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利用ＰＣＲ－Ｃｌｏｎｉｎｇ技术和ＤＮＡ重组技术，构建了两类ＩＬ－２－ＰＥ４０＇嵌合基因的表达载体，分别由ＩＰＴＧ和温度（４２℃）诱导表达。在对表达产物进行了酶切位点和片段大小、电泳迁移率、分子量的初步鉴定后，又对融合蛋白的白细胞介素２（ＩＬ－２）和ＰＥ４０＇组分的抗原性进行了ＥＬＩＳＡ鉴定。从菌体蛋白中初步分离纯化了重组毒素，并测定其对细胞表面表达ＩＬ－２受体的活化Ｔ淋巴细胞的靶向杀伤效应及对混合淋巴细胞反应的抑制作用。结果表明，ＩＬ－２－ＰＥ４０＇融合蛋白确实对ＩＬ－２Ｒ＋细胞具有明显的靶向杀伤效应并呈剂量依赖关系，与对照组相比，随着保温时间的延长（６、２４、４８ｈ），杀伤效应趋于增强（Ｐ＜０．０５）。混合淋巴细胞培养结果显示，该融合蛋白对单相和双相反应均有不同程度的免疫抑制作用（Ｐ＜０．０１）。
Two types of IL-2-PE40 ’chimeric gene expression vectors were constructed by PCR-Cloning technology and DNA recombination technology, respectively, induced by IPTG and temperature (42 ℃). The expressed products were identified by enzyme digestion, fragment size, electrophoretic mobility and molecular weight. The antigenicity of IL-2 and PE40’of the fusion protein was identified by ELISA . The recombinant toxin was initially isolated and purified from the bacterial protein, and its killing effect on activated T lymphocytes expressing IL-2 receptor on cell surface and its inhibitory effect on mixed lymphocyte reaction were determined. The results showed that the IL-2-PE40 ’fusion protein did have a significant targeted killing effect on IL-2R + cells in a dose-dependent manner. Compared with the control group, IL- The killing effect tends to increase (P <0.05). The result of mixed lymphocyte culture showed that the fusion protein had different degree of immunosuppression on monophase and biphasic responses (P <0.01).