VARIOUS CANDIDA AND TORULOPSIS SPECIES DIFFER IN THEIR ABILITY TO INDUCE THE PRODUCTION OF C3, FACTOR-B AND GRANULOCYTE-MACROPHAGE COLONY-STIMULATING FACTOR (GM-CSF) IN HUMAN MONOCYTE CULTURES

The incidence of infections with Candida albicans and also with non-al bicans yeast species is increasing rapidly, particularly in immunocomp romised patients. Eight Candida and Torulopsis species were compared f or their ability to stimulate production of complement components C3 a nd factor B by monocytes. In addition, the release of granulocyte-macr ophage colony-stimulating factor (GM-CSF) was determined, because this cytokine affects monocyte complement production. The highest ranked p athogenic yeasts, i.e., C. albicans, C. tropicalis and C. parapsilosis , were the most effective inducers of C3, factor B and GM-CSF producti on. C. krusei and T. glabrata showed intermediate activity, whereas C. kefyr, C. guilliermondii and T. candida had only a moderate stimulato ry effect on C3 production and did not affect either factor B or GM-CS F release. The stimulated cytokine and complement production in respon se to the yeasts was highly variable in monocytes from different donor s, but there was a consistent inverse relationship between C3 and GM-C SF concentrations in the monocyte supernates. This is in agreement wit h the previously described suppressive effect of GM-CSF on yeast-induc ed C3, but not factor B production. The monocyte responses elicited by a specific yeast species may be linked to its pathogenicity, and may also explain the predilection of some yeasts for particular underlying diseases.