Table 1. Protection against lethal PR8 virus challenge in mice by administrated intranasally with NP or TAT-NP vaccine.
| Group | Immunogen | Dose (μg) | Protection against challenge with PR8 virus | |
|---|---|---|---|---|
| Lung virus titers (Log10TCID50/mL) | Survival mice/tested mice | |||
| A | TAT-NP | 10 | 5.50 ± 0.17b | 3/10b |
| B | TAT-NP | 30 | 4.89 ± 0.38b | 7/10ab |
| C | TAT-NP | 100 | 3.50 ± 0.17ab | 10/10ab |
| D | NP | 30 | 5.44 ± 0.20b | 0/10 |
| E | NP | 100 | 4.78 ± 0.48b | 4/10b |
| F | PBS | − | 6.78 ± 0.51 | 0/10 |
Note: BABL/c mice were randomly divided into six groups. Mice were immunized intranasally with NP or TAT-NP vaccine, whereas control animals received PBS. Two weeks after the last immunization, mice were challenged with a lethal dose (10 × LD50) of influenza PR8 virus. BALF of three mice per group was collected 3 days after the challenge. Virus titers in the lungs as determined by plaque assay. Results are expressed as mean ± SD of three tested mice in each group. Survival rate of mice (n = 10) was monitored for 21 days. The t-test was used to determine difference in viral load. The survival rates were evaluated by log-rank (Mantel–Cox) test.
aDisplays statistically significant difference compared with the same dose NP group (P < 0.05).
bDisplays statistically significant difference compared with the PBS group (P < 0.05).