Experimental allergic alveolitis in mice induced by Thermoactinomyces vulgaris.

A model of allergic alveolitis was developed in inbred mice. Antigen suspension prepared from Thermoactinomyces vulgaris was applicated intranasally in C3H/He mice. Lung histology, serum IgG and IgA antibodies and serum lysozyme were followed during the course of sensitization. The lung histology showed an increased number of intra-alveolar macrophages and leucocytes in sensitized mice. Interstitial peribronchiolar and perivascular infiltration of mononuclear inflammatory cells and a few granulomas were also detected. An increase in the prevalence as well as titers of IgG and IgA antibodies was recorded during sensitization. An elevation in serum lysozyme level was also observed in sensitized mice. The lung histology of control animals was essentially normal and no increase in antibody titers or lysozyme levels was detected. Intranasal application of antigen prepared from Thermoactinomyces vulgaris seems to produce in mice allergic alveolitis resembling human farmer's lung.