表达EB病毒主要膜蛋白的非复制型重组痘苗病毒毒力及体液免疫反应

Virulence and humoral immune response of non-replicating vaccinia recombinant virus expressing the major envelope antigen GP350/220 of EBV

利用表达EBVGP35 0 / 2 2 0的非复制型重组痘苗病毒VMAΔCK及复制性重组痘苗病毒VMA ,注射乳鼠脑内 ,观察毒力。同时 ,用VMAΔCK及VMA免疫Balb/c小鼠 ,经ELISA测定其特异性抗体水平。免疫血清用抗体中和EBV感染Raji细胞抑制产生早期抗原 (NEA)法测定其中和抗体滴度。将免疫血清与P3HR 1细胞共同孵育后 ,测上清中EBV滴度以观察抗体抑制EBV从P3HR 1细胞中释放效应。结果发现 ,VMAΔCK毒力明显低于VMA ,其LD50为 4.5 0PFU/ 0 .0 2ml,而VMAΔCK的LD50 大于 10 6PFU/ 0 .0 2ml。VMAΔCK与VMA免疫血清中抗GP35 0 / 2 2 0抗体水平无明显差异 ,而初免后抗痘苗病毒抗体水平VMA免疫组较VMAΔCK免疫组高 5倍左右。VMAΔCK及VMA免疫组血清中和抗体水平没有明显差异。VMAΔCK免疫血清稀释度与P3HR

The non?replicating vaccinia recombinant virus VMAΔCK and the replicating virus VMA which all expressing the major envelope antigen(MA) GP350/220 of EBV were inoculated in the brains of the newborn mice to evaluate the virulence of them. On the other hand, the Bal b/c mice were immunized by VMAΔCK and VMA, and the sera antibodies levels were assayed by ELISA. The EBV?neutralization antibodies levels in sera were assayed by the techniques based on the neutralization of early antigens (EA) synthesis in Raji cells. P3HR?1 cells were cultured with various dilution of each of sera and the EA?inducing titers of P3HR?1 EBV in culture supernatants were detected to evaluate the activity of the antibodies in sera inhibition of P3HR?1 EBV release.The results confirmed that the virulence of VMAΔCK whose LD 50 was 4.50 PFU/0.02 ml was weaker than that of VMA, whose LD 50 was higher than 1×10 6 PFU/0.02 ml. The levels of anti?vaccinia virus antibodies between two groups of mice after first immunization showed the prominent differences, but the levels anti?GP350/220 antibodies between them were not. The titers of EBV?neutralization antibodies did not show remarkable differences, too. The dilution of sera of the mice immunized by VMAΔCK demonstrated dose dependent relation with titers of EBV in supernatants of P3HR?1 cells cultures.