内置式佐剂LTB对空肠弯曲菌重组蛋白疫苗免疫增强作用的研究

RESEARCH ON THE IMMUNOLOGIC ENHANCEMENT OF RECOMBINANT PROTEIN VACCINE FROM PEB1-LTB CONSTRUCTION MODEL

目的构建空肠弯曲菌(CJ)外膜蛋白(PEB1)及大肠埃希菌LTB融合疫苗并研究其免疫原性。方法应用重组PCR技术将PEB1和LTB序列连接,构建PEB1-LTB融合基因,将其克隆入原核表达载体pET-28a,转化入大肠埃希菌BL21,SDS-PAGE电泳表达,Western印迹检测表达蛋白的抗原性。肌注方式免疫小鼠,末次免疫2周后,测定小鼠血清中IgG、IgA及黏膜冲洗液中sIgA抗体水平。结果 PCR扩增分别获得约787、372bp产物,二者融合后获得一约1180bp目的基因;该重组蛋白可具有良好的免疫原性,肌注小鼠后其血清IgG、IgA及黏膜冲洗液中sIgA含量均显著增高(P<0.01)。结论构建PEB1-LTB融合蛋白可有效增强小鼠免疫应答水平。

Objective To construct a fusion vaccine of C jejuni PEB1 protein and Escherichia coli heat-labile enterotoxin B（LTB）,i.e.PEB1-LTB,and to study the immunogenicity of the fusion vaccine.Methods The PEB1 and LTB were amplified by recombinant PCR to construct a fusion gene.The fusion gene was subcloned into a procaryon expression vector PET-28a and was then transformed into E.coli BL21.SDS-PAGE electrophoretic expressions were got.The antigenicity of the recombinant fusion protein was analyzed by Western blotting.Two weeks after the final immunization of mice through intramuscular injections,the antibodies and cytokines were detected,including the specific IgG and IgA antibodies in serum,sIgA in mucosa douche.Results The PCR fragments of PEB1,LTB and PEB-LTB were about 787,372bp and 1180bp respectively.The recombinant protein had good immunogenicity.The levels of IgG,IgA and sIgA antibodies were all higher than those in other groups（P0.01）.Conclusion The construction of the fusion protein of PEB1-LTB in E.coli cells can effectively enhance the immune response of mice.