| |
Lung virus titerb
(log10 TCID50/ml)
|
Survival rate
(No. of survivors/no. tested)
|
---|
Plasmid DNA
|
Dose
(μg)
|
3 days
|
5 days
|
7 days
|
3 days
|
5 days
|
7 days
|
---|
HA
DNA
|
10
|
6.25 ± 0.35
|
4.80 ± 0.28c
|
4.25 ± 0.35c
|
0/12
|
0/12
|
6/12
|
|
50
|
5.75 ± 0.35
|
4.55 ± 0.07c
|
4.00 ± 0.70c
|
0/12
|
4/12
|
10/12d
|
|
100
|
5.75 ± 0.35
|
4.55 ± 0.07c
|
3.25 ± 0.35c
|
0/12
|
6/12
|
12/12d
|
Control
|
6.25 ± 0.35
|
0/12
|
-
a Mice were immunized once with HA DNA 3, 5 and 7 days, respectively, before the challenge and at various dosages. Then all the mice were challenged under anesthesia with 5 LD50 of homologous A/Chicken/Henan/12/2004(H5N1) virus. Three days after the viral challenge, the mice were sacrificed. The trachea and lungs were taken out and washed twice by injecting 2 ml of PBS containing 0.1% BSA. The bronchoalveolar wash was used for virus titration after removing cellular debris by centrifugation. The survival of mice 3 weeks after the challenge was measured.
-
bValues represent means ± SD of 4 mice from each group.
-
c Significantly different from the control groups (p < 0.05) by ANOVA.
-
d Significantly different from the control groups (p < 0.05) by Fisher's exact test.