大鼠IgG Fc片段与金黄色葡萄球菌黏附素FnBPB-ClfA的融合表达及其免疫学特性  

Expression of a fusion protein Fc-FnBPB-ClfA of Staphylococcus aureus and its immunogenicity

作　　者：潘海婷 郝永清[1] 

机构地区：[1]内蒙古农业大学兽医学院微生物学与免疫学实验室,内蒙古呼和浩特010018

出　　处：《中国预防兽医学报》2015年第4期299-303,共5页Chinese Journal of Preventive Veterinary Medicine

基　　金：国家自然科学基金(31460664);农牧交错区生态型现代奶业生产模式研究与示范(2012BAD12B09-02)

摘　　要：为提高金黄色葡萄球菌(S.aureus)串联表达的黏附素重组蛋白(r Fn BPB-Clf A)的免疫效力,本研究将RT-PCR扩增的大鼠Ig G Fc段基因与本实验室已构建的S.aureus Fn BPB-Clf A基因串联,采用SOE-PCR进行扩增,制备Fc-Fn BPB-Clf A融合基因,并将其克隆于p ET-32a(+)载体中进行原核表达。将表达的重组蛋白(r Fc-Fn BPBClf A)经乳头管注射(200μg/只)免疫哺乳期Wistar大鼠,并于加强免疫2周后,以1×109 cfu S.aureus经乳头管攻毒。结果表明,在加强免疫7 d后,与r Fn BPB-Clf A免疫组相比,r Fc-Fn BPB-Clf A免疫组血清和乳清中的抗体水平明显增高,而且Ig G水平动态检测结果表明,其特异性抗体上升趋势明显高于r Fn BPB-Clf A免疫组。攻毒保护试验证明,r Fc-Fn BPB-Clf A和r Fn BPB-Clf A免疫组对S.aureus清除率均显著高于对照组(p<0.01)。本研究结果表明,r Fc-Fn BPB-Clf A对S.aureus乳房炎的免疫效果更佳,为进一步研制有效防治S.aureus乳房炎疫苗提供了实验依据。To improve the immunogenicity of the recombinant fusion adhesin protein of Staphylococcus aureus FnBPB-ClfA （rFnBPB-ClfA）, the R.rattus IgG Fc gene was fused to FnBPB-ClfA gene by SOE-PCR and cloned into pET-32a （＋） vector to express the recombinant protein of rFc-FnBPB-ClfA in E.coli. Then, the lactating rats were immunized via teat canal with rFnBPB-CIfA and rFc-FnBPB-ClfA, respectively, and challenged with S.aureus at 2 weeks post the boost vaccination. The results showed that the IgG titers in the serum and whey were dramatically higher in rat group immunized with rFc-FnBPB-ClfA than that in the rFnBPB-ClfA immunized group after the boosting. Moreover, the challenge test demonstrated that S.aureus colony counts of immunized group （rFc-FnBPB-ClfA） were lower than control group （p〈0.01） and rFnBPB-ClfA group, indicating the IgG Fc enhanced the immuno-ability of the rFnBPB-ClfA. This study provided the basis of further developing subunit vaccine against S.aureus mastitis.

关 键 词：金黄色葡萄球菌 大鼠IgG Fc基因 FnBPB-ClfA串联基因 

分 类 号：S852.61[农业科学—基础兽医学]