Experimental Hypersensitivity Pneumonitis Induced by Fusarium kyushuense in Mice

Abstract

Experimental Hypersensitivity Pneumonitis Induced by Fusarium kyushuense in Mice: Koichi HARADA, et al. Department of Hygiene, Kumamoto University School of Medicine—A recently described Fusarium species, Fusarium kyushuense, was isolated from dead leaves of egg plant in a greenhouse where a female farmer who developed hypersensitivity pneumonitis (HP) with progressing lung lesions had been working. The freeze dried fungus was exposed to specific pathogen-free, 6-week-old female C57Black/6J mice under light ether anesthesia. Each mouse received 40μl of the suspended fungal solution by dropping it onto its nostrils in 5 consecutive days a week for 4 wk. The control group received 40μl of 0.1 M sterilized phosphate buffered saline. The mice were killed on the 4th day after the final exposure. The lung indices increased dose dependently in the fungus exposed mice groups. The specific IgG anti-F kyushuense levels in sera of the high dose group were significantly higher than in the control group (P<0.05 by Ryan''s multiple comparison test). Histologically, the lungs of both low and high dose groups showed signs of atelectasis with granulomatous lesions containing multinuclear giant cells and activated macrophages. This is the first report that mice developed HP induced by repeated exposure to freeze dried F kyushuense.