Histopathology of experimental invasive pulmonary aspergillosis in rats: pathological comparison of pulmonary lesions induced by specific virulent factor deficient mutants

摘要

An experimental rat model of pulmonary aspergillosis was used to study differences in histological features induced by 3 Aspergillus fumigatus strains, mutants devoid of exocellular protease and rodlet and their parental strain. There was no difference in mortality of mice after intravenous injection of these 3 strains, although histopathological features in the lungs of infected mice were significantly different. Five days after infection with the rodletless mutant, pulmonary lesions were limitedand inflammatory responses were weak in comparison to those induced by both the mutant devoid of exocellular protease and the parental strain. It is suggested that the rodlet layer in A. fumigatus conidia may be important in the pathophysiology of aspergillosis in eliminating host neutrophils and macrophages in the early stage of the infection.