Objective       To determine the effect of interferon-induced protein bone marrow stromal antigen 2 (BST-2) on the replication and release of hepatitis B virus (HBV).       Methods       Human hepatoma cell line HepG2.2.15 was treated with different concentrations of interferon

and the expression level of BST-2 was determined by Western blotting and quantitative PCR. Eukaryotic expression plasmid pCDNA3.1-BST2-FLAG was constructed and transferred into HepG2.2.15 cells. The levels of HBV surface antigen (HBsAg) and HBV e antigen (HBeAg) in cell cultures were detected by enzyme-linked immunosorbent assay (ELISA). HBV mRNA levels were detected by fluorescence quantitative PCR

while HBV DNA levels were detected by Southern blotting. Then

BST-2 antagonist protein

HIV Vpu

was added to inhibit BST-2

and HBsAg

HBeAg

HBV mRNA and HBV DNA levels were detected with the same methods as above.       Results       After transfection of HepG2.2.15 cells with pCDNA3.1-BST2-FLAG

HBsAg and HBeAg levels in cell cultures and intracellular HBV mRNA and DNA levels were decreased significantly (P0.05). After HIV Vpu protein was added

the inhibitory effect of BST2 was antagonized

and HBV replication was recovered partially.       Conclusion      BST-2 inhibits the replication and release of HBV

and the inhibitory effect can be antagonized with HIV Vpu protein.