Particles in Exhaled Air (PExA): Clinical Uses and Future Implications

Area of Science:

• Pulmonary Medicine
• Respiratory Diagnostics
• Biomarker Discovery

Background:

• Assessing distal airway inflammation typically requires invasive procedures like bronchoscopy.
• There is a need for non-invasive methods to sample the distal airways for disease assessment.
• Particles in exhaled air (PExA) capture respiratory tract lining fluid (RTLF) from small airways.

Purpose of the Study:

• To introduce and evaluate the particles in exhaled air (PExA) device as a non-invasive tool for distal airway assessment.
• To demonstrate the potential of PExA in analyzing biomarkers for respiratory diseases.
• To establish PExA as an alternative to invasive airway sampling methods.

Main Methods:

• Utilizing the PExA device to capture particles (PEx) from exhaled air, ranging from 0.5-7 μm.
• Quantifying particle count and mass based on size.
• Analyzing PEx particles for targeted and untargeted metabolites and inflammation markers using various analytical platforms.

Main Results:

• The PExA device successfully captures distal airway particles containing RTLF.
• PEx particles can be analyzed for lung-specific inflammatory markers.
• The method allows for quantitative measurement of biomarkers relevant to lung pathophysiology.

Conclusions:

• The PExA device provides a non-invasive method for accessing distal airway components.
• PExA analysis enables the evaluation of inflammatory conditions such as asthma, COPD, ARDS, and viral infections.
• This approach offers a more accurate understanding of molecular-level pathophysiological changes in lung diseases compared to traditional methods.