Figure 1.

Control of LVS growth by wild-type LVS-immune splenocytes in (A) wild-type BMMØ and (B) BMMØ that lack the IFNγR. BMMØ from wild-type and IFNγR KO mice were infected with LVS at an MOI of 1:40 (bacterium-to-macrophage ratio). Infected BMMØs were cocultured with splenocytes from either uninfected mice (naive spleen), mice infected intradermally with LVS 4 wk previously (primed spleen), or no spleen cells (macrophages + LVS). Immediately after LVS infection of the BMMØs, splenocytes were added to the indicated wells at a ratio of 1:2 (splenocyte:BMMØ). 72 h after infection, the BMMØ were washed, lysed, and plated to determine the levels of intracellular bacteria. Values shown are the mean numbers of CFU/ml ± the SEM of viable bacteria (triplicate samples). Asterisks (*) indicate P values <0.01 as compared with cocultures containing naive spleen cells. These data are representative of five experiments of similar design.