Construction and HepG2 cell line expression of the plasmid containing IFN-5α gene and hepatitis B virus DNA with X gene deletion

Objective To construct an X-gene defect and IFN gene contained HBV expression plasmid and explore its expression effect in HepG2 cell line. Methods By employing pBR322-B-HBV plasmid which contained type adrⅠHBV DNA, we destroyed HBV X-gene by inserting mutation and connected the defect HBV with IFN sequence. After recombination, it was introduced into a mammalian plasmid and was constructed as the objective plasmid. At the same time, two control groups were constructed. One was pcDNA3-ES-HBV2, which contained the full length of HBV DNA. The other was pcDNA3-KN-F1F2, which contained the X-gene defect HBV DNA. Then we transfected HepG2 cells with all the plasmid. After the cells were screened by G418, the X-gene defect and IFN gene contained HBV(KN-F1F2-IFN) and IFN protein from culture medium were detected by fluorescence- quantitative-PCR and ELISA respectively. Results pcDNA3-KN-F1F2-IFN, as the objective plasmid, was constructed successfully; contrary with the control virus, the amounts of both HBV and HBsAg were lower; both IFN mRNA and IFN protein were detected.Conclusions An X-gene defect and IFN gene contained HBV expression plasmid was constructed successfully and it can be expressed in HepG2 cell line.