重组登革病毒E蛋白结构域Ⅲ抑制登革病毒感染的初步研究

Recombinant envelope glycoprotein domain Ⅲ of dengue virus inhibit virus infection

目的 了解原核表达的登革病毒（dengue virus，DV）的E蛋白结构域Ⅲ直接抑制登革病毒感染及其抗体的中和作用。方法 在大肠埃希菌中表达l～4型登革病毒E蛋白结构域Ⅲ（EⅢ）。重组蛋白纯化后，进行阻断DV．2感染BHK-21细胞试验。用重组蛋白制备免疫血清，检测抗体中和作用。结果 在大肠埃希菌中成功表达了1～4型登革病毒E蛋白结构域埃希菌，4型重组E蛋白结构域Ⅲ均能够阻断2型DV感染，4型重组蛋白的免疫血清均能中和2型DV，但中和抗体效价不同。结论 原核表达的登革病毒结构域Ⅲ可以直接抑制病毒感染，所产生的抗体具有中和作用。直接抑制和中和抗体均对同型病毒作用较强。

Objective To observe the ability of dengue virus recombinant envelope protein domain expressed in E. coli to inhibit virus infection and induce the neutralizing antibody. Methods E m protein of Dengue virus serotypes 1-4 were expressed in E. coli BI21（DE3） then purified. Recombinant proteins were tested to inhibit DV2 from infecting BHK-21 cell. Rabbits were immunized with recombinant proteins to produce anti-E Ⅲ serum, Antibody titers were determined by neutralizing assay. Results The recombinant E Ⅲ proteins of Dengue virus serotypes 1-4 were expressed in E. coli. They effectively protected BHK cells in culture against DV2 infection, All four type anti-EⅢ sera can neutralize DV2 but their efficacies are different. Conclusion EⅢ proteins of dengue virus expressed in E. coli can directly inhibit DV2 infection. Neutralizing antibodies were induced by EⅢ proteins. Both E Ⅲ protein of dengue virus and the neutralizing antibodies they induced are more efficient in inhibiting homologous dengue serotypes infection than heterologous serotypes.