Hepatitis B virus is inhibited by RNA interference in cell culture and in mice.
OBJECTIVE
For chronic hepatitis B virus (HBV) infection the effects of current therapies are limited. Recently, RNA interference (RNAi) of virus-specific genes has emerged as a potential antiviral mechanism. Here we studied the effects of HBV-specific 21-bp short hairpin RNAs (shRNAs) targeted to the surface antigen (HBsAg) region and the core antigen (HBcAg) region both in a cell culture system and in a mouse model for HBV replication.


METHODS
HBsAg and hepatitis B e antigen (HBeAg) in the media of the cells and in the sera of the mice were analyzed by time-resolved immunofluorometric assay, intracellular HBcAg by immunofluorescence assay, HBsAg and HBcAg in the livers of the mice by immunohistochemical assay, HBV DNA by fluorogenic quantitative polymerase chain reaction (FQ-PCR) and HBV mRNA by semi-quantitative reverse transcriptase PCR (RT-PCR).


RESULTS
Transfection with the shRNAs induced an RNAi response. Secreted HBsAg was reduced by >80% in cell culture and >90% in mouse serum, and HBeAg was also significantly inhibited. Immunofluorescence detection of intracellular HBcAg revealed 76% reduction. In the liver tissues by immunohistochemical detection, there were no HBsAg-positive cells and >70% reduction of HBcAg-positive cells for shRNA-1. And for shRNA-2 the detection of HBsAg and HBcAg also revealed substantial reduction. The shRNAs caused a significant inhibition in the levels of viral mRNA relative to the controls. HBV DNA was reduced by >40% for shRNA-1 and >60% for shRNA-2.


CONCLUSIONS
RNAi is capable of inhibiting HBV replication and expression in vitro and in vivo and thus may constitute a new therapeutic strategy for HBV infection.
Ying
Ruo-Su
RS
Department of Infectious Diseases, Xiangya Hospital, Central South University, Changsha 410008, Hunan, People's Republic of China.
Zhu
Cai
C
Fan
Xue-Gong
XG
Li
Ning
N
Tian
Xue-Fei
XF
Liu
Hong-Bo
HB
Zhang
Bao-Xin
BX
D000818:Animals; D045744:Cell Line, Tumor; D004279:DNA, Viral / Q000378:metabolism; D005260:Female; D006509:Hepatitis B / Q000821:virology; D006511:Hepatitis B Antigens / Q000235:genetics / Q000378:metabolism*; D006515:Hepatitis B virus / Q000187:drug effects*; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D034622:RNA Interference; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics* / Q000378:metabolism; D012367:RNA, Viral / Q000235:genetics / Q000378:metabolism; D014162:Transfection; D014779:Virus Replication
D004279:DNA, Viral; D006511:Hepatitis B Antigens; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D012367:RNA, Viral