Fig 9.

Intranasal prophylaxis with CpG ODN can protect against subcutaneous but not intranasal challenge with Y. pestis strain CO92. (A) Survival of mice treated intranasally with 50 μg CpG ODN 1 day prior to intranasal infection with approximately 1 × 10⁴ CFU Y. pestis CO92. Control mice were treated with PBS diluent. The data were pooled from 2 independent experiments (n = 15 mice per group). (B) Survival of mice treated intranasally with 50 μg CpG ODN 1 day prior to subcutaneous infection with 10 CFU Y. pestis CO92. Control mice were treated with PBS diluent. The data were pooled from 2 independent experiments (n = 20 mice per group). (C) Survival of mice treated with 50 μg CpG ODN at the indicated time points relative to subcutaneous infection with 10 CFU Y. pestis CO92. Control mice were treated with PBS diluent at both time points, and PBS was administered as an additional sham treatment to mice receiving only one CpG ODN treatment. The data were pooled from 2 independent experiments (n = 19 to 20 mice per group).