Inhibition of hepatitis B virus replication by APOBEC3G in vitro and in vivo.
OBJECTIVE
To investigate the effect of APOBEC3G mediated antiviral activity against hepatitis B virus (HBV) in cell cultures and replication competent HBV vector-based mouse model.


METHODS
The mammalian hepatoma cells Huh7 and HepG2 were cotransfected with various amounts of CMV-driven expression vector encoding APOBEC3G and replication competent 1.3 fold over-length HBV. Levels of HBsAg and HBeAg in the media of the transfected cells were determined by ELISA. The expression of HBcAg in transfected cells was detected by western blot. HBV DNA and RNA from intracellular core particles were examined by Northern and Southern blot analyses. To assess activity of the APOBEC3G in vivo, an HBV vector-based model was used in which APOBEC3G and the HBV vector were co-delivered via high-volume tail vein injection. Levels of HBsAg and HBV DNA in the sera of mice as well as HBV core-associated RNA in the liver of mice were determined by ELISA and quantitative PCR analysis respectively.


RESULTS
There was a dose dependent decrease in the levels of intracellular core-associated HBV DNA and extracellular production of HBsAg and HBeAg. The levels of intracellular core-associated viral RNA also decreased, but the expression of HBcAg in transfected cells showed almost no change. Consistent with in vitro results, levels of HBsAg in the sera of mice were dramatically decreased. More than 1.5 log10 decrease in levels of serum HBV DNA and liver HBV RNA were observed in the APOBEC3G-treated groups compared with the control groups.


CONCLUSIONS
These findings indicate that APOBEC3G could suppress HBV replication and antigen expression both in vivo and in vitro, promising an advance in treatment of HBV infection.
Lei
Yan-Chang
YC
Division of Clinical Immunology, Department of Infectious Diseases, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030, Hubei Province, China.
Hao
You-Hua
YH
Zhang
Zheng-Mao
ZM
Tian
Yong-Jun
YJ
Wang
Bao-Ju
BJ
Yang
Yan
Y
Zhao
Xi-Ping
XP
Lu
Meng-Ji
MJ
Gong
Fei-Li
FL
Yang
Dong-Liang
DL
D000071480:APOBEC-3G Deaminase; D000818:Animals; D006528:Carcinoma, Hepatocellular / Q000235:genetics / Q000378:metabolism / Q000821:virology; D045744:Cell Line, Tumor; D003564:Cytidine Deaminase; D004261:DNA Replication / Q000187:drug effects; D004279:DNA, Viral / Q000235:genetics / Q000378:metabolism; D005260:Female; D015967:Gene Expression Regulation, Viral / Q000187:drug effects / Q000502:physiology; D006509:Hepatitis B / Q000628:therapy; D006514:Hepatitis B Surface Antigens / Q000235:genetics / Q000378:metabolism; D006513:Hepatitis B e Antigens / Q000235:genetics / Q000378:metabolism; D006515:Hepatitis B virus / Q000235:genetics / Q000502:physiology*; D006801:Humans; D008113:Liver Neoplasms / Q000235:genetics / Q000378:metabolism / Q000821:virology; D051379:Mice; D008807:Mice, Inbred BALB C; D009700:Nucleoside Deaminases / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012367:RNA, Viral / Q000235:genetics / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D014779:Virus Replication / Q000187:drug effects* / Q000502:physiology
D004279:DNA, Viral; D006514:Hepatitis B Surface Antigens; D006513:Hepatitis B e Antigens; D012333:RNA, Messenger; D012367:RNA, Viral; D012097:Repressor Proteins; D009700:Nucleoside Deaminases; D000071480:APOBEC-3G Deaminase; C464924:APOBEC3G protein, human; D003564:Cytidine Deaminase