2-DIMENSIONAL PROTEIN-PATTERNS OF BRONCHOALVEOLAR LAVAGE FLUID FROM NONSMOKERS, SMOKERS, AND SUBJECTS EXPOSED TO ASBESTOS

Background - Bronchoalveolar lavage (BAL) fluid contains a large numbe r of proteins which comprise a potential resource for studying respira tory effects due to occupational and environmental exposures. A study was undertaken to compare protein patterns of BAL fluid from nonsmoker s, smokers, and subjects exposed to asbestos. Methods - BAL fluid samp les were analysed with two dimensional gel electrophoresis (2-DE). The separated proteins were detected, quantified, and pattern-matched bet ween different individuals with a computerised imaging system designed for evaluations of 2-DE patterns. Results - About 200 different prote in spots were detected in each sample of BAL fluid. As is the case wit h blood plasma, the BAL fluid samples contained large amounts of album in, transferrin, and immunoglobulins. Higher levels of basic proteins were found in smokers than in non-smokers, while subjects exposed to a sbestos had increased amounts of several high molecular weight protein s as well as basic proteins. Lower levels of albumin and higher levels of immunoglobulins were found in smokers than in nonsmokers, while hi gher levels of transferrin were found in asbestos exposed subjects tha n in unexposed subjects. Moreover, in the group exposed to asbestos di fferences were found between patients with pleuritis and patients with pleural plaque, and one protein spot was found only in two patients w ith progressive pleural disease. Conclusion - These results suggest th at both smokers and asbestos exposed subjects have significant changes in their airway protein expression compared with non-smokers and unex posed subjects. It is inferred that analysis of protein patterns in th e BAL fluid with 2-DE may be used to detect and characterise, at a mol ecular level, respiratory effects due to occupational and environmenta l exposures.