本实验从活化扁桃体细胞中克隆出人IL21的cDNA并进行序列测定，同时构建了中国人IL21表达克隆，并在DH5α宿主菌中表达出与谷胱甘肽转移酶融合的蛋白。采用琼脂糖珠结合的纯化方法，获得了与理论值相符合的纯化条带。在进一步的Western Blotting分析中显示，该种条件下表达的融合蛋白能与IL2的单抗产生结合反应。这一实验结果结合人IL21最新的结构分析和体外活性实验，进一步证实了人IL21在临床与IL2联用或单独使用具有的调节免疫功能和抗肿瘤活性[2,7]，并为进一步检测人IL21的各种体内外活性奠定了理论和实验的基础。
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