Abstract: Objective To purify the specific IgE antibody related recombinant protein of Schistosoma japonicum and to identify its immunogenicity. Methods The recombinant plasmid Sj43B/pGEX 6p 1 was expressed in E. coli BL 21. The inclusion body of the fusion protein was washed by TNMFX buffer and separated by FPLC. After renaturation, the fusion protein was used to vaccinate the mice. The specific IgG and IgE antibodies were detected by dot ELISA and Western blotting analysis, respectively. Results Most of the proteins mixed with the inclusion body of the recombinant protein could be eliminated by washing with TNMFX buffer. The purified recombinant fusion protein could be obtained by FPLC separation. The experiment on mice immunized with the fusion protein showed that the specific IgE antibody was generated against the target part of the fusion protein,but not the specific IgG antibody. Conclusion The fusion protein expressed by the recombinant plasmid Sj43B/pGEX 6p 1 could induce specific IgE response of the immunized mice.

Key words: Schistosoma japonicum, IgE, fusion protein, inclusion body, protein purification