Susceptibilities of Cryptococcus neoformans strains to platelet binding in vivo and to the fungicidal activity of thrombin-induced platelet microbicidal proteins in vitro.

In this study we investigated the interactions between capsular and acapsular strains of Cryptococcus neoformans and blood platelets. In vivo microscopic observation of blood samples from mice inoculated with C. neoformans yeast cells demonstrated that encapsulated and nonencapsulated yeast cells disappeared quickly from the bloodstream and that platelets were attached solely to yeast cells of the nonencapsulated strains. In vitro we observed that only the acapsular strains were susceptible to the fungicidal activity of thrombin-induced platelet microbicidal proteins.