Table 2. Serum and mucosal antibody responses in mice.

Group	Immunogen	Dose (μg)	Ab response (ELISA, 2n)
			Serum IgG (Day 14)	Serum IgG (Day 28)	Serum IgG (Day 42)	NAL IgA
A	TAT-NP	10	13.00 ± 1.00	18.33 ± 0.58	21.33 ± 0.58	5.33 ± 0.58
B	TAT-NP	30	14.30 ± 0.58a	19.33 ± 0.94	23.00 ± 0.00	6.00 ± 0.00a
C	TAT-NP	100	15.60 ± 1.52a	23.33 ± 0.67	25.67 ± 0.58	7.33 ± 0.58a
D	NP	30	11.33 ± 0.94	19.67 ± 0.83	22.33 ± 1.15	4.67 ± 0.58
E	NP	100	13.67 ± 0.83	22.67 ± 1.52	24.33 ± 0.58	6.33 ± 0.58
F	PBS	−	Undetected	Undetected	Undetected	Undetected

Note: BABL/c mice (female, 6–8 weeks old) randomly were divided to 6 groups. Mice were anesthetized, followed by immunized intranasally 3 times with 2 weeks interval containing different doses of NP or TAT-NP. The control group was received PBS. Blood samples of three mice in each group were collected on day 14, 28 and 42 to detected NP specific IgG. NAL of three mice were collected on day 42 to evaluate IgA. End-point ELISA titers were expressed as the reciprocal of the highest sample dilution that yielded an OD ≥ mean+2 × SD of control mouse serum. Results are expressed as mean ± SD of three tested mice in each group. The t-test was used to determine difference in antibody titers. ^a Displays statistically significant difference compared with the same dose NP group (P < 0.05).