TABLE 1.
Protective responses in the lungs and spleens of BCG-vaccinated mice at 4 and 12 weeks postchallenge with different M. tuberculosis strains
| Infection straina | Mean (± SEM) protective response in tissue for the indicated time postchallenge (CFU)b
|
|||
|---|---|---|---|---|
| Lung
|
Spleen
|
|||
| 4 wk | 12 wk | 4 wk | 12 wk | |
| Erdman | 1.26 ± 0.13 | 0.49 ± 0.03 | 1.27 ± 0.40 | 0.71 ± 0.17 |
| C913 | 0.87 ± 0.20 | 0.57 ± 0.10 | 0.81 ± 0.10 | 0.89 ± 0.20 |
| CDC1551 | 1.02 + 0.21 | 0.62 ± 0.15 | 1.32 ± 0.08 | 0.74 ± 0.20 |
| ChS | 0.75 ± 0.27 | 0.82 ± 0.02d | 0.55 ± 0.04 | 0.58 ± 0.25 |
| HN878 | 1.25 ± 0.11 | 0.40 ± 0.11c | 0.84 ± 0.26 | 0.35 ± 0.02e |
| N4 | 0.92 ± 0.12 | 0.37 ± 0.05c | 0.77 ± 0.25 | 0.14 ± 0.05e |
| NHN5 | 1.11 ± 0.13 | 0.95 ± 0.10d | 0.48 ± 0.10 | 0.33 ± 0.12e |
| NY669 | 1.15 + 0.42 | 0.34 ± 0.25c | 0.93 ± 0.02 | 0.63 ± 0.14 |
| NY920 | 1.11 ± 0.22 | 0.80 ± 0.19 | 0.75 ± 0.02 | 0.68 ± 0.20 |
In this study, the ChS, HN878, N4, and NHN5 isolates are Beijing-lineage strains.
Mean protection is the average protective response (number of CFU in naïve mice − number of CFU in vaccinated mice) for two to three experiments.
All of the BCG-induced protective responses in the lung at 4 and 12 weeks postchallenge were significant relative to the naïve controls except for the 12-week protection against the HN878, N4, and NY669 infections.
Immunization with BCG induced significantly better protection against the ChS and NHN5 infections than against the Erdman challenge at 12 weeks post-challenge.
All of the BCG-induced protective responses in the spleen at 4 and 12 weeks post-challenge were significant relative to the naïve controls except for the 12 week protection against the HN878, N4 and NHN5 infections.