Differential effects of iron load on basal and interferon-gamma plus lipopolysaccharide enhance anticryptococcal activity by the murine microglial cell line BV-2

Here we evaluated the influence of intracellular iron levels on the constit utive and interferon (IFN)-gamma plus lipopolysaccharide (LPS) enhanced ant icryptococcal activity by the murine microglial cell line BV-2. We demonstr ated chat iron loading via ferric nitrilotriacetate (FeNTA) resulted in a s ignificant increase in the constitutive levels of anticryptococcal activity , while the enhancing effects by IFN-gamma plus LPS were prevented. Accordi ngly, a major increase was observed in the levels of thiobarbituric reactiv e substance (TBARS) produced upon iron loading under basal conditions, wher eas IFN-gamma plus LPS treatment, that per se did not affect TEARS producti on, prevented by about 50% the enhancement otherwise occurring in response to iron loading. The potential involvement of multiple effector system and their relation to intracellular iron will be discussed. (C) 1999 Elsevier S cience B.V. All rights reserved.