戊型肝炎病毒嵌合基因疫苗的初步研究

目的　构建含戊型肝炎病毒 (HEV)开放读码框架 (ORF2 )和ORF3嵌合基因的重组质粒 ,并探讨其作为DNA疫苗的可能性。方法　利用PCR方法获得约 0 8kb的戊型肝炎ORF2片段和ORF3的完整片段 ,同时将 2段片段克隆到同一真核表达载体 pcDNA3中 ,构建出含有ORF2和ORF3嵌合基因的质粒 pcHEV2 3;该重组质粒作为DNA疫苗免疫BALB/c小鼠 ,观察其在小鼠体内诱发的体液免疫应答和细胞免疫应答。结果　质粒DpcHEV2 3免疫组小鼠特异性抗体水平明显高于对照组。T细胞增殖反应显著强于空质粒对照组 (P <0 0 5 ) ,与生理盐水对照组比较有显著性差异 (P <0 0 1)。结论　重组质粒 pcHEV2 3可诱发小鼠产生特异性体液和细胞免疫应答 ,可为戊型肝炎DNA疫苗的研制提供依据。

Preliminary research on hepatitis E virus chimeric DNA vaccine

Objective To construct a recombinant plasmid which contained fragments of HEV ORF2 and ORF3 chimeric gene,and then assess its feasibility for use as a DNA vaccine.Methods HEV ORF2 fragment and full-length ORF2 was amplified by PCR.The PCR products were inserted into an eucaryotic expression plasmid pcDNA 3 to form a recombinant plasmid named pcHEV23(DNA vaccine).BALB/c mice were immunized with DNA vaccine and the humoral and cellular immune responses of the mice were detected.Results The HEV DNA vaccine can induce specific anti-HEV IgG and T lymphocyte proliferation.The lymphocyte stimulation index(SI) in the group immunized with pcHEV23 was high than that in control group( P <0.01).Conclusion HEV DNA vaccine constructed by us can successfully induce both humoral and cellular immune response.Thus providing an experimental evidence for its use in control of HEV infection.