Figure 2. Weight change and bacterial clearance of C. muridarum infected wild type vs. TLR2-deficient mice.

C57BL/6 or TLR2 KO mice on the same background were intranasally inoculated with PBS (mock; N = 6) or 2.5×10⁴ IFU/mouse of C. muridarum Nigg (N = 8), as described in the Methods. (A) Mice were weighed daily for 9 days post infection. Shown above is the weight change relative to the starting weight of each individual mouse (weight day X/weight day 0). Significance is as follows: p = 0.0474 infected BL/6 vs infected TLR2 KO over time, using RM ANOVA as described in the methods using a two-factor RM ANOVA with post hoc test. No significant difference in weight was observed between uninfected strains. (B) Mice were infected with 5×10³ IFU C. muridarum Nigg, and were euthanized on day 2, 4, 7, 14 and day 20. Quantitative bacterial cultures were determined from whole lung homogenates, as described in the Methods. Quantitative culture data was confirmed by quantitative PCR (data not shown). Statistical analysis of the infectious burden over time using a Mann-Whitney U test was not significant. This figure is representative of three independent experiments performed.