摘要
针对肿瘤坏死因子（ＴＮＦ）在肿瘤治疗剂量下产生的严重毒副作用及一些肿瘤细胞上白细胞介素－６（ＩＬ－６）受体明显增高的事实，根据ＴＮＦ结构与功能研究的最新信息，利用ＰＣＲ技术，对人ＴＮＦα基因进行了改造，并将其与人ＩＬ－６成熟肽编码区ｃＤＮＡ通过人工接头进行融合。融合蛋白在大肠杆菌中表达后，Ｗｅｓｔｅｒｎｂｌｏｔ分析表明，分子量约为３７ｋＤ；活性检测结果证实，该融合蛋白兼具有ＴＮＦ抗肿瘤活性和结合ＩＬ－６受体的能力，在高表达ＩＬ－６受体的人骨髓瘤细胞上测得的细胞毒活性较同样位点突变的ＴＮＦ高约３倍。
A mutant tumor necrosis factor(TNF) was constructed by PCR, in order to delete the toxicity and side effects of native TNF to human cells. As many kinds of tumor cells expressing high level IL-6 receptor,it was fused that the cDNA of IL-6and the mutant TNF gene with an artificial linker,and expressed it in E. coli. Western blot indicated that the molecular weight of the recombinant protein was about 37 kD. It presented activity of both antitumor and IL-6 receptor affinity. Fusion protein showed three times higher cytotoxicity than the mutant TNF to human myeloma cells expressing high IL-6 receptor.
