FIG. 4.
SEA-specific IFN-γ, IL-2, IL-4, IL-5, IL-10, and TGF-β cytokine levels during the course of primary infection and reinfection with S. mansoni in two representative baboons. PBMC were cultured at 2 × 106/ml in the presence of 5 μg of SEA/ml, and supernatants were harvested at 24 and 96 h. Cytokine secretion in the primary infection was compared to that at the corresponding time points after infection (secondary infection); significant differences are indicated by asterisks (∗, P < 0.05; ∗∗, P < 0.01; ∗∗∗, P < 0.001). #, weeks after reinfection. Each time point represents the geometric mean of triplicate cultures ± the standard deviation. Arrows indicate the times of infection.