The goal of the work is to advance our original studies on developing the scientific principles required for RNAi-based clinical therapeutics. Our plan is to provide a platform for safe and effective transcription-based RNA interference (RNAi) into vital organs such as the liver. We are specifically interested in developing a therapeutic approach for Hepatitis C Virus Infection (HCV) for which there is still an unmet clinical need. Until recently, research in this area has been hampered by the lack of ability to study replication from an intact viral infection in cell culture and the paucity of animal models. As a result, HCV replicons have been the primary means to study viral replication. We have discovered that some RNAi targets are effective against replicons but relatively inert against bona-fide viral infection that shares identical target sequences. We plan to re-evaluate various regions of the HCV genome for RNAi knockdown based on our new models and information regarding shRNA-vector biology. In addition, we will attempt to definitively evaluate the effectiveness of targeting the HCV minus strand because it is produced in much lower amounts in infected cells. We will determine if targeting both strands simultaneously will provide better protection and lessen the likelihood of quasi-species formation. We plan to use cell culture and humanized mouse liver models with our newly developed recombinant AAV vectors and determine the validity of RNAi as a means to protect against HCV exposure as well as elimination of the virus after establishment of a sustained infection. By the end of the granting period, we believe we will be able to provide important insights into the parameters required for effective vector-based RNAi in vivo and have a robust clinically relevant means of treating HCV infection as a single therapy and/or in combination with other non-nucleic acid based therapeutics.

Public Health Relevance

The goal of this work is to develop the scientific principles and pave the way to develop a safe and efficacious clinical therapy for Hepatitis C virus infection using RNA interference (RNAi). RNAi is a powerful new technology for turning off unwanted genes such as those present in a viral pathogen. The new anti-HCV RNAI therapeutics will be tested for their ability to eliminate and/or prevent HCV infection in newer clinically relevant cell culture and rodent models of HCV infection.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI071068-10
Application #
8887283
Study Section
Gene and Drug Delivery Systems Study Section (GDD)
Program Officer
Koshy, Rajen
Project Start
2006-08-01
Project End
2016-07-31
Budget Start
2015-08-01
Budget End
2016-07-31
Support Year
10
Fiscal Year
2015
Total Cost
Indirect Cost
Name
Stanford University
Department
Pediatrics
Type
Schools of Medicine
DUNS #
009214214
City
Stanford
State
CA
Country
United States
Zip Code
94304
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Kim, Hak Kyun; Fuchs, Gabriele; Wang, Shengchun et al. (2017) A transfer-RNA-derived small RNA regulates ribosome biogenesis. Nature 552:57-62
Valdmanis, Paul N; Gu, Shuo; Chu, Kirk et al. (2016) RNA interference-induced hepatotoxicity results from loss of the first synthesized isoform of microRNA-122 in mice. Nat Med 22:557-62
Haussecker, Dirk; Kay, Mark A (2015) RNA interference. Drugging RNAi. Science 347:1069-70
Valdmanis, P N; Roy-Chaudhuri, B; Kim, H K et al. (2015) Upregulation of the microRNA cluster at the Dlk1-Dio3 locus in lung adenocarcinoma. Oncogene 34:94-103
Gu, Shuo; Zhang, Yue; Jin, Lan et al. (2014) Weak base pairing in both seed and 3' regions reduces RNAi off-targets and enhances si/shRNA designs. Nucleic Acids Res 42:12169-76
Roy-Chaudhuri, Biswajoy; Valdmanis, Paul N; Zhang, Yue et al. (2014) Regulation of microRNA-mediated gene silencing by microRNA precursors. Nat Struct Mol Biol 21:825-32
Gu, Shuo; Jin, Lan; Zhang, Yue et al. (2012) The loop position of shRNAs and pre-miRNAs is critical for the accuracy of dicer processing in vivo. Cell 151:900-911
Parameswaran, Poornima; Sklan, Ella; Wilkins, Courtney et al. (2010) Six RNA viruses and forty-one hosts: viral small RNAs and modulation of small RNA repertoires in vertebrate and invertebrate systems. PLoS Pathog 6:e1000764
Grimm, Dirk; Wang, Lora; Lee, Joyce S et al. (2010) Argonaute proteins are key determinants of RNAi efficacy, toxicity, and persistence in the adult mouse liver. J Clin Invest 120:3106-19

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