Abstract:Objective:To evaluate the immunity effect of H1N1 influenza vaccine prepared by film-dispersion and freeze-thawing method,and to provide expermental foundation for attenuated live vaccine liposome preparation. Methods:Experimental mice were divided into the influenza vaccine non-liposome group,the film-dispersion prepared H1N1 influenza vaccine liposome group,the freeze-thawing lyophilized prepared H1N1 influenza vaccine liposome group,the positive control group and the negative control group (n=5). 4 μg and 6 μg hemagglutinin of H1N1 subtype per mouse were tracheally delivered to the mice for the non-liposome group and the lyophilized liposome groups,with the same dose intraperitoneally delivered groups as the positive control,and the PBS intraperotoneal injection group as the negative control. After 7,14 and 28 d of immunization,serum levels of HA antibodies were measured by the hemagglutination-inhibition method,and serum cytokine levels were measured by the ELISA method. Results:By pulmonary injection of the two liposome groups,the antibody titers of 6 μg dose groups were higher than those of 4 μg dose groups (P < 0.05). HA antibody titers of the two pulmonarily delivered liposome groups were higher than those of the pulmonarily (P < 0.05) and intraperitoneally (P < 0.01) injected non-liposome group. Antibody titers of the film-dispersion liposome group for both doses were higher than those of the freeze-thawing lyophilized liposome group. IL-2 and IFN--酌 produced by the pulmonary injected liposome groups were higher than those of the intraperitoneally delivered non-liposome group. Conclusion:The humeral and cellular immunities could be effectively induced by pulmonarily delivered vaccine liposomes;The film-dispersion method group is better than the freeze-thawing lyophilized group in terms of immunity strength. For the freeze-thawing lyophilized prepared H1N1 influenza vaccine liposome group,the immune response occurs at 14 d after vaccination,while the titer ratio is only 1.8 for normal vaccinated flu vaccine. The freeze-thawing lyophilized liposome vaccine also stimulates higher levels of cytokines.