Mice lacking TNF-α are partially sensitive to CO92Δ yopH infection. B6129F2 control mice or B6;129S-Tnftm1Gkl/J (TNF-α-/-) mice were infected IN with 2 × 104 CFU of CO92 or CO92ΔyopH and then monitored for survival over a ten day period. A) TNF-α-/- mice are sensitive to CO92ΔyopH infection. B) Both TNF-α-/- mice and control mice are sensitive to CO92 infection. Data was analyzed by log-rank analysis and significant comparisons indicated. Data is combined from two independent experiments with 5 mice per group.