[Prokaryocytic expression of the shortened hepatitis B surface antigen and antigenic analysis].

Objective: To study the expression of the shortened hepatitis B surface antigen in prokaryocyte and detect the antigenic characters.

Methods: Firstly, the gene fragments coding the 152 and 124 amino acids of the carboxyl terminus of hepatitis B surface antigen (HBsAg) were amplified by polymerase chain reaction (PCR). Secondly, they were cloned to plasmid pBKS+, and the accuracy of those constructions were confirmed by restriction enzyme digestion and DNA sequencing. Then, they were cloned to prokaryocytic expression vector-plasmid pET32a(+). The recombinant plasmids were transfected into E.coli BL21 and induced to express with IPTG.

Results: The recombinant plasmids were successfully constructed. In E.coli BL21, the protein was expressed in a fusion fashion and could be recognized by monoclonal antibody against HBsAg with ELISA and Western blot.

Conclusion: The shortened HBsAg can be expressed in prokaryocyte.