关键词: 细粒棘球绦虫；EgEno基因；克隆；表达；免疫诊断

Abstract:

Objective To clone and express EgEno gene of Echinococcus granulosus，and to investigate the immunogenicity and diagnostic value of recombinant EgEno. Methods Total RNAS of E. granulosus was extracted and reversedly transcripted to cDNA. EgEno gene was amplified from cDNA and inserted into vector pET28a. The recombinant plasmid pET28a?EgEno was trans? formed into E. coli BL21（DE3）for expression under the induction of IPTG. The expressed product was identified by SDS?PAGE and Western blotting. The purified recombinant EgEno protein was detected by ELISA with the sera of cystic echinococcosis pa? tients，healthy persons and other patients. Results The EgEno gene was successfully amplified from cDNA of E. granulosus and a fusion protein was expressed in E. coli BL21（DE3）. The molecular weight of the expressed protein was around 50 kDa. The re? sult of Western blotting indicated that the antigenicity of the protein was specific. The sensitivity of diagnosis by ELISA for cystic echinococcosis was 81.25%. Conclusion EgEno of E. granulosus is cloned and expressed in E. coli BL21（DE3）successfully， which might be used as a candidate antigen of immunodiagnosis for cystic echinococcosis.

Key words: Echinococcus granulosus；Enolase；Clone；Expression；Immunodiagnosis