Pathogenicity of basidiospores of Filobasidiella neoformans var. neoformans.
Basidiospores of Filobasidiella neoformans var. neoformans (progeny of Cryptococcus neoformans MT 100.1 x VR 45980) were able to induce cryptococcosis in Swiss albino mice if inoculated by intraperitoneal injection, nasal instillation or nasal spraying. The latter method, with the aid of a jet nebulizer, was first adopted to imitate the natural entrance of infectious particles. Using this method the small number of basidiospores (7 x 10(3)) could induce cryptococcosis in mice, while the higher number of the parental laboratory-grown yeast cells (1.5 x 10(6)) did not produce infections. By nasal instillation Cyclophosphamide (Cy)-treated mice were more susceptible to the basidiospores, showing 80% cryptococcosis (eight of 10). Seven of the eight infected mice had disseminated cryptococcosis. Immunocompetent mice were more resistant to basidiospore infection than Cy-treated mice, as 40% of that group developed only pulmonary cryptococcosis; none had disseminated infection. Thus, we propose that basidiospores are one form of the infectious propagules of F. neoformans var. neoformans which can cause cryptococcosis, particularly in immunocompromised people.
Sukroongreung
S
S
Department of Clinical Microbiology, Faculty of Medical Technology, Mahidol University, Bangkok, Thailand. mtssk@mahidol.ac.th
Kitiniyom
K
K
Nilakul
C
C
Tantimavanich
S
S
D000818:Animals; D001487:Basidiomycota / Q000254:growth & development / Q000472:pathogenicity*; D003453:Cryptococcosis / Q000382:microbiology* / Q000635:transmission; D003455:Cryptococcus neoformans / Q000254:growth & development / Q000472:pathogenicity*; D003520:Cyclophosphamide / Q000008:administration & dosage; D007121:Immunocompetence; D016867:Immunocompromised Host; D007166:Immunosuppressive Agents / Q000008:administration & dosage; D008172:Lung Diseases, Fungal / Q000382:microbiology* / Q000635:transmission; D051379:Mice; D013172:Spores, Fungal / Q000472:pathogenicity
D007166:Immunosuppressive Agents; D003520:Cyclophosphamide