FIG 4.

Adoptive transfer of wild-type but not IFN-γ-deficient CD8⁺ T cells lessens bacterial burden in Rag1 knockout mice following NMI infection. Rag1 knockout mice received 5 × 10⁶ CD8⁺ T cells from WT or IFN-γ knockout mice at 24 h prior to i.p. infection with 1 × 10⁷ NMI organisms. Disease severity was assessed at 14 dpi. (A) Relative body weight was determined throughout infection to monitor disease severity. (B) Splenomegaly was determined as a ratio of spleen weight to body weight. (C) Bacterial burden in the spleen was determined by real-time PCR and reported as log₁₀ C. burnetii com1 gene copy numbers. These data indicate that adoptive transfer of WT, but not IFN-γ-deficient, CD8⁺ T cells helps to control bacterial burden in mice following NMI infection. The data presented for each group are the average with standard deviation for four mice. Results were analyzed by one-way (B and C) or two-way (A) ANOVA with Tukey's multiple-comparison test for statistical significance. ***, P < 0.001; ****, P < 0.0001.