TLR2 signaling is important in <i>Francisella</i> invasion of primary cells.

<p>(A) Peritoneal macrophages derived from WT, TLR2KO and TLR4KO mice were exposed to <i>F. tularensis</i> LVS (MOI=20) for 0-120 min and then lysed. Total protein and phosphorylated p38 (Thr¹⁸⁰/Tyr¹⁸²) and ERK1/2 (Thr²⁰²/Tyr²⁰⁴) were assessed by Western analysis. Samples analyzed contained an equal amount of protein. Unstimulated cells served as negative controls. All gels are representative of three to five independent experiments. (B) Peritoneal macrophages derived from WT and TLR2KO mice were exposed to freshly harvested <i>F. tularensis</i> LVS (MOI=20) for 90 min to assess bacterial invasion. Values are the mean ± SEM of 5 independent experiments, each done in triplicate; **p < 0.001; *p < 0.05 compared with infected control cells treated with DMSO.