摘要:目的 研究弓形虫核酸疫苗，以用于弓形虫病的防治。 方法 根据ROP2基因序列，设计合成能表达ROP2完整蛋白基因的扩增引物，扩增ROP2靶基因并克隆于PUCm-T载体，然后再亚克隆于真核表达载体pc-DNA3质粒中，制备弓形虫pc-DNA3-ROP2核酸疫苗;应用裸pc-DNA3-ROP2免疫小鼠，通过免疫学指标的检测，评价小鼠的免疫应答反应，最后应用弓形虫RH株攻击实验，评价出该疫苗的有效保护率、安全性和在人类及畜类的应用价值。 结果 以ROP2基因为模板，PCR扩增出1.7kb DNA条带，与预想结果一致;将扩增DNA回收并成功的克隆了ROP2(PUCm-T-ROP2)，然后亚克隆并构建了pc-DNA-ROP2重组体，通过酶切、PCR扩增和基因测序证明亚克隆的重组子正确，ROP2扩增基因包含了ROP2蛋白基因读码框内的完整序列;在应用疫苗免疫接种小鼠结果显示，疫苗接种能使小鼠产生强烈的细胞、体液免疫反应;攻击实验结果显示，实验组小鼠的存活时间明显延长，并且开始死亡时间明显延迟(P<0.001)，实验组9只小鼠中有1只长期存活;在实验的整个过程中，没有发现小鼠对免疫接种的毒性和异常反应。 结论 该疫苗免疫原作用强，具有很好的开发应用价值，目前可在动物群体中试验应用。

    关键词:弓形虫;ROP2基因重组;核酸疫苗;免疫保护作用

    Studies on ROP2gene/vaccine for control of toxoplasma infection.

    HAN Guang-dong，WEI Qing-kuan，ZHANG Dian-bo，et al.

    (Molecular Department of Shandong Provincial Institute of Parasitic Diseases，Jining272033，Shandong，P.R.China)

    ABSTRACT:Objective To carry out study on nucleic acid vaccine for control of toxoplasmosis in human and animals. Method Primers were designed and synthesized and ROP2gene was amplified，then cloned into plasmid PUCm-T，again recom-bined into an eukaryotic expression vector of pc-DNA3and named pc-DNA3-ROP2;The insert was identified by enzyme diges-tion、PCR amplification、sequence analysis and the naked pc-DNA-ROP2as a vaccine was inoculated into mice;blood was collect-ed one day before and2weeks after each inoculation;4mice in each group were killed to get lymph notes for lymphocyte phenotype analysis and cytokines detection14days after third immunization;challenge experiment with Toxoplasma gondii RH strain was con-ducted;the protective effect and safety of DNA vaccine ......