[A new pathogen of farmer's lung disease-Streptomyces thermohygroscopicus and its antigen analysis related to diagnosis].

Streptomyces thermohygroscopicus (H9-4) is a new pathogenic strain of farmer's lung disease (FLD) which is wide spread in Hubei province. Experimental "farmer's lung" in mice C87 was induced with the metabolites of this strain. Rabbits also suffered from the same FLD with characteristic pathogenic changes after aspiration of dried powder of this organism. For analysis of antigen fractions, with diagnostic value from this crude antigen of H9-4 SDS-PAGE and immunoblotting technic was employed and sera of 82 patients suffering from FLD from several districts were tested with this technic and the results revealed IgG antibodies could recognize the antigen-peptides from Mw 73 Kd and 68 Kd which were main antigen-peptides or pathogenic antigen to the disease. Sera of patients with present illness could recognize the peptide antigen between 11-90 Kd. In addition, all serum samples from healthy controls and from patients suffering from other respiratory diseases gave negative results. Therefore we conclude that SDS-PAGE and immunoblotting technic can be used in the diagnosis of FLD.