目的　获得鼠抗人精浆蛋白单克隆抗体Fab段基因并在大肠杆菌中表达。方法　从分泌抗人精浆蛋白单克隆抗体的杂交瘤细胞系E4B7中提取总RNA ,用逆转录聚合酶链反应技术 (RT PCR)克隆Fd段和κ链基因 ;构建到噬粒pComb3中 ;并用ELISA、Westernblotting和免疫细胞化学分析证明表达的Fab段特异性结合人精浆蛋白。结果　从分泌抗人精浆蛋白的鼠单克隆抗体杂交瘤细胞系E4B7中克隆出了重链Fd段和κ链基因 ,经序列测定表明 ,Vκ 属于鼠免疫球蛋白ⅩⅢ家族 ,VH与鼠免疫球蛋白MUSIGHAEI同源性最高。将该Fd和κ链基因克隆到表达载体pComb3中 ,在大肠杆菌中获得了表达。结论　ELISA、Westernblotting和免疫细胞化学分析表明 ,表达的Fab段可以特异性的与人精浆蛋白结合 Objective To obtain the Fab fragment of murine anti-human seminal plasma monoclonal antibody and express in Escherichia coli. Methods The total RNA was extracted from the hybridoma cell line E4B7 secreting anti-human seminal plasma monoclonal antibody. The Fd fragment and the κ-chain gene were cloned by reverse transcription-polymerase chain reaction (RT PCR) and constructed into phagemid pComb3. ELISA, Western blotting and immunocytochemistry analysis demonstrated that the expressed Fab fragments specifically bind to human seminoprotein. Results The heavy chain Fd fragment and the κ chain gene were cloned from the murine monoclonal antibody hybridoma cell line E4B7 secreting anti-human seminal plasma protein. The results of sequence analysis showed that Vκ belongs to murine immunoglobulin XIII family. VH and murine immunoglobulin Protein MUSIGHAEI homology highest. The Fd and kappa chain genes were cloned into the expression vector pComb3 and expressed in E. coli. Conclusion ELISA, Westernblotting and immunocytochemistry analysis show that the expressed Fab fragments can specifically bind to human seminiferous protein