Abstract:

Objective To construct a prokaryotic expression vector of Clostridium difficile binary toxin（Cdt） A,to express and purify His-CdtA recombinant protein,and to analyze its immunogenicity. Methods The full-length sequence of cdtA was amplified by polymerase chain reaction（PCR） using RT 027 Clostridium difficile as template,which was introduced into Escherichia coli BL21 competent cells. The His-CdtA recombinant protein was induced,and the mice were immunized with the purified protein for analyzing the antibodies produced by the mice. Results The prokaryotic expression vector pET-28b-cdtA was successfully constructed,and a high concentration of His-CdtA recombinant protein was induced and purified. After immunizing mice,high-titer antibody of CdtA recombinant protein was produced. Conclusions The mice immunized with the purified His-CdtA recombinant protein produce high-titer anti-CdtA antibodies,which lay a foundation for the subsequent preparation of monoclonal antibodies against CdtA and the methodology of CdtA laboratory detection.

Key words: Clostridium difficile, Binary toxin A, Prokaryotic expression, Antibody, Immunogenicity