Construction and expression of a recombinant Bifidobacterium bifidum vaccine of Schistosoma japonicum

Objective To construct a recombinant Bifidobacterium bifidum (Bb) vaccine[Bb (pGEX-Sj26GST-Sj14-3-3)] of Schistosoma japonicum (Sj) and analyze the expression of the fusion gene Sj26GST-Sj14-3-3 of Sj in Bb. Methods The recombinant plasmid pGEX-Sj26GST-Sj14-3-3 was electroporated into Bb to construct a recombinant Bb (pGEX-Sj26GST-Sj14-3-3) vaccine. After induction with isopropyl-β-D-thiogalactoside (IPTG), double restriction enzymes digestion and polymerase chain reaction (PCR) were used to identify the recombinant Bb (pGEX-Sj26GST-Sj14-3-3), expression of the recombinant protein was analyzed and identified by sodium dodecyl sulfonate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting. Results The recombinant plasmid pGEX-Sj26GST-Sj14-3-3 was successfully transformed into Bb identified by double restriction enzymes digestion and PCR. SDS-PAGE analysis showed that the relative molecular mass of the expressed recombinant protein was approximately 67 × 103. The expressed protein could be recognized by the immune sera from rabbits infected with Sj by Western blotting. Conclusions The recombinant Bb (pGEX-Sj26GST-Sj14-3-3) vaccine of Sj is successfully constructed. The fusion gene Sj26GST-Sj14-3-3 can be expressed in recombinant Bb and the expressed target protein shows specific antigenicity. Key words: Schistosoma japonicum; Fusion gene; Bifidobacterium bifidum; Vaccines