Optimization of vaccination regimens

To study the effects of different immunization intervals on the immune response of the JY-adjuvanted nasal spray H7N9 vaccine, we immunized mice at 7-day, 14-day, and 21-day intervals. Three groups of mice were anesthetized with 0.5 ml of 0.25% pentobarbital sodium by intraperitoneal injection and then intranasally immunized with the JY-adjuvanted nasal spray H7N9 vaccine with 4.5 μg HA. The control group was intranasally immunized with NS at days 0 and 14. Serum and BALF were collected 21 days after the second immunization. The titers of serum HI, anti-HA IgG, and BALF sIgA were detected.

To study the effects of different dosages on the immune response to the JY-adjuvanted nasal spray H7N9 vaccine, we immunized mice with different doses of HA: 15, 9, 4.5, 2.25, or 1.13 μg. Six groups of mice were used. Groups 1, 2, 3, 4, and 5 were immunized twice at days 0 and 21 (3-week interval) with different doses, and group 6 was immunized with NS as the control group. Serum and BALF were collected 21 days after the second immunization. The titers of serum HI, anti-HA IgG, and sIgA in BALF were detected.