Bronchial leukocyte proteinase inhibitor levels in bronchial washings in asthma patients.

To evaluate whether epithelial damage of airways in asthma could be related to diminished levels of the low molecular weight bronchial leukocyte proteinase inhibitor (BLPI) in airways, we determined BLPI in bronchial washings of 13 asthma patients and 13 healthy subjects, using a sensitive enzyme-linked immunoassay. The patients had asthma due to western red cedar and had bronchial washings done 24 to 48 hours after a mild to moderate asthmatic reaction induced by inhalation challenge. We did not find significant differences in BLPI concentrations in lavage fluid of asthma patients and healthy control subjects. The ratios of BLPI to albumin levels in bronchial washings appeared to be lower among asthmatic patients, but this difference was mainly due to an increase in albumin levels in lavage fluid in asthma. In addition, there were no significant differences in BLPI levels in washings obtained from main and segmental bronchi in both control subjects and asthma patients.