Table 3.
Mucosal Vaccination With Vectors Expressing LAS NP Cross-protects Mice From Lethal LCMV Challenge
| Immunization*† | No. of Survivors/Total (% Survivors) | 95% CI‡ | |
|---|---|---|---|
| Ctrl.Salm. | 0/10 | (0%) | 0–31% |
| Salm-LasNP | 5/14 | (37%) | 25–49% |
| Mock | 0/10 | (0%) | 0–31% |
| VV-WT | 0/20 | (0%) | 0–18% |
| VV-LASNP | 4/12 | (33%) | 24–42% |
| VV-LCMNP | 20/20 | (100%) | 82–100% |
BALB/c mice were inoculated by intragastric intubation with 5 × 109 bacteria either Ctrl.Salm. (DS116) or Salm-LasNP (DS228), or with 1 × 106 PFU of VV-recombinant, and boosted with the same recombinant vector 21 days after the primary inoculation. “Mock” indicates that mice were inoculated intragastrically with only bicarbonate solution.
Mice were challenged i.c. with 2 × 102 to 103 PFU of LCMV Armstrong at day 24, and mortality was recorded for 15 days.
The method used to determine the 95% confidence interval (95% CI) was the exact two-sided test. Because of CI overlaps, there is no significant difference between the 37% survival of the Salmonella vaccinees and the 33% survival of the vaccinia vaccinees. In contrast, there is significant difference between the control (VV-WT, 0% survival) and the vaccinees given LAS NP constructs (33–37% survival). There is also a significant difference between the VV-LCMNP vaccinees with 100% survival and the VV-LASNP vaccinees with 33% survival.