Figure 6. TNFα and IFNγ contribute to basal protection in B cell-deficient mice.
C57BL/6-backcrossed B cell-deficient μMT mice were infected intranasally with Y. pestis (10 LD-50; 2×105 CFU). On the day prior to infection, animals received control mAb (closed squares) or neutralizing mAb specific for TNFα and IFNγ (anti-TNF/IFN; open circles). (A) Treatment with cytokine-neutralizing mAb significantly increased the time to morbidity in naïve mice (p < 0.0001; n = 9 mice per group). (B) Treatment with cytokine-neutralizing mAb significantly increased the bacterial burden in lung and liver on day 3 after initiating infection (* p < 0.001 as determined by Student’s t-test; n = 9 mice per group). The bars depict the means. All data in this figure are pooled from two independent experiments.