摘要
OBJECTIVES: To construct a DNA vaccine capable of expressing the S gene of hepatitis B virus (HBV)and evaluate the expression of the recombinant S gene in vitro and in vivo.METHODS: A cloned S-X gene fragment was inserted into an eukaryote expression vector to construct arecombinant expressing plasmid pCMV-SX. The recombinant plasmid was transcribed in vitro with a T7promoter transcription system and transfected into a human hepatoblastoma cell line HepG2. Theexpression of the S gene was detected by Northern blot hybridization, Western blot hybridization, andenzyme-linked immunosorbent assay (ELISA), respectively. BALB/c mice were inoculated with therecombinant plasmid, and the efficiency of DNA-based immunization in eliciting anti-HBs was evaluatedby ELISA.RESULTS: In vitro transcription of the subcloned HBV S gene was confirmed by Northern blothybridization. The results of Western blot hybridization and ELISA showed that the S gene was expressedexactly in HepG2. In immune experiment, 2 of 10 immunized mice were shown to induce antibody againstHBsAg.CONCLUSION: The recombination and expression of the S gene can be achieved successfully in vitro.And the recombinant plasmid is able to elicit humoral immune response in mice.
