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
Davis, Zachary B; Cogswell, Andrew; Scott, Hamish et al. (2016) A Conserved HIV-1-Derived Peptide Presented by HLA-E Renders Infected T-cells Highly Susceptible to Attack by NKG2A/CD94-Bearing Natural Killer Cells. PLoS Pathog 12:e1005421
Imaz, Arkaitz; Martinez-Picado, Javier; Niubó, Jordi et al. (2016) HIV-1-RNA Decay and Dolutegravir Concentrations in Semen of Patients Starting a First Antiretroviral Regimen. J Infect Dis 214:1512-1519
Honeycutt, Jenna B; Wahl, Angela; Baker, Caroline et al. (2016) Macrophages sustain HIV replication in vivo independently of T cells. J Clin Invest 126:1353-66
Tokarev, Andrey; Stoneham, Charlotte; Lewinski, Mary K et al. (2016) Pharmacologic Inhibition of Nedd8 Activation Enzyme Exposes CD4-Induced Epitopes within Env on Cells Expressing HIV-1. J Virol 90:2486-502
Victor Garcia, J (2016) Humanized mice for HIV and AIDS research. Curr Opin Virol 19:56-64
Smith, Davey M; Nakazawa, Masato; Freeman, Michael L et al. (2016) Asymptomatic CMV Replication During Early Human Immunodeficiency Virus (HIV) Infection Is Associated With Lower CD4/CD8 Ratio During HIV Treatment. Clin Infect Dis 63:1517-1524
Gianella, Sara; Anderson, Christy M; Var, Susanna R et al. (2016) Replication of Human Herpesviruses Is Associated with Higher HIV DNA Levels during Antiretroviral Therapy Started at Early Phases of HIV Infection. J Virol 90:3944-52
Garcia, J Victor (2016) In vivo platforms for analysis of HIV persistence and eradication. J Clin Invest 126:424-31
Lee, Sook-Kyung; Zhou, Shuntai; Baldoni, Pedro L et al. (2016) Quantification of the Latent HIV-1 Reservoir Using Ultra Deep Sequencing and Primer ID In A Viral Outgrowth Assay. J Acquir Immune Defic Syndr :
Wagner, Gabriel A; Chaillon, Antoine; Liu, Siqi et al. (2016) HIV-associated neurocognitive disorder is associated with HIV-1 dual infection. AIDS 30:2591-2597

Showing the most recent 10 out of 187 publications