Small molecules targeting the bromodomain-acetyl lysine interaction have emerged as novel epigenetic therapeutics in hematological and virological disease. We showed recently that these inhibitors reactivate HIV from latency in cultured cells and primary T-cell models of latency. Importantly, our data demonstrate that bromodomain inhibitors activate HIV latency by a Tat-independent mechanism, enhance release of active P-TEFb from the inhibitory 7SK ribonucleoprotein complex and implicate an unrecognized bromodomain and extraterminal domain (BET) family member, BRD2, in establishing HIV latency. We propose, in a multi-investigator effort, a set of highly integrated experiments to advance our understanding how the targeting of bromodomain proteins reverses HIV latency at the molecular level with a specific focus on primary latently infected T cells. The proposed studies represent a new line of investigations within the CARE Collaboratory and are designed to conclusively determine if bromodomain inhibitors represent a promising new strategy to purge HIV from latency in patients. In the first specific aim, the laboratories of Melanie Ott, Matija Peterlin, Jonathan Karn and Leor Weinberger propose to characterize the molecular mechanism of bromodomain inhibitor action in HIV latency. Specifically, we will perform an in-depth characterization of the interaction of BRD2 and BRD8 with P-TEFb and associated candidate proteins and will apply 3C to 5C chromosome conformation capture assays as well as single-cell time-lapse microscopy combined with computational modeling to study transcriptional changes induced by bromodomain inhibitors at the HIV LTR. In the second specific aim, the laboratories of Robert Siliciano, David Margolis, Vicente Planelles and Eric Verdin will perform comprehensive studies in primary T cell models and patient-derived cells to test the therapeutic efficiencies of bromodomain inhibitors alone or in combination with other latency-purging drugs. Specific emphasis lies on the knockdown of individual BET proteins in primary T cells and studies of a new dually fluorescence-labeled reporter virus that allows identification of latently infected T cells without prior reactivation. Collectively, these studies will significantly enhance our molecular understanding of the role of bromodomain-containing proteins in HIV transcription and will inform novel drug development strategies to effectively purge viral reservoirs in HIV-infected individuals.

Public Health Relevance

Latently infected memory T cells represent a major barrier to eradicating HIV from infected individuals, and efforts are underway to reverse HIV latency and eradicate HIV from infected individuals. The goal of this proposal is to evaluate the therapeutic potential of newly developed bromodomain inhibitors as novel latency-purging agents and to determine the molecular mechanism how these inhibitors act on the HIV LTR.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Program--Cooperative Agreements (U19)
Project #
5U19AI096113-03
Application #
8725367
Study Section
Special Emphasis Panel (ZAI1-JBS-A (M1))
Project Start
Project End
Budget Start
2013-07-01
Budget End
2014-06-30
Support Year
3
Fiscal Year
2013
Total Cost
$55
Indirect Cost
$18,826
Name
University of North Carolina Chapel Hill
Department
Type
DUNS #
608195277
City
Chapel Hill
State
NC
Country
United States
Zip Code
27599
Honeycutt, Jenna B; Sheridan, Patricia A; Matsushima, Glenn K et al. (2015) Humanized mouse models for HIV-1 infection of the CNS. J Neurovirol 21:301-9
King, Helen L; Keller, Samuel B; Giancola, Michael A et al. (2014) Pre-exposure prophylaxis accessibility research and evaluation (PrEPARE Study). AIDS Behav 18:1722-5
Manson McManamy, Mary E; Hakre, Shweta; Verdin, Eric M et al. (2014) Therapy for latent HIV-1 infection: the role of histone deacetylase inhibitors. Antivir Chem Chemother 23:145-9
Spivak, Adam M; Andrade, Adriana; Eisele, Evelyn et al. (2014) A pilot study assessing the safety and latency-reversing activity of disulfiram in HIV-1-infected adults on antiretroviral therapy. Clin Infect Dis 58:883-90
Duverger, Alexandra; Wolschendorf, Frank; Anderson, Joshua C et al. (2014) Kinase control of latent HIV-1 infection: PIM-1 kinase as a major contributor to HIV-1 reactivation. J Virol 88:364-76
Denton, Paul W; Long, Julie M; Wietgrefe, Stephen W et al. (2014) Targeted cytotoxic therapy kills persisting HIV infected cells during ART. PLoS Pathog 10:e1003872
Abreu, Celina M; Price, Sarah L; Shirk, Erin N et al. (2014) Dual role of novel ingenol derivatives from Euphorbia tirucalli in HIV replication: inhibition of de novo infection and activation of viral LTR. PLoS One 9:e97257
Archin, Nancie M; Margolis, David M (2014) Emerging strategies to deplete the HIV reservoir. Curr Opin Infect Dis 27:29-35
Liu, Pingyang; Xiang, Yanhui; Fujinaga, Koh et al. (2014) Release of positive transcription elongation factor b (P-TEFb) from 7SK small nuclear ribonucleoprotein (snRNP) activates hexamethylene bisacetamide-inducible protein (HEXIM1) transcription. J Biol Chem 289:9918-25
Persaud, Deborah; Patel, Kunjal; Karalius, Brad et al. (2014) Influence of age at virologic control on peripheral blood human immunodeficiency virus reservoir size and serostatus in perinatally infected adolescents. JAMA Pediatr 168:1138-46

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