Histoplasma capsulatum yeast cells attach and agglutinate human erythrocytes.
The ability of yeast cells of Histoplasma capsulatum to attach and agglutinate human erythrocytes has been described. This is the first report involving these yeasts in the hemagglutination phenomenon. Results revealed that the yeast cells were able to bind to erythrocytes irrespective of blood groups and to agglutinate them when a high density of yeast cells was used. Assays on the inhibition of yeast attachment to erythrocytes were also performed, using sugar-treated yeast cells. Results indicate that galactose (Gal), mainly the beta-anomer, specially inhibited yeast attachment. Disaccharides (Gal-derivatives) and glycosaminoglycans containing Gal residues, mainly chondroitin sulfate C, promote this type of inhibition. In addition, preliminary data of inhibition assays also involved a probable ionic strength driven mechanism mediated by sialic acid and heparan sulfate, suggesting that yeast binding to erythrocytes could be associated with negative charges of both molecules.
Department of Microbiología-Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, México City, México. emello@servidor.unam.mx
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Taylor
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Duarte-Escalante
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Pérez
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Zenteno
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Toriello
D001789:Blood Group Antigens; D002448:Cell Adhesion; D002809:Chondroitin Sulfates / Q000378:metabolism; D004187:Disaccharides / Q000378:metabolism; D004903:Erythrocyte Aggregation; D004912:Erythrocytes / Q000382:microbiology*; D005690:Galactose / Q000378:metabolism; D006025:Glycosaminoglycans / Q000378:metabolism; D006384:Hemagglutination; D006497:Heparan Sulfate / Q000737:chemistry; D006658:Histoplasma / Q000472:pathogenicity*; D006801:Humans; D019158:N-Acetylneuraminic Acid / Q000737:chemistry
D001789:Blood Group Antigens; D002809:Chondroitin Sulfates; D004187:Disaccharides; D005690:Galactose; D006025:Glycosaminoglycans; D006497:Heparan Sulfate; D019158:N-Acetylneuraminic Acid