Figure 6.

In a mouse sepsis model, the deficiency of pfbA increases the virulence and TNF-α level in blood but decreases the bacterial burden in the lung and liver. CD-1 mice were infected intravenously with the S. pneumoniae TIGR4 wild type or ΔpfbA strain (3–6 × 10⁶ CFUs). (A) Mouse survival was monitored for 14 days. Statistical differences between groups were analyzed using a log-rank test. (B) CD-1 mice were infected intravenously with the S. pneumoniae TIGR4 wild type or ΔpfbA strain (6–9 × 10⁶ CFUs). Plasma samples were collected from these mice at 24 h after infection. Values are presented as the mean of 16 or 18 samples. Vertical lines represent the median ± IQR. Statistical differences between groups were analyzed using Mann-Whitney's U-test. (C) The bacterial burden in the blood, brain, lung, and liver were assessed after 24 h of infection. The median and IQR values are represented by vertical lines. All mice were perfused with PBS after blood collection, organ samples were collected. Statistical differences between groups were analyzed using Mann-Whitney's U-test. The mouse survival data were obtained from three independent experiments, and the TNF-α level and bacterial burden values obtained from two independent experiments were pooled.