Apoptosis of phagocytic cells induced by Candida albicans and production of IL-10

Macrophages co-incubated with Candida albicans strain CRI in vitro showed early signs of apoptosis, but evolved to necrosis after 2 h. In this study, we investigated whether strain CRI caused apoptosis or necrosis of macrophages after its inoculation into mice peritoneal cavity, and whether this correlated with the secretion of IL-10. Peritoneal macrophages from mice that received an inoculum of C. albicans CR 1 showed signs of apoptosis and necrosis from 30 min to 2 h afterwards, whereas heat-killed C albicans did not cause those effects. IL-10 production was low during the first 6 h post-infection, when macrophages predominated in the peritoneal exudate, whereas its higher production after 24 h correlated with an increase of neutrophils in the exudate. Treatment of CRI with pepstatin (an inhibitor of proteinases) prevented the process of apoptosis and significantly reduced IL-10 production, suggesting that the increased production of IL-10 was caused by processes occurring during the initial phase of infection, such as apoptosis, necrosis and uptake of death cells. (C) 2004 Federation of European Microbiological Societies. Published by Elsevier B.V. All rights reserved.