FIG 7.

Autophagy, induced by an mTOR inhibitor, significantly promotes the infection of R. australis in BMMs. WT B6 BMMs were pretreated with rapamycin (50 nM) for 4 h and then infected with R. australis at an MOI of 2. At 30 min (A) and 48 h (B) p.i., the adherent cells were collected for quantification of intracellular bacteria after the cells were washed with PBS. Infection of R. australis in these treated and untreated BMMs was evaluated by quantitative real-time PCR. The number of rickettsial citrate synthase (CS) gene copies per nanogram of genomic DNA represents the concentration of rickettsiae. Each group included cells in at least 10 independent wells in each experiment. The data shown are the mean ± standard deviation (SD) from two independent experiments. *, P < 0.01; n.s., not significantly different.