流感DNA疫苗免疫BALB/c小鼠克服母源性抗体干扰的研究

目的 为了克服母源性抗体对子代的免疫抑制作用,寻找避免母源性抗体干扰的流感疫苗免疫策略.方法 以小鼠为动物模型,接种流感灭活疫苗或DNA疫苗,并用致死量流感病毒感染.感染后检测小鼠的存活率、肺部病毒滴度、体内抗体滴度等指标,对疫苗的保护效果进行评价.结果 母代与子代免疫相同的疫苗,不论是灭活疫苗还是DNA疫苗,子代体内的母源性抗体都抑制了子代免疫后的自动免疫应答,表现为子鼠接种疫苗后不能抵御致死量流感病毒感染;母代免疫流感灭活疫苗,子代免疫神经氨酸酶DNA疫苗,子鼠能够克服母源性抗体干扰,抵御致死量流感病毒感染;母代和子代免疫不同的DNA疫苗,即母代免疫血凝素或神经氨酸酶DNA疫苗,子代免疫神经氨酸酶或血凝素DNA疫苗,也能达到克服母源性抗体干扰的目的 .结论 流感DNA疫苗免疫BALB/c小鼠能克服母源性抗体的干扰,这为临床新生儿抗母源性抗体干扰的研究提供了实验参考.

Immunization of BALB/c mice with influenza DNA vaccine can overcome the interference of maternal antibody

Objective To find an effective way of offspring immunization with influenza vaccines in presence of maternal antibody.Methods Either influenza inactivated or DNA vaccines were used to immunize mice with various immunization strategies.After immunization,mice were challenged with a lethal dose of homologous virus.The efficacy of immunization was evaluated by measuring the survival rates,lung virus titers and antibody titers of the mice.Results When the offspring were immunized with the same vaccines as those for their mothers,whether inactivated or DNA vaccines,the active immune responses in offspring were inhibited by the presence of maternal antibody.However,the interference could be overcome under the following situations:immunization of offspring with neuraminidase DNA vaccine and immunization of their mothers with inactivated vaccines,or immunization of offspring with different DNA vaccines(hemagglutinin DNA or neuraminidase DNA)from those for their mothers.Conclusion Immunization of BALB/c mice with influenza DNA vaccine can avoid the interference of maternal antibody.The results provide an experimental basis for study on overcoming the immunosuppression caused by maternal antibody in neonates.