FIG. 6.

Effect of IL-10 on C. burnetii replication in Q fever endocarditis. (A) Monocytes from patients with acute Q fever or ongoing Q fever endocarditis were incubated with C. burnetii at a bacterium-to-cell ratio of 200:1, and the infection index was assessed at days 0, 6, and 12 as described in the legend to Fig. 1A. (B and C) Infected monocytes from patients with acute Q fever (B) or from patients with Q fever endocarditis (C) were cultured in the presence of neutralizing anti-IL-10 Abs or control serum (10 μg/ml), and the infection index was determined after 6 and 12 days relative to day 0.