Abstract: Objective To clone and express the lactate dehydrogenase （LDH） gene of Taenia saginata asiatica and analyze the immunogenicity of the recombinant protein. Methods By screening the full length cDNA plasmid library，the coding region of LDH was amplified with PCR，and cloned into the prokaryotic expression vector pET-30a （+）, then expressed in E. coli BL21 with IPTG induction. The recombinant protein was detected by SDS-PAGE and purified by Ni-IDA affinity chromatography, and its immunogenicity was analyzed by Western blotting. Results PCR, double enzyme digestion and DNA sequencing confirmed that the recombinant expression plasmid was constructed. The expression products were obtained and purified by Ni-IDA affinity chromatography. Western blotting analysis of LDH recombinant protein testified that the recombinant protein could be recognized by sera of the Taenia saginata asiatica infected swine and the patient. Conclusions The LDH gene of Taenia saginata asiatica has been cloned and expressed，and the purified protein has been confirmed with immunogenicity.

Key words: Taenia saginata asiatica, Lactate dehydrogenas, Cloning, Prokaryotic expression