FIG 4.

Contributions of inflammasome components to host control of intracellular R. australis in macrophages. BMMs of B6, ASC^−/− (A), and TLR4^−/− (B) mice were infected with R. australis at an MOI of 2. Fresh medium was replaced every 24 h after infection. (C) RAW 264.7 macrophages were cultured and treated with 10 ng/ml recombinant IL-1β at the time of infection. At 48 h p.i., cells were washed, and the total DNA was extracted. The concentrations of rickettsiae in these mouse macrophages were evaluated by quantitative real-time PCR at 48 h p.i. The number of citrate synthase (CS) gene copies per ng of genomic DNA represents the quantity of rickettsiae. Data represent two independent experiments. *, P < 0.05.