Members of Flavivirus genus are the most important arthropod-borne viruses causing disease in humans. This genus includes viruses (West Nile virus (WNV), Japanese encephalitis virus (JEV) and Dengue virus (DENV)) that are re-emerging and becoming endemic in new areas of the world. Flaviviruses account for ~100 millions infections per year, with billions at risk and no specific therapy available. Although interferon (IFN) responses control the cell and tissue tropism of WNV and other flaviviruses, the specific effector molecules that restrict infection remain poorly characterized. The studies in this collaborative and inter-disciplinary project between the Diamond and Chanda laboratories will use genetic screens to identify novel interferon stimulated genes (ISG) that modulate flavivirus infection in specific cell types ex vivo and in vivo. Loss-of-function high-throughput genetic screens will be performed with a custom- generated GFP-marked shRNA library targeting ~700 mouse and human ISGs, to identify novel ISG that restrict infection of virulent and attenuated strains of WNV. Using stable cell lines that have targeted reductions or ectopic expression of candidate ISGs, we will define mechanistically how novel ISG effector molecules restrict specific steps in the viral lifecycle and influence infection outcome. In preliminary studies, we have identified several candidate inhibitory ISG (Ifi27, IFIT2, and IFITM3) that attenuate WNV infection, and already acquired or generated knockout mice. Using these mice, we will evaluate the function of these particular ISGs in restricting WNV replication in a cell-specific manner and in vivo. We hypothesize that specific ISGs have antiviral properties that differentially control WNV infection and spread, and that these demonstrate tissue and cell-type specificity. Overall, these experiments will more clearly define the interface between IFN control and flavivirus pathogenesis and possibly, guide strategies that modulate immunity to infection by this family of viruses.

Public Health Relevance

The continual outbreaks of flavivirus disease highlight a need for an expanded understanding of mechanisms of immune control. Insight into the cell-intrinsic immune processes that restrict flavivirus infection is essential for developing novel strategies to contain disease. These experiments will define the interface between IFN control and flavivirus pathogenesis and guide strategies that modulate immunity to infection by positive strand RNA viruses of global concern.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
1R01AI104972-01
Application #
8479609
Study Section
Virology - B Study Section (VIRB)
Program Officer
Leitner, Wolfgang W
Project Start
2013-01-01
Project End
2017-12-31
Budget Start
2013-01-01
Budget End
2013-12-31
Support Year
1
Fiscal Year
2013
Total Cost
$610,742
Indirect Cost
$157,953
Name
Washington University
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
068552207
City
Saint Louis
State
MO
Country
United States
Zip Code
63130
Pierson, Theodore C; Diamond, Michael S (2018) The emergence of Zika virus and its new clinical syndromes. Nature 560:573-581
Scott, Jason M; Lebratti, Tania J; Richner, Justin M et al. (2018) Cellular and Humoral Immunity Protect against Vaginal Zika Virus Infection in Mice. J Virol :
Fowler, Angela M; Tang, William W; Young, Matthew P et al. (2018) Maternally Acquired Zika Antibodies Enhance Dengue Disease Severity in Mice. Cell Host Microbe 24:743-750.e5
Jain, Prashant; Boso, Guney; Langer, Simon et al. (2018) Large-Scale Arrayed Analysis of Protein Degradation Reveals Cellular Targets for HIV-1 Vpu. Cell Rep 22:2493-2503
Johnson, Britney; VanBlargan, Laura A; Xu, Wei et al. (2018) Human IFIT3 Modulates IFIT1 RNA Binding Specificity and Protein Stability. Immunity 48:487-499.e5
Weiss, Christopher M; Trobaugh, Derek W; Sun, Chengqun et al. (2018) The Interferon-Induced Exonuclease ISG20 Exerts Antiviral Activity through Upregulation of Type I Interferon Response Proteins. mSphere 3:
Gorman, Matthew J; Caine, Elizabeth A; Zaitsev, Konstantin et al. (2018) An Immunocompetent Mouse Model of Zika Virus Infection. Cell Host Microbe 23:672-685.e6
Platt, Derek J; Smith, Amber M; Arora, Nitin et al. (2018) Zika virus-related neurotropic flaviviruses infect human placental explants and cause fetal demise in mice. Sci Transl Med 10:
Richner, Justin M; Himansu, Sunny; Dowd, Kimberly A et al. (2017) Modified mRNA Vaccines Protect against Zika Virus Infection. Cell 168:1114-1125.e10
Hasan, S Saif; Miller, Andrew; Sapparapu, Gopal et al. (2017) A human antibody against Zika virus crosslinks the E protein to prevent infection. Nat Commun 8:14722

Showing the most recent 10 out of 54 publications