Figure 6

Survival curves of mice infected with pneumococci and pre-treated with; i) 2× intranasal doses of sterile PBS (PBS +infection) and ii) 2× intranasal doses of 500 μg ultrafine-carbon black (UF-CB + infection). Animals treated with PBS alone or UF-CB alone had no morbidity (data not shown). Data shown are representative of >4 separate experiments done at different times each with 10 animals per group. In the data plotted, median survival of PBS treated mice was 30 h. In contrast, median survival in UF-CB treated mice was 48 h (hazard ratio 8.5 (95% CI 2.0 to 36), P < 0.001 by log rank test).