Cryptococcus neoformans and its cell wall components induce similar cytokine profiles in human peripheral blood mononuclear cells despite differences in structure.

We studied the cytokine profile of peripheral blood mononuclear cells after stimulation with various cryptococcal strains or its purified cell wall components. After 3 h of stimulation, tumor necrosis factor (TNF) alpha levels were strongly increased, whereas interferon (IFN) gamma and interleukin (IL) 10 levels were increased only slightly, or not at all (respectively). In contrast, after 18 h, TNF-alpha and IFN-gamma levels were (strongly) decreased, whereas the IL-10 levels were increased. The IL-1beta, IL-6 and IL-8 levels were equally high throughout the experiment. In order to establish which of the cryptococcal envelope components contributed most to the observed cytokine profile induced by whole cryptococci, glucuronoxylomannan, galactoxylomannan and mannoproteins were purified and partially characterized biochemically. All cryptococcal components elicited a similar cytokine pattern despite the differences in structure.