Pathogenicity of Allescheria boydii for Mice

Abstract

Allescheria boydii and its imperfect state, Monosporium apiospermum, were studied to determine whether asexual or sexual strains might exhibit different pathogenic potentials for mice. Six different strains of the fungus were inoculated into mice by the intravenous, intracerebral, intraperitoneal, and intranasal routes. Cortisone-treated mice regularly developed infections after inoculation by any of the routes tested. Mice that had not been treated with cortisone were most susceptible to infection by the intravenous route and least susceptible to infection by the intranasal or intraperitoneal route; nevertheless, all animals that did not receive cortisone were considerably more resistant to infection by the fungus than were comparable groups of cortisone-treated animals. Pathogenicity of the fungus appears to be strain dependent and entirely unrelated to its sexual or asexual form. Studies made to determine accurate viable spore counts of the fungus revealed that the highest viable spore count was generally observed using Sabouraud dextrose agar or potato dextrose agar at an incubation temperature of 37 C for a period of 5 days.

Exoantigen test for identification of Petriellidium boydii cultures

“…We isolated some of the fungi from soil (19a) and also used clinical specimens from our institute. Other isolates were graciously furnished by Libero Ajello, Mycology Division, Centers for Disease Control, Atlanta, Ga., Robert Samson, Centraalbureau voor Schimmelcultures, Baarn, Holland, and David Lupan (14), Department of Microbiology, University of Reno, Reno, Nev. All of the cultures were maintained in sterile water at room temperature in our culture collection.…”

History of medical mycology in the united states.

“…Michael Cazin's students at the University of Iowa (117). The pathogenicity of this fungus was found to be related to both the sexual and asexual forms (262).…”

Humoral response to experimental petriellidiosis

“…Since these studies have been relatively unsuccessful, investigators have concluded that these fungi have little virulence for laboratory animals. On the other hand, our investigations of several isolates of P. boydii and M. apiospermum have shown that individual isolates are virulent for mice, although at considerably different 50% lethal doses (LD5o) (15). Mice were found consistently to be susceptible to a fulminating petriellidiosis when the intravenous route of infection was utilized.…”

“…Partial characterization of some antigens has been described (16). The LD50 values for P. boydii strains 801, 807, and 809 and M. apiospermum strains 806, 813, and 815 for intravenously inoculated mice were 2.95 X 104, 19.1 X 104, 10.0 X 104, 1.29 x 104, 0.95 X 104, and 3.72 x 104 spores, respectively (15).…”

“…Fungus spores were obtained from cultures grown on Czapek dextrose agar at room temperature. Techniques for harvest and separation of spores from mycelial fragments have been described previously (15). Viability of spores was determined by using pour plates of potato dextrose agar and incubation at 370C.…”