以减毒猪霍乱沙门菌为载体的抗O型口蹄疫病毒重组活菌苗在家兔体内免疫应答的初步研究

Preliminary Study on the Recombinant Live Vaccine against FMDV Type O Delivered by Attenuated Salmonella choleraesuis in Rabbits

将含有口蹄疫病毒疫苗基因的真核表达质粒pBO1经过中间宿主鼠伤寒沙门菌LB5010修饰后,电转化到减毒的猪霍乱沙门菌C500中,构建成抗O型口蹄疫病毒的重组活菌苗pBO1/S.cho.血清凝集实验验证,筛选到的转化菌仍然具有猪霍乱沙门菌的血清学特性,即具有免疫原性.采用口服方式免疫家兔,检测重组菌在家兔体内诱导的免疫应答.家兔免疫后8周,分离脾脏T细胞,检测T细胞增殖情况.结果显示,口服pBO1/S.cho的家兔T细胞在FMDV特异性抗原的刺激下有明显的增殖反应,刺激指数SI>11;免疫后2周和8周分别取家兔静脉血,用液相阻断ELISA法检测血清中针对FMDV的特异性抗体,pBO1/S.cho组家兔产生的抗体效价为1/32.

Recombinant strains of Salmonella choleraesuis C500 which containing eukaryotic expression plasmid pBO1 was constructed. These plasmids contained the immunodominant epitope of foot-and-mouth disease virus. Evaluation of specific immune response was performed in rabbits by oral immunization with the live recombinant pBO1/S, cho. Results showed that T cell response and specific antibodies were elicited. This approach may present a general strategy for eliciting immune responses against DNA vaccine in live bacterial vaccines. The stimulate index of T cell of Rabbits, stimulated by specific antigen of FMDV, can reach to 11.0 and the titer of antibody of 1/32 was received by detecting serum with liquid block ELISA.