利用冰核蛋白N-端结构域在大肠杆菌表面展示人存活蛋白

Display of Human Survivin on Surface of Escherichia coli Using N-terminal Domain of Ice Nucleation Protein

存活蛋白(survivin)是高度特异的广谱肿瘤相关抗原,利用冰核蛋白(ice nucleation protein,INP)表面展示系统研究在大肠杆菌细胞表面展示人存活蛋白的可行性。将人存活蛋白基因片段和报告基因Cherry融合到冰核蛋白N-端,构建表面展示载体p ET-INP-CHY-SUV并转化大肠杆菌BL21(DE3)。重组菌经IPTG诱导后可检测到红荧光,荧光强度在胰蛋白酶的作用下降低,完整细胞ELISA实验及免疫荧光实验可检测和观察到绿荧光,表明人存活蛋白在重组菌中得到表达,并且成功展示于细胞表面,为进一步研制新型的肿瘤DNA疫苗奠定基础。

Survivin is a highly specific broad-spectrum tumor-associated antigens. The feasibility of displaying human survivin protein on the surface of Escherichia coli（E. coli） cells was studied using an ice nucleation protein（INP） surface display system. The survivin gene fragment and the Cherry reporter gene were fused to the N-terminus of INP, and the surface displayed vector p ET-INP-CHY-SUV was constructed and transformed into E. coli BL21（DE3）. Red fluorescence of recombinant bacteria can be detected after being induced by IPTG, and the intensity decreased by digestion of trypsin. The whole-cell ELISA and immune fluorescence assay showed the green fluorescence. The above results suggested that human survivin was expressed in recombinant bacteria and successfully displayed on the cell surface and lay the foundation for further development of new tumor DNA vaccine.