Effect of pathogenic yeasts on human platelet aggregation.
We investigated the effects of Candida albicans, Cryptococcus neoformans and the respective culture supernatants on human platelet aggregation (PA). Both yeasts were unable to aggregate the platelets directly. On the other hand, cells of these yeasts significantly (P < 0.01) inhibited PA at concentrations equal to or higher than 1 x 10(6) cells/mL for C. albicans and equal to or higher than 1 x 10(5) cells/mL for C. neoformans. When the supernatants of one-week broth cultures were added to the activated platelets no inhibition in aggregation was observed. Apparently somatic components of these yeasts, but not their metabolic products, exert an antagonistic effect on the aggregation of human platelets, possibly aiding the fungi in their evasion of the microbicidal defense system during vascular dissemination.
Carvalho Neiva
Teresinha de Jesus
Tde J
Federal University of Santa Catarina, Centre of Health Science, Florianópolis, SC, Brazil. neiva@ccs.ufsc.br
dos Santos
Jairo Ivo
JI
D002176:Candida albicans / Q000276:immunology / Q000502:physiology*; D003455:Cryptococcus neoformans / Q000276:immunology / Q000502:physiology*; D006801:Humans; D010974:Platelet Aggregation / Q000502:physiology*