牛源金黄色葡萄球菌黏附素纤连结合蛋白A分泌型DNA疫苗诱导小鼠免疫效应的研究

Study on the Immungenicity of Bovine Staphylococcus aureus Fibronectin-binding Protein A (FnbpA) Secretory DNA Vaccine in Mice

采用PCR方法对编码金黄色葡萄球菌黏附素纤连结合蛋白A(FnbpA)的A区基因片段进行了特异性扩增,构建了真核表达载体pVAX-SFn,转染BHK-21细胞后经ELISA可检测出分泌表达的FnbpA蛋白。将真核重组表达质粒肌肉注射C57BL/6小鼠,免疫后检测小鼠血清抗体效价、淋巴细胞增殖及对试验小鼠攻毒试验。结果表明,该重组表达载体诱导细胞和体液免疫应答的强度均明显超过对照组。对小鼠的攻毒试验结果提示该重组DNA经肌肉注射途径接种可对小鼠产生免疫保护。本试验的结果对该DNA疫苗今后在实际中的应用奠定了良好的试验基础。

Region A of fibronectin-binding protein A （FnbpA） was amplified by PCR and the recombinant expression vector pVAX-SFn was constructed. Expressed protein was analyzed and identified by Western blotting and ELISA. Then the recombi nant plasmid was used to immune C57BL/6 mice and induced antibody, T lymphocyte proliferative response and experiment mice challenge test were measured. The results showed that cellular and humoral immune responses induced by recombinant plamid were much stronger than the control one. The challenge experiment in immunized C57BL/6 mice indicated that the re combinant eukaryotic plasmid based on FnbpA could induce immune response effectively in mice. This result built a good foun- dation for oractical use of this DNA vaccine in future.