FIG 6.

AMs support the assessment of innate immunity against C. burnetii phase II using knockout mice in the C57BL/6 mouse genetic background. Primary AMs from wild-type C57BL/6 mice and Nos2^−/− (A), Ifng^−/− (B), and Il4^−/− (C) mice were infected with C. burnetii phase II (MOI, 3), and bacterial multiplication was evaluated by quantification of the genomic DNA by qPCR after 0 (4 h after infection), 3, 6, 9, and 12 days of infection. The y axis represents the difference in the base 10 logarithm between the genomic quantity X at time t [logX(t)] and the quantity X at time zero (T₀) [logX(0)]. Cells treated with RIF were used as a negative control of bacterial replication. (Insets) Amount of C. burnetii genomic DNA present in cells after 4 h of infection. The data shown are the means ± standard errors from one representative experiment out of three independent experiments preformed. *, P < 0.05 (two-way ANOVA).