ANALYSIS OF INDUCED SPUTUM AFTER AIR AND OZONE EXPOSURES IN HEALTHY-SUBJECTS

Exposure of healthy subjects to ozone is associated with increases in cellular and biochemical markers of inflammation in bronchoalveolar la vage fluid. To determine if analysis of induced sputum might similarly reveal the pulmonary inflammatory effects of ozone exposure, we perfo rmed cellular and biochemical analysis of induced sputum collected 4 h r after air and ozone (0.4 ppm for 2 hr) exposures from 10 healthy sub jects (age 30.0 +/- 5.0 years; 5 females) in a randomized crossover st udy in which exposures were separated by 2 weeks. We found that the to tal number of nonsquamous cells was significantly higher after ozone e xposure than after air exposure (7.4 vs 3.9 x 10(5)/ml, P < 0.05) as w as the percentage of the nonsquamous cells that were neutrophils (80.0 +/- 7.0% vs 51.0 +/- 20.0%, P < 0.05) and the levels of myeloperoxida se in the sputum fluid phase (1.6 +/- 0.6 vs 1.3 +/- 0.6 mu g/ml, P < 0.05). In addition, IL-6 and IL-8 levels were higher after ozone than after air exposures, but not significantly so (44.5 +/- 32.4 pg/ml vs 26.8 +/- 30.7 pg/ml, P = 0.11; 1.5 +/- 0.5 ng/ml vs 1.1 +/- 0.6 ng/ml, P = 0.09). Mucin-like glycoprotein levels were also not significantly different between exposures (1.6 +/- 0.9 mg/ml vs 1.3 +/- 1.0 mg/ml, P = 0.26). We conclude that analysis of induced sputum is a useful non invasive method for studying the pulmonary response to ozone exposure in healthy subjects. (C) 1995 Academic Press, Inc.