FIG. 1.

CMi leads to an inhibition of NO production by IFN-γ-activated-microglia and may be correlated with PGE₂ secretion by astrocytes. (A) Nitrite concentration was determined by the Griess reaction in the culture supernatants. Microglia cells were activated with IFN-γ (500 U/ml) for 24 h in the presence of CMi or CMc. Controls consisted of microglia cells cultured in the presence or absence of IFN-γ. (B) Supernatants of 48-h-infected astrocytes (5:1) were collected and tested for PGE₂ using an enzyme immunoassay. Astrocytes were activated with IFN-γ (200 U/ml) in the presence or absence of the parasite. These data represent the means + standard deviations (error bars) of three independent experiments. Symbols: *, P < 0.05; **, P < 0.01.