目的克隆和表达日本血吸虫天冬酰胺酰基内肽酶(Sj32),探索该重组抗原在动物血吸虫病诊断方面的应用潜能。方法用PCR法从Sj32前体编码基因中克隆编码成熟体的基因片段,以pET-28(a)为表达载体,用大肠埃希菌表达,制备重组抗原(rSj32);应用ELISA方法检测待检血清,并比较rSj32、日本血吸虫可溶性虫卵抗原(SEA)以及重组诊断抗原rSj23对人工感染兔、小鼠及水牛血吸虫病的检测效果。结果成功表达了Sj32成熟体,表达产物rSj32的分子量为41 kDa,可用H is柱纯化,得率约为68.8 mg/L培养物。用rSj32检测人工感染兔、小鼠和水牛血清以及对照兔、小鼠和水牛血清,特异性分别为100.0%、96.7%和96.9%,敏感性分别为88.9%、85.0%和71.8%,该抗原对牛血清的敏感性略低于SEA和rSj23,其余检测结果三者相比无显著差异。结论rSj32在诊断动物血吸虫病方面具有研究和应用价值。 Objective To clone and express Schistosoma japonicum endopeptidase (Sj32) and explore its potential application in the diagnosis of schistosomiasis in animals. Methods The gene fragment encoding mature body was cloned from Sj32 precursor gene by PCR. The recombinant plasmid was expressed in Escherichia coli using pET-28 (a) as an expression vector. The recombinant antigen (rSj32) was detected by ELISA. Serum, and compared rSj32, Schistosoma japonicum soluble egg antigen (SEA) and the recombinant diagnostic antigen rSj23 in artificially infected rabbit, mouse and buffalo schistosomiasis detection. Results The mature Sj32 gene was successfully expressed. The expressed product rSj32 had a molecular weight of 41 kDa. The purified product was purified by H column and the yield was about 68.8 mg / L. The specificity of rSj32 for the detection of artificially infected rabbits, mice and buffalo sera, as well as for control rabbits, mice and buffalo sera, was 100.0%, 96.7% and 96.9%, respectively, with sensitivities of 88.9%, 85.0% and 71.8%, respectively The sensitivity to bovine serum was slightly lower than SEA and rSj23, the rest of the test results were no significant difference between the three. Conclusion rSj32 has the value of research and application in the diagnosis of schistosomiasis in animals.