TLR2- or MyD88-signaling–impaired OT-1 T cells show a diminished ability to clear a L monocytogenes infection. (A) Purified OT-1, TLR2−/−OT-1, and MyD88−/−OT-1 CD8 T cells (2.5 × 105) were intravenously injected into WT mice, followed by intravenous injection with 1 × 104 CFU LM-OVA 1 day later. For the determination of bacterial burdens in mice, spleens were collected at various time points after infection and homogenized in distilled water, and serial dilutions of homogenates were cultured on BHI agar. (B) MyD88−/− mice were injected intravenously with OT-1, TLR2−/−OT-1, and MyD88−/−OT-1 CD8 T cells, followed by infection with LM-Ova 1 day later. Five days later, spleens were collected, and the bacterial plaques were counted. Circles represent CFUs per spleen of individual mice. The results shown are the combination of 3 independent experiments, with 3-4 mice per group. Crosses represent mice that succumbed to bacterial challenge before assessing bacterial load. Changes in CFUs were analyzed by ANOVA; *P < .05, **P < .001.
