Aspergillus ribotoxins react with IgE and IgG antibodies of patients with allergic bronchopulmonary aspergillosis.

Asp f I has been identified as a major allergen of Aspergillus fumigatus and shows amino acid sequence homology with the mitogillin family of cytotoxins. In this study we compared the various cytotoxins from Aspergillus species for their reactivity with immunoglobulin E (IgE) and immunoglobulin G (IgG) antibodies in the serum samples of patients with allergic bronchopulmonary aspergillosis. Elevated levels of IgE and IgG antibodies to all A. fumigatus antigens and ribotoxins were demonstrated in a majority of ABPA patients as compared with allergic patients with asthma and normal subjects. In approximately 75% of patients with allergic aspergillosis, IgE antibody to ribotoxins showed marked elevation, whereas in the remaining patients it was below the baseline, although crude A. fumigatus antigen showed higher specific serum IgE. These results suggest that cytotoxins play a major role in the pathogenesis of allergic bronchopulmonary aspergillosis.