FIG. 3.

Effects of CD40-CD154 blockade on IL-10 and IL-12 levels after primary stimulation. PBL were stimulated with autologous L. major-infected adherent cells (macrophages) in the presence or absence of anti-CD154 or an isotype control antibody (mouse IgG1). After 7 days, supernatants were harvested and concentrations of IL-10 (A) and IL-12 (B) were determined by ELISA. The data for individual donors (●) and means (bars) are presented with background cytokine levels subtracted. Background equaled the concentration of cytokine when PBL were stimulated with uninfected adherent cells and ranged 10 to 30 pg/ml for both IL-10 and IL-12. The concentrations of IL-10 and IL-12 observed in cultures treated with isotype control antibody were equivalent to those in cultures with no added antibody (data not shown). ∗, statistically different (P < 0.05).