中文摘要：

目的制备异源性T辅助细胞表位修饰的人可溶性肿瘤坏死因子家族的B细胞激活因子（BAFF）突变体，并对其免疫抑制功能进行分析。方法经原核表达和Ni-NTA层析纯化制备异源性T辅助细胞表位修饰的人可溶性BAFF突变体；用所制备的重组蛋白免疫BALB／c小鼠，酶联免疫吸附试验（ELISA）检测小鼠血清中抗人BAFF抗体的滴度；四甲基偶氮唑蓝（MTTl）实验检测免疫小鼠血清抑制重组sBAFF和天然sBAFF功能的情况。结果重组蛋白在大肠杆菌中均获得了高效表达；经Ni-NTA层析纯化后，目的蛋白的纯度均达90％以上；用重组蛋白免疫小鼠均可诱导产生高滴度抗人可溶性BAFF抗体：免疫小鼠血清可抑制重组sBAFF和天然sBAFF刺激淋巴细胞增殖的功能。结论成功制备了可诱导产生高滴度特异性抗体的BAFF免疫抑制分子，为进一步探讨其治疗作用奠定了基础。

英文摘要：

Objective To prepare T-helper cell （Th） epitope-modified human soluble B cell activating factor belonging to the tumor necrosis factor family （BAFF） mutants and evaluate their immune response in vaccinated mice. Methods Recombinant cDNAs were cloned and ligated into the prokaryotic expression vector pQE-80L respectively. The recombinant proteins were induced to express by IPTG in E.coli DH5α and purified with Ni-NTA chromatography. BALB/c mice were immunized with recombinant proteins respectively and the titres of the antibodies that were cross-reactive with BAFF in sera were analyzed by ELISA. Inhibiting ability of the antibodies in sera was analyzed by MTT assay. Results The recombinant proteins were highly expressed in E.coli DH5α. After purification, the purity of recombinant proteins was more than 90%. BALB/c mice immunized with recombinant proteins produced high levels of BAFF-specific antibodies. Cell proliferation assay showed that the sera of immunized mice could inhibit the proliferation-inducing activity of recombinant sBAFF and natural sBAFF. Conclusion The immune inhibitors of human BAFF which can induce polyclonal antibodies that are cross-reactive with BAFF are successfully prepared. These results may provide the basis for further study of their therapeutic effects.