文章通过特异的引物分别扩增出CTLA 4和FasL胞外区的cDNA ,将它们拼接后 ,克隆入真核表达载体pcDNA3 1( + )中 ,进行表达、纯化 ,获得CTLA 4 FasL融合蛋白。Westernblot分析显示了该融合蛋白具有CTLA4 胞外区和FasL胞外区的抗原性。体外试验表明 ,该融合蛋白可以结合Jurkat细胞表面的Fas受体和Raji细胞表面的B7分子 ,表明了该分子双特异性的特点。该融合蛋白能够直接诱导Jurkat细胞发生凋亡 ,且此凋亡效应伴随Raji细胞的参与而增强 ,初步证实了该分子的免疫抑制效应 ,从而为进一步研究该融合蛋白特性及应用奠定了基础。 The cDNA of extracellular domain of CTLA 4 and FasL were amplified by specific primers. After splicing, the cDNAs were cloned into the eukaryotic expression vector pcDNA3 1 (+) and expressed. The CTLA 4 FasL fusion protein was obtained. Westernblot analysis showed that the fusion protein has the antigenicity of CTLA4 extracellular domain and extracellular domain of FasL. In vitro experiments show that the fusion protein can bind to the surface of Jurkat cell receptors and B7 Raji cells B7 molecules, indicating that the molecular characteristics of bispecific. The fusion protein can directly induce apoptosis of Jurkat cells, and the apoptosis effect is enhanced with the involvement of Raji cells. The immunosuppressive effect of the fusion protein was initially confirmed, which laid the foundation for further study on the characteristics and application of the fusion protein.