Figure 2.

M3^−/− mice exhibit increased susceptibility to LM infection compared with WT and K^b−/−D^b−/− mice. (A) Increased bacterial burdens in the spleens and livers of LM-infected M3^−/− mice. M3^−/−, K^b−/−D^b−/−, and WT mice were infected i.v. with 5 × 10³ CFU of LM. Bacterial burdens in the spleens and livers were determined at indicated time points after infection. Data are presented as the mean ± SEM from six mice per group per time point. Statistically significant differences between WT and M3^−/− mice (N6) are indicated. At day 7 of infection, the bacterial burdens in the spleens of LM-infected mice were below the detection limit. (B) Enhanced susceptibility of M3^−/− mice to LM. M3^−/− mice (N10) and WT controls were infected with LM at the dose of 5 × 10⁴ CFU. The survival of the mice was monitored daily up to 7 d after infection. Results are from 11 mice per group.