Effect of viral core protein mutant on HBV encapsidation / 中华传染病杂志

ABSTRACT

Objective To observe a recombinant mutant of HBV core protein for dominant negative gene therapy against HBV encapsidation in vitro. Methods C gene and S gene of HBV were acquired through PCR and subcloned into pGEM T to construct pGEM T C and pGEM T S respectively. After digestion and ligation of these two plasmids, pGEM T CS was constructed. The cloned gene was inserted into pcDNA3.1 + to construct pcDNA3.1 + CS, which was identified by DNA sequencing. The recombinant plasmids were transformed into HepG2 cells, and screened with G418. The resistant HepG2 cell clones were chosen to test the expression of core surface protein by RT PCR, and the expressing HepG2 clones were cultured with 10% HBV DNA positive human serum for 72 hours. The intracellular HBV particles were extracted and the DNA was subjected to dot hybridization. Results The analysis showed that the HepG2 cells expressing mutant C protein had capabilities to resist HBV invasion in varied degrees. The mutant C protein had a dominant negative role in the encapsidation of HBV compared with the naive part of core protein. Conclusions The production of recombinant mutant core protein has a potential value for gene therapy against HBV infection.