关键词: 日本血吸虫, 21.7kDa膜蛋白分子, 表达及特性分析

Abstract: 　Objective To express, purify and characterize the 21.7 kDa membrane protein of Chinese strain S. japonicum (SjC21.7). Methods The gene of SjC21.7 was subcloned into the expression vector pGEX 4T 3 to form recombinant plasmid. The recombinant plasmids were transformed into E. coli BL21 and the GST SjC21.7 fusion protein was expressed by IPTG induction. The recombinant SjC21.7 molecule was prepared by affinity chromatography and digested by thrombin. The Kunming strain mice were immunized with the recombinant SjC21.7 molecule to produce anti SjC21.7 antibody. The purified SjC21.7 was recognized by the immunized mouse serum and the sera of rabbits infected by S. japonicum . Results The SjC21.7 gene was subcloned into expression vector pGEX 4T 3, then transformed into E.coli BL21 to express the GST SjC21.7 fusion protein. The recombinant SjC21.7 molecule obtained from the fusion protein could stimulate the mice to produce a high titer of specific antibody and could be recognized by sera of both the immunized and infected rabbits. The sera of immunized mice could also recognize the 21.7 kDa protein molecule of the adult worm antigen (AWA). Conclusion The recombinant and purified SjC21.7 was prepared and showed similar immunological characteristics to the natural SjC21.7 molecule, providing a basis for further investigation of the immunological protection of the recombinant SjC21.7.

Key words: Schistosoma japonicum, 21.7 kDa membrane protein, expression and characterization