Combinatorial RNA Interference Therapy Prevents Selection of Pre-existing HBV Variants in Human Liver Chimeric Mice.
Selection of escape mutants with mutations within the target sequence could abolish the antiviral RNA interference activity. Here, we investigated the impact of a pre-existing shRNA-resistant HBV variant on the efficacy of shRNA therapy. We previously identified a highly potent shRNA, S1, which, when delivered by an adeno-associated viral vector, effectively inhibits HBV replication in HBV transgenic mice. We applied the "PICKY" software to systemically screen the HBV genome, then used hydrodynamic transfection and HBV transgenic mice to identify additional six highly potent shRNAs. Human liver chimeric mice were infected with a mixture of wild-type and T472C HBV, a S1-resistant HBV variant, and then treated with a single or combined shRNAs. The presence of T472C mutant compromised the therapeutic efficacy of S1 and resulted in replacement of serum wild-type HBV by T472C HBV. In contrast, combinatorial therapy using S1 and P28, one of six potent shRNAs, markedly reduced titers for both wild-type and T472C HBV. Interestingly, treatment with P28 alone led to the emergence of escape mutants with mutations in the P28 target region. Our results demonstrate that combinatorial RNAi therapy can minimize the escape of resistant viral mutants in chronic HBV patients.
Graduate Institute of Microbiology, National Taiwan University, Taipei, Taiwan.|Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.
Yao-Ming
YM
Shih
Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.
Cheng-Pu
CP
Sun
Department of Computer Science, Iowa State University, Ames, Iowa, United States of America.
Hui-Hsien
HH
Chou
Department of Clinical Laboratory Sciences and Medical Biotechnology, National Taiwan University, Taipei, Taiwan.
Tzu-Hui
TH
Wu
CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
Chun-Chi
CC
Chen
Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.
Ping-Yi
PY
Wu
Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.
Yu-Chen
YC
Enya Chen
Department of Molecular and Cellular Biology, Center for Cell and Gene Therapy, Stem Cells and Regenerative Medicine Center, Baylor College of Medicine, One Baylor Plaza, BCM505, Alkek Building, N1010.07, Houston, TX 77030, USA.
Karl-Dimiter
KD
Bissig
Graduate Institute of Microbiology, National Taiwan University, Taipei, Taiwan.|Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.
Mi-Hua
MH
Tao
D000818:Animals; D019295:Computational Biology / Q000379:methods; D004270:DNA, Circular; D018076:DNA, Complementary; D004279:DNA, Viral; D000229:Dependovirus / Q000235:genetics; D004195:Disease Models, Animal; D015316:Genetic Therapy; D014644:Genetic Variation; D005822:Genetic Vectors / Q000008:administration & dosage / Q000235:genetics; D006515:Hepatitis B virus / Q000235:genetics*; D019694:Hepatitis B, Chronic / Q000628:therapy / Q000821:virology*; D006801:Humans; D016031:Liver Transplantation; D051379:Mice; D008822:Mice, Transgenic; D009154:Mutation; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics; D012367:RNA, Viral / Q000235:genetics; D018183:Transplantation Chimera; D019562:Viral Load
D004270:DNA, Circular; D018076:DNA, Complementary; D004279:DNA, Viral; D034741:RNA, Small Interfering; D012367:RNA, Viral