In vitro synthesis of Alternaria allergens and their recognition by murine monoclonal and human IgE antibodies

Background: Allergic reactions to fungal allergens, including Alternaria, are common clinical problems. Reagents used for diagnosis and therapy of fungal allergy are complex and variable mixtures. Standardized reagents are difficult to achieve due to batch to batch variability in these biologic products, Although several Alternaria allergens have been isolated, their production by current methods is laborious. The introduction of molecular biology into allergy research has led to the molecular cloning of several allergens which may culminate in improved methods of treatment. Objective: This report describes the development of techniques that will lead to the molecular cloning of Alternaria allergens. Methods: We isolated the poly (A)(+)-messenger RNA from Alternaria, produced proteins in vitro and probed them for binding to murine monoclonal antibodies directed against Alternaria. In addition, we examined the ability of the translated proteins to bind IgE from the sera of Alternaria-sensitive individuals. Results: We synthesized at least 20 proteins ranging in molecular weight from 2 to 90 kD using in vitro techniques. The translated proteins were detected by both murine monoclonal and human IgE antibodies. Conclusions: Alternaria allergens can be synthesized in vitro by molecular biology techniques. Such techniques will be used in the development of cDNA libraries for the production of Alternaria allergens by recombinant DNA methods.