ANTIBODIES AGAINST ASPERGILLUS FUMIGATUS IN BRONCHIAL SECRETIONS FROM PATIENTS WITHOUT ASPERGILLOSIS

Antibodies to Aspergillus fumigatus were investigated by indirect immunofluorescence (IIF) and enzyme-linked immunosorbent assay (ELISA) in bronchial secretions (BS) and sera from 40 patients with neoplasia, lung infiltrates of non-fungal aetiology or chronic bronchitis. By IIF, IgG aspergillus antibodies were found in 23 samples of BS (58%) (titre range 10–40) and in all 40 sera (titre range 10–1280). IgA aspergillus antibodies were detected in 33 samples of BS (83%) (titre range 10–160) and in 33 sera (83%) (titre range 10–40). IgM aspergillus antibodies occurred in 2 samples of BS (5%) (titre 10 and 40) compared with 35 sera (88%) (titre range 10–40). Antibodies with secretory component (SC) were detected in 20 of 39 BS samples tested (51%) (titre range 10–160). Significantly higher levels of IgA antibodies were detected by ELISA in BS than in serum (2p<0.05) and, conversely, significantly higher levels of IgG antibodies were found in serum than in BS (2p<0.001). Low levels of antibodies with SC were also detected in BS by ELISA. These results suggest that aspergillus antibodies are produced within the bronchopulmonary system in patients without aspergillosis.