中文摘要：

目的：制备抗阿尔茨海默病的重组蛋白疫苗。方法：将β淀粉样蛋白42肽N端表位Aβ1-15基因，通过来源于破伤风毒素的辅助性T细胞表位多肽TTP基因片段，与大肠杆菌L-门冬酰胺酶Ⅱ（AnsB）基因的C末端融合，构建表达质粒pET28a—AnsB-TTP-Aβ1-15。转化至E．coli BL-21，TBYE培养基（Kan＇）培养，乳糖诱导表达，通过渗透休克、DEAE52-cellulose和Sephadex G-100柱层析制备融合蛋白rAnsB-TTP-Aβ1-15通过酶活力和抗原性测定鉴定融合蛋白。结果：获得的融合蛋白rAnsB-1TTP—Aβ1-15保留了AnsB71％的催化活力，具有与抗Aβ1-42抗体特异性结合的能力。结论：获得了在AnsB多聚酶分子表面呈现有Aβ1-15，表位的融合蛋白rAnsB-TTP—Aβ1-15为抗阿尔茨海默病疫苗研究奠定了基础。

英文摘要：

Objective To develop a novel recombinant vaccine against Alzheimer＇s disease. Methods The expression plasmid of pET28a-AnsB-TTP-A1-15 encoding a fusion protein composed of L-asparaginase B, a tetanus toxin peptide （TTP） spacer （831 -854 fragment）, and the B cell epitope （Aβ1-15） of Aβ1-42 peptide was constructed. It was transformed into E. coli and the fusion protein of rAnsB-TTP-Aβ1-15 was expressed and targeted to the periplasm of bacteria after inducing by lactose. The periplasm fusion protein was extracted by osmic shock and furthermore purified by DEAE52-cellulose and Sephadex G-100. This purified fusion protein will be detected with asparaginase activity and ELISA assay. Result The purified rAnsB-TTP-Aβ1-15 didn＇t only exhibit approximately 71% activity of the native enzyme, but also could bind to anti-Aβ1- 42 antibody. Conclusion The study showed that the fused B cell epitope of Aβ1-42 could be displayed on the surface of rAnsB-TTP-Aβ1-15 , which is hope for develop to a future vaccine against Alzheimer＇s disease.