Objective: To construct a stable cell line with permanent secretion of recombinant hepatitis B virus (HBV) vector, which express blasticidin resistant gene.
Methods: Replication-defective HBV vector, pCH-BsdR, which express blasticidin resistance gene was constructed by deleting the HBV genes and inserting the blasticidin resistance gene into the S region. The G418-resistant, the packaging signal deleted HBV helper plasmid, pcDNA3.1-CH3142, and the HBV vector pCH-BsdR were cotransfected into HepG2 cells. Cell clones were selected by the adding of both blasticidin and G418, then serial detection were done.
Results: After 36 cell clones were picked and expanded. Three cell clones were defined as the best. Quantity of their HBV DNA were 4.1 x 10(6), 3.6 x 10(6) and 1.2 x 10(6) copies/ml, respectively. Enveloped recombinant, but not wild type HBV were confirmed in the culture medium.
Conclusions: The stable cell lines can realize large preparation of recombinant HBV virions. This will contribute to the use of HBV vector for gene therapy and HBV susceptible cell lines screening.