Altered expression of surface alpha-1,3-glucan in genetically related strains of Blastomyces dermatitidis that differ in virulence.
Recent studies of the dimorphic fungal pathogens Histoplasma capsulatum and Paracoccidioides brasiliensis have suggested a role in virulence for the cell surface carbohydrate alpha-(1,3)-glucan. To investigate a possible basis for alpha-(1,3)-glucan in the pathogenicity and virulence of the dimorphic fungus Blastomyces dermatitidis, we examined three genetically related strains of B. dermatitidis that differ in their virulence for mice: wild-type virulent strain ATCC 26199; mutant strain ATCC 60915, which is 10,000-fold reduced in virulence; and mutant strain ATCC 60916, which is avirulent. Immunologic quantitation of cell wall alpha-(1,3)-glucan revealed that the mutant yeasts were almost devoid of this sugar moiety, in contrast to the high concentration of alpha-(1,3)-glucan on the cell wall of the wild-type yeasts. These differences are discussed in relation to previous studies of yeast surface expression of the WI-1 antigen and recognition and binding of the related strains by human monocyte-derived macrophages.
Hogan
L H
LH
Department of Pediatrics, University of Wisconsin Medical School, University of Wisconsin Hospital and Clinics, Madison 53792.
Klein
B S
BS
D001758:Blastomyces / Q000737:chemistry / Q000235:genetics / Q000472:pathogenicity*; D005936:Glucans / Q000032:analysis*; D006801:Humans; D009154:Mutation; D014774:Virulence
D005936:Glucans; C045788:alpha-1,3-glucan