高效表达乙型肝炎病毒表面抗原的CHO细胞株的建立

Construction of recombinant CHO cell strain for high expression of HBsAg

目的探索乙型肝炎病毒表面抗原（s）基因在CHO无血清细胞培养系统中的高效表达。方法构建包含乙肝病毒s基因的质粒，转染CHO细胞，经MTX筛选后对培养液上清中的表达产物进行血清学检测以及形态学的观察。结果获得了能高效稳定表达HBsAg的CHO细胞株，电镜下可观测到小球型和管型颗粒，ELISA检测表达产物滴度达到1：5000。结论成功构建高效表达乙型肝炎病毒s蛋白的CHO无血清培养细胞株，表达的HBsAg具有良好的抗原活性。

Objective To overexpress hepatitis B virus S gene in CHO cells cultured in serum-free media. Method Plasmid was constructed by cloning of HBV S gene and then it was transfected into CHO cells. After cell screen, the positive clones were identified and isolated into a serum-free media followed by the serological and morphological characterization of the expression product. Result CHO cell strains which can express HBsAg efficiently and stably were obtained. Spherical and filamentous HBsAg could be detected under electronic microscope. The titer of the expression product was up to 1 ： 5000. Conclusion Serum-free media cultured CHO cell strain for overexpression of HBsAg was successfully constructed and the expression product was high antigenic.