RESUMO
Objective:In the past study, a plasmid of pcDNA3 hCG? C3d3 had been constructed. It was suggested that the fusing protein be expressed by the pcDNA3 hCG? C3d3 plasmid both in the transient expression system in COS 7 cells, and the stable expression system in CHO cells. In the present research, it would be testified that the C3d molecular adjuvant could improve the immunogenicity of the hCG? DNA immunization or not. Methods:BALB/C mice of 6 weeks old were immunized intramuscularly two times at interval of 3 weeks by the plasmid pcDNA3, pcDNA3 hCG?, pcDNA3 hCG? C3d3 at dosage of 5, 10, 20 pmol, respectively. The anti hCG? antibody titers were determined by indirect ELISA in 6 weeks of last immunization. Results:The result showed that the C3d molecular adjuvant could increase significantly the titer of anti hCG? antibody in a dose dependent manner after DNA immunization.Conclusion:The C3d molecular adjuvant does improve the humoral immunity of the hCG? DNA immunization, which would be helpful for technical progress and clinical trial of the contraceptive vaccine. [