中文摘要：

本研究对布鲁氏菌分泌蛋白 BMEI0339 进行了表达纯化、免疫反应性分析，并研究了该蛋白对胚胎滋养层细胞（HPT-8）的细胞因子表达的影响。首先从羊种布鲁氏菌（B.melitensis）标准株 16M 的基因组中克隆 BMEI0339 基因片段，亚克隆至融合表达载体 pET-28a，构建表达重组质粒 pET-28a-BMEI0339，并利用大肠杆菌进行表达。Westernblotting 方法检测其 免疫学 特 性 ；用 纯化的重组蛋白 感染 细胞，并 检测 IL-1、IL-10 和 TNF-α 表达 量。结果显示：成功构建了 pET-28a-BMEI0339 原核表达载体，并在大肠杆菌中成功表达了 BMEI0339 蛋白，Western blotting 检测其具有免疫反应性，该蛋白作用细胞后发现 TNF-α 的表达量低于 BSA 对照组，差异极显著（P＜0.01）；IL-1 和 IL-10 的表达量差异不显著（ P＞0.05）。本研究成功表达了布鲁氏菌分泌蛋白 BMEI0339，证实其具有一定的免疫原性，表明该蛋白影响了胚胎滋养层细胞 TNF-α 的表达。本研究为研究布鲁氏菌感染宿主细胞的致病机理提供理论基础。

英文摘要：

In this paper,the Brucella type IV secretion system protein BMEI0339 gene was expressed,purified,and analyzed of immunoreactivity,and the effect of this protein on the expression of embryonic trophoblasts＇ cytokines was studied.The BMEI0339 gene was obtained from Brucella melitensis 16M genome,it was cloned to expression vector pET-28a to construct recombinant plasmids pET-28a-BMEIO339,and expressed in the E.coli BL21 （DE3）.The immunological characteristics were analyzed by Western blotting.The cells were infected by purified recombinant proteins,and the expression of IL-I,IL-IO and TNF-α was detected.The results showed that the recombinant plasmids pET-28a-BMEI0339 was constructed,and BMEI0339 protein was expressed in E.coli BL21 （DE3）.The result of Western blotting showed that BMEI0339 protein had immunological characteristics. After BMEI0339 recombinant protein acting on cells ,the expression of TNF-α was lower than that in the control group with BSA,and the difference was highly significant（P〈0.01）;there was no difference in the expressions of IL-1 and IL-10 （P〉 0.05）. The Brucella type IV Secretion System Protein BMEI0339 gene was successfully expressed in this experiment,and the immunogenicity has been confirmed.The protein can influence the expression of TNF-α in embryonic trophoblast cells,and the result will provide a theoretical basis for researching the pathogenesis of Brncella infecting the host cells.