[Extrinsic allergic alveolitis: IgG subclass reactivities and monoclonal antibodies against Micropolyspora faeni and Aspergillus fumigatus].

IgG-subclass reactivities to Micropolyspora faeni of farmer's lung patients and exposed persons were investigated. Additionally, specific IgG and IgE antibodies of patients suffering from IgE-mediated allergy and extrinsic allergic alveolitis to Aspergillus fumigatus and allergic bronchopulmonary aspergillosis (ABPA) were examined. Antibody reactivities of patients were compared with reactivities of monoclonal antibodies raised against M. faeni and A. fumigatus, respectively. The results indicate a special importance of specific IgG2 reactivity for serologic diagnosis. Monoclonal antibodies raised against M. faeni and A. fumigatus recognize components which induce antibody production in patients as well. Reactivities of monoclonal antibodies with different batches of A. fumigatus extract show the variability of these antigen preparations and illustrate the need for standardization.