目的　构建人源抗 HAVFab真核表达载体并进行表达。方法采用DNA重组技术将抗体重轻链基因与信号肽基因连接 ,并分别插入真核表达载体 pCdhfr1和pCDNA3 1;以脂质体介导法转染CHO细胞 ,经G418筛选细胞 ,ELISA检测Fab基因的表达。结果成功地构建了Fab表达载体。转染细胞后 ,经ELISA检测 ,细胞培养上清中有抗原结合活性的Fab片段。结论Fab真核表达载体的构建及其在CHO细胞中的表达 ,为抗体编码基因在CHO细胞中稳定表达奠定了基础 Objective To construct and express human anti-HAVFab eukaryotic expression vector. Methods The heavy chain gene of the antibody was ligated with the signal peptide gene by DNA recombination technique and inserted into the eukaryotic expression vector pCdhfr1 and pCDNA3 1, respectively. The CHO cells were transfected by lipofectamine and the cells were selected by G418. The Fab gene expression. Results The Fab expression vector was successfully constructed. After transfection, the Fab fragments with antigen-binding activity in the cell culture supernatant were detected by ELISA. Conclusion The construction of Fab eukaryotic expression vector and its expression in CHO cells laid the foundation for the stable expression of antibody encoding gene in CHO cells