Inflammatory cell influx into ozone-exposed guinea pig lung interstitial and airways spaces.

As a model of non-immunological lung inflammation, guinea pigs were exposed to 2.0 ppm ozone for 4 hours. Polymorphonuclear leukocytes (PMNs) rapidly accumulated in lung interstitium but declined from 147 +/- 34 million cells to control values (33 +/- 6 million cells) within the first 24 hours. Bronchoalveolar lavage (BAL) recovered PMNs were maximal by 3-6 hours (4 +/- 1 million cells) and remained elevated for 3 days. Macrophage numbers were doubled in lavageable spaces but those in interstitium increased by only a third at 2 days post-exposure. By 7 days post-exposure BAL macrophages had declined to control values of 12 +/- 2 million cells while those in interstitium remained elevated through 14 days. These data demonstrate that BAL does not necessarily reflect cellular changes in lung interstitium.