幽门螺杆菌粘附素AlpA基因克隆、表达及免疫原性研究

目的 构建表达幽门螺杆菌(Hp)黏附素AlpA的候选菌株并研究其免疫原性。方法 利用PCR技术扩增粘附素AlpA基因，将其定向插入pET-22b( )载体，在BL21(DE3)大肠杆菌中表达并通过免疫印迹实验研究其免疫原性。结果 克隆的粘附素AlpA基因序列与基因库公布的基本一致，粘附素AlpA重组蛋白表达量占菌体总蛋白的31．9％，经免疫印迹证实该重组蛋白可被AlpA免疫兔血清和Hp,感染患者血清所识别。结论．AlpA克隆、高效表达及其免疫原性的初步证实，为Hp基因工程疫苗的研制和粘附机制的研究打下了基础。

Study on the cloning and expression and the immunogenicity of Helicobacter pylori adhesin AlpA gene

Objective To construct a recombinant strain which expresses adhesin AlpA of Helicobacter pylori(H.pylori) and to study the immunogenicity of adhesin AlpA. Methods The adhesin AlpA DNA was amplified by PCR and inserted into the prokaryotie expression vector pET-22b(+)and expressed in the BL21(DE3) E.coli strain. Adhesin AlpA immunogenicity was studied by Western blot test. Results DNA sequence analysis showed that the sequence of adhesin AlpA DNA was almost the same as that of the published by GenBank. The adhesin AlpA recombinant protein accounted for 31.9% of the total bacterial protein. Western blot analysis of rAlpA confirmed that it could be specially recognized by serum from rabbit immunized with AlpA itself and H.pylori infected patients. Conclusion Cloning and high-expression of adhesin AlpA and primary confirmation of its immunogenicity lay the foundation for H.pylori gene engineering vaccine preparation and adhering mechanism research.