in BAL fluid and HME fluid was significantly associated with increased mortality and older age.
- miR-146a levels in plasma did not correlate with patient outcomes.
- Demonstrated the feasibility of measuring nucleotides in HME fluid.
Conclusions:
- Alveolar space measurements of miR-146a, but not plasma, are associated with ARDS patient outcomes.
- HME filter fluid represents a promising, non-invasive source for alveolar biomarker assessment in ARDS.
- Findings highlight the importance of analyzing biomarkers within the specific microenvironment of the lung.
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