Induced sputum cell counts in healthy adults

Area of Science:

• Pulmonary Medicine
• Cell Biology
• Respiratory Health

Background:

• Induced sputum cell counts are a valuable tool for assessing airway inflammation.
• Interpreting these counts requires established normal values from healthy populations.
• Previous data on normal induced sputum cell differentials in healthy adults is limited.

Purpose of the Study:

• To determine the total and differential cell counts in induced sputum from a sample of healthy, non-smoking adults.
• To establish reference values for various immune cells and bronchial epithelial cells in healthy individuals.
• To investigate potential associations between cell counts and factors like gender and atopy.

Main Methods:

• 118 healthy non-smoking adults were recruited, with 96 providing adequate sputum samples.
• Sputum samples were processed within 2 hours for total cell count, viability, and differential cell counts.
• Cell differentials were determined using Wright-stained cytospins, with specific attention to eosinophils, neutrophils, macrophages, and lymphocytes.

Main Results:

• Mean total cell count was 4.1 x 10^6 cells/g with 69.6% viability.
• The differential count showed a predominance of macrophages (58.8%) and neutrophils (37.5%).
• Higher eosinophil proportions were observed in females and atopic individuals.

Conclusions:

• This study provides essential reference values for induced sputum cell counts in healthy adults.
• These established values will aid in the accurate interpretation of airway inflammation in clinical and research settings.
• Understanding normal cell profiles is critical for diagnosing and managing respiratory conditions.