The role of serum in the production of tumor necrosis factor-a (TNF-a) by human monocytes stimulated with yeast-form Candida albicans was studied. Pre-exposure of C. albicans to human pooled serum enhanced both TNF-a mRNA and cytokine secretion compared with C. albicans preincubated with medium only. Serum factors involved were 130 kDa, were efficiently inhibited by D-mannose, and recognized both Ca11-dependent and -independent pathways. Preincubation of yeasts with rabbit mannose-binding protein (MBP) resulted in dose-related enhancement of TNF-a secretion, through a Ca11-dependent pathway inhibited by D-mannose. TNF-a levels were similarly induced in C. albicans preincubated with vitronectin and with serum. Ca11 depletion did not affect cytokine release, while Dmannose supplementation displayed inhibition. The latter effect was abolished after Ca11 depletion. These data call for an involvement of both MBP and vitronectin in the serummediated enhancement of TNF-a release upon stimulation of monocytes with yeast forms of C. albicans
Serum-mediated enhancement of TNF-alpha release by human monocytes stimulated with the yeast form of Candida albicans
ANGELETTI S;
1998-01-01
Abstract
The role of serum in the production of tumor necrosis factor-a (TNF-a) by human monocytes stimulated with yeast-form Candida albicans was studied. Pre-exposure of C. albicans to human pooled serum enhanced both TNF-a mRNA and cytokine secretion compared with C. albicans preincubated with medium only. Serum factors involved were 130 kDa, were efficiently inhibited by D-mannose, and recognized both Ca11-dependent and -independent pathways. Preincubation of yeasts with rabbit mannose-binding protein (MBP) resulted in dose-related enhancement of TNF-a secretion, through a Ca11-dependent pathway inhibited by D-mannose. TNF-a levels were similarly induced in C. albicans preincubated with vitronectin and with serum. Ca11 depletion did not affect cytokine release, while Dmannose supplementation displayed inhibition. The latter effect was abolished after Ca11 depletion. These data call for an involvement of both MBP and vitronectin in the serummediated enhancement of TNF-a release upon stimulation of monocytes with yeast forms of C. albicansI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
