西方马脑炎病毒E2蛋白的免疫原性研究

Immunogenicity evaluation of the prokaryotic expressed E2 protein of western equine encephalomyelitis virus in mice

为研究西方马脑炎病毒(WEEV)囊膜E2蛋白的免疫原性,本研究通过诱导重组菌pET30-E2/E.coliBL21表达E2蛋白,将纯化的重组蛋白与弗氏佐剂乳化制备免疫原免疫小鼠,免疫剂量为50μg/只。二免后实验组小鼠体内CD4+/CD8+T细胞比例为3.38±0.19,细胞因子IL-2、IL-4及IFN-γ浓度分别为195.7±14.5 pg/mL、248.2±16.2 pg/mL与315.8±13.3 pg/mL;三免后实验组小鼠淋巴细胞增殖指数(PI)检测结果显示:ConA刺激组为2.18±0.17,E2蛋白刺激组为1.56±0.15;其特异性抗体IgG效价为1∶640。以上实验组各项免疫指标均与对照组呈显著差异(p<0.05),表明E2蛋白能够刺激小鼠产生较强免疫反应,具有较强免疫原性。本研究为WEEV基因工程亚单位疫苗研制奠定了良好基础。

In order to evaluate the immunogenicity of western equine encephalomyelitis virus （WEEV） E2 protein, the recombinant E2 protein was expressed in E.coli and purified according to His-bind protein purification kit. The BALB/c mouse was immunized with 50 μg E2 protein formulated with Freund＇s adjuvant. The detection results showed that the ratio of CD4＋/CDS＋T cell in immunized groups was 3.38±0.19, and the concentration of IL-2, IL-4 and IFN-y was 195.7±14.5 pg/mL, 248.2±16.2 pg/mL, 315.8±13.3 pg/mL, respectively, post the secondary immunization. In addition, the proliferation index （PI） in immunized groups were 2.18±0.17 and 1.56±0.15 stimulated by ConA and E2 protein, respectively, and IgG antibody titers was 1：640 post the third immunization. Moreover, all the results above showed that the immune indices in immunized groups were significant difference compared with the control groups （p〈0.05）, which demonstrated that E2 protein was able to induce efficiently immune response in immunized mice.