分子佐剂C3d增强猪流感病毒HA-DNA疫苗免疫原性的研究  

C3d-induced immune enhancement of the swine influenza HA expressed by a DNA vaccine

作　　者：李国新[1] 郑宝亮[2] 金媛媛[3] 田志军[3] 周艳君[3] 童光志[4] 

机构地区：[1]东北农业大学动物医学学院,黑龙江哈尔滨150030 [2]郑州牧业工程高等专科学校生物工程系,河南郑州450011 [3]中国农业科学院哈尔滨兽医研究所兽医生物技术国家重点实验室/猪传染病研究室,黑龙江哈尔滨150001 [4]中国农业科学院上海兽医研究所,上海200232

出　　处：《中国预防兽医学报》2008年第10期814-820,共7页Chinese Journal of Preventive Veterinary Medicine

基　　金：国家863计划(2006AA10A204);国家973计划(2005CB523200)

摘　　要：为了探讨分子佐剂C3d对猪流感病毒HA-DNA疫苗免疫原性的影响,本研究构建了3种表达不同形式HA的重组质粒,分别为:表达分泌型HA的质粒p-sHA、表达全长HA的质粒p-tmHA和融合表达3拷贝鼠C3d与HA的质粒p-sHA/mC3d3。3种质粒与空载体pCAGGS分别免疫BALB/c小鼠后,采用ELISA和HI试验检测抗体水平。结果显示,免疫后第8周,p-sHA组与p-tmHA组的抗体水平没有明显差别,而p-sHA/mC3d3免疫组的抗体水平显著高于这两组,说明分子佐剂C3d增强了抗体应答水平。淋巴细胞增殖试验及细胞因子检测实验结果显示,免疫后第8周,p-tmHA诱导了更强的淋巴细胞增殖反应和更高水平的IFN-,而p-sHA/mC3d3诱导了更高水平的IL-4,说明HA表达形式的变化影响了免疫反应的类型,C3d与HA融合后通过诱导IL-4的产生而使免疫反应倾向于Th2型。总之,本研究证实3拷贝分子佐剂C3d与分泌型HA融合后显著提高了DNA疫苗诱导的抗体水平。这提示质粒p-sHA/mC3d3免疫可能对接种动物提供高水平的保护,有希望成为抗猪流感病毒的候选疫苗。To evaluate the effects of C3d on the immunogenicity of the swine influenza HA expressed by a DNA vaccine. Plasmid encoding secretive HA （p-sHA）, complete HA （p-tmHA） or secretive HA-C3d fusion prtein （p-sHA/mC3d3） were constructed from H3N2 subtype of swine influenza virus and administered to mice, respectively. The immune response was monitored by ELISA and hemagglutination inhibition （HI） assays, p-sHA/mC3d3 was shown to induce higher level of anti-HA antibodies compared to p-sHA or p-tmHA. Furthermore, C3d fusion increased Th2-biased immune response by inducing IL-4 production. The IL-4 level in splenocytes from mice received p-sHA/mC3d3 was three times higher than those vaccinated with p-sHA or p-tmHA. These results showed that the murine C3d gene fused to the truncated HA gene could significantly enhance antibody responses to hemagglutinin, and the plasmid DNA expressing sHA/mC3d3 fusion proteins may represent an effective candidate vaccine against swine influenza virus.

关 键 词：猪流感病毒 DNA疫苗 分子佐剂 C3D 

分 类 号：S852.659[农业科学—基础兽医学] S858.28[农业科学—兽医学]