ASP FI CD4-H2-LIKE T-CELL LINES IN ALLERGIC BRONCHOPULMONARY ASPERGILLOSIS( T)

Allergic bronchopulmonary aspergillosis (ABPA) is a hypersensitivity l ung disease caused by bronchial colonization with Aspergillus fumigatu s (Af) characterized by elevated serum total and Af-specific IgE level s and eosinophilia. In order to examine T-cell reactivity to Af antige ns, six T-cell lines were established from the peripheral blood of pat ients with ABPA to Asp f I, an 18 kd protein purified from Af extracts . The Asp f I-specific T-cell lines, analyzed by flow cytometry, were 100% CD3 + CD4 +. Lymphoproliferative responses of the T-cell lines we re specific for Asp f I stimulation, 28,999 cpm (stimulation index = 1 2.2), and showed no response to tetanus toroid stimulation 2178 cpm (s timulation index = 1.1) (p < 0.001). Furthermore, Asp f I-stimulated l ymphoproliferation was inhibited in two experiments by monoclonal anti -interleukin (IL)-4 antibody in a dose-response fashion, 78% and 84% i nhibition at 5% concentration of anti-IL-4. In contrast, anti-IL-2 ant ibody did nor inhibit Asp fl-stimulated proliferation. Asp fl-stimulat ed T-cell lines synthesized predominantly IL-4 (mean, 21.5 ng/ml) afte r 48 hours of culture, and nondetectable quantities of interferon-gamm a and IL-2. In summary Asp f I-specific T-cell lines established from patients with ABPA were characterized as being CD4 + T-H2-like in thei r cytokine synthesis pattern, and secreted IL-4 behaved in an autocrin e fashion, stimulating proliferation.