Figure 3: The effect of intranasal immunization with PspA plus each TLR against on the bacterial densities in Lung tissue (A) and blood (B) at 24 h post-challenge with the S. pneumoniae WU2 strain. An invasive dose of 2 × 107 cfu / mouse was nasally administered to mice that had been previously immunized with either PspA plus each TLR agaonist or PspA alone. Mice were euthanized to obtain lung tissues or blood from infected mice at the indicated time-point after bacterial challenge, and quantitative bacterial cultures of lung tissue or blood were performed. Values represent the Log10 cfu / g or Log10 cfu / ml (mean ± S.D.) for six mice per group. *p < 0.0001, when compared with mice that were nasally immunized with PspA alone.