Detection of antigens in lung biopsies by immunoperoxidase staining in extrinsic allergic bronchiolo-alveolitis (EABA).

Open lung biopsy specimens of 14 patients with extrinsic allergic bronchiolo-alveolitis (EABA) were studied by immunoperoxidase staining with avidin-biotin-complex method using nonconjugated antisera to Micropolyspora faeni, Thermoactinomyces vulgaris, Aspergillus fumigatus, and Aspergillus umbrosus. Antigenic intracellular material was found in macrophages and giant cells of granulomas in the lung tissue of 8 patients. This finding supports the hypothesis which suggests that macrophages and T-lymphocytes contribute to the tissue injury in EABA.