Prokaryotic expression of fusion gene A?-HBcAg and analysis of the immunoreactivity and immunogenicity of the expression protein / 西安交通大学学报(医学版)

ABSTRACT

Objective To study the prokaryotic expression of fusion gene A?-HBcAg and analyze the immunoreactivity and immunogenicity of expression protein. Methods Recombinant plasmid pBV220/A?-HBcAg was transformed into E.coli DH5?, and expressed by temperature inducing. The bacteria were split by ultrasonic wave. The expression of the fusion protein was studied by SDS-PAGE and Coomassie brilliant blue staining. The immunoreactivity of the fusion protein was determined using ELISA. After immunized intraperitoneally with the fusion protein, 5 Balb/c mice's sera titers of anti- A? and anti-HBc were evaluated by ELISA. Results Fusion protein was in sediment of the split bacteria as inclusion bodies and its expression level was 5% of the total sediment protein. The fusion protein had both immunoreactivity of A? and HBcAg. The titers of anti-A? and anti-HBc were very low after 3 times of immunization. After immunization for 5 times, the titers reached 1∶800 and 1∶3 200 for anti-A? and anti-HBc, respectively. Conclusion Recombinant gene A?-HBcAg can be expressed in E.coli DH5? and the expression protein has certain immunoreactivity and immunogenicity. It indicates that further work should be done to enhance the expression level of fusion gene A?-HBcAg and improve the immunogenicity of the fusion protein.