TGEV和PEDV融合S蛋白在乳酸乳球菌食品级细胞内高效诱导表达与免疫原性分析

High efficient expression and immunogenicity analysis of TGEV and PEDV fusion S protein in food-grade Lactococcus lactis intracellular

本研究以乳酸乳球菌食品级细胞内高效诱导表达载体pRNA48为基础,构建了含猪传染性胃肠炎病毒(TGEV)和猪流行性腹泻病毒(PEDV)融合S基因的表达质粒pRNA48-TPs和重组菌L.lactis NZ9000/pRNA48-TPs。SDS-PAGE分析nisin诱导后重组菌表达的细胞内目的蛋白,然后分别对兔子进行注射免疫和口服免疫,并用Western Blot进行免疫原性分析,结果表明,重组菌细胞内表达的TPs融合蛋白具有较好的免疫原性,注射免疫产生的抗体能特异性识别胞内TPs融合蛋白,同时发现口服免疫也能产生特异的抗体血清,初步证明重组蛋白具有黏膜免疫原性。

Firstly, the fusion gene S of TGEV （Swine transmissible gastroenteritis virus） and PEDV （Porcine epidemic diarrhea virus） was successfully constructed and was cloned into the food-grade intracellular high efficient induced expres- sion vector pRNA48 of Lactococcus lactis NZ9000 to acquire the recombinant bacteria L.lactis NZ9000/pRNA48-TPs.Then the recombinant strain was induced by nisin and the SDS-PAGE was used to analyse the expression of the target protein af- ter the intracellular protein was extracted.And then rabbits were administrated by injection immunization and oral immu- nization respectively and then analyzed by western blot.The results showed that ：the TPs fusion protein expressed by L.lactis NZ9000/pRNA48-TPs intracellular had good immunogenicity.Antibodies generated by injection immunization could identify specific intracellular TPs fusion protein. Meanwhile, oral immunization could also generate specific serum antibodies.All of the results preliminary proved that the recombinant protein with mucosal immunogenicity.