TABLE 2.
Mortality recorded after intratracheal P. aeruginosa challenge of CF mice and BALB/c mice with the mucoid strain +QS (NH57388A), the nonmucoid strain −QS (NH57388B), and the nonmucoid strain +QS (NH57388C)a
Parameter | Expt 1
|
Expt 2
|
Expt 3
|
Expt 4
|
||||
---|---|---|---|---|---|---|---|---|
CF mice (mucoid +QS NH57388A) | BALB/c mice (mucoid +QS NH57388A) | BALB/c mice (mucoid +QS NH57388A) | BALB/c mice (nonmucoid −QS NH57388B) | BALB/c mice (mucoid +QS NH57388A) | CF mice (mucoid +QS NH57388A) | CF mice (nonmucoid +QS NH57388C) | CF mice (nonmucoid −QS NH57388B) | |
Mortality (no. of animals dying/total no. tested) at day: | ||||||||
1 | 1/26 | 0/15 | 1/22 | 1/15 | 1/20 | 0/13 | 2/15 | 1/13 |
2 | 3/26 | 0/15 | 1/22 | 1/15 | 1/20 | 2/13 | 3/15 | 0/13 |
3 | 4/26 | 0/15 | 4/22 | 1/15 | 1/20 | 3/13 | 2/15 | 1/13 |
4 | 4/26 | 0/15 | 3/22 | 0/15 | 1/20 | 0/13 | 1/15 | 0/13 |
5 | 5/26 | 0/15 | 2/22 | 0/15 | 0/20 | 1/13 | 1/15 | 0/13 |
6 | 0/26 | 0/15 | 1/22 | 0/15 | 0/20 | 0/13 | 0/15 | 1/13 |
7 | 0/26 | 0/15 | 0/22 | 0/15 | 0/20 | 0/13 | 0/15 | 0/13 |
Total | 17/26 | 0/15 | 12/22 | 3/15 | 4/20 | 6/13 | 9/15 | 3/13 |
Mortality (%) | 65*** | 0 | 55* | 20 | 20 | 46 | 60** | 23 |
95% Confidence interval | 4-83 | 0-22 | 32-76 | 4-48 | 6-44 | 19-75 | 32-84 | 5-54 |
Expt 1, inoculum of 5 × 106 CFU/lung (bacteria were instilled with crude alginate); Expt 2, inoculum of 5 × 107 CFU/lung (bacteria were instilled with crude alginate); Expt 3, inoculum of 5 × 107 CFU/lung (bacteria were instilled with purified alginate); Expt 4, inoculum of 5 × 106 CFU/ml (bacteria were instilled with purified alginate).
* and **, P < 0.05 compared to strain NH57388B resuspended in culture supernatant (crude alginate [*]) or in purified alginate (**); ***, P < 0.001 compared to BALB/c mice.