The proposed studies use a novel experimental model of viral latency and reactivation that utilizes primary memory cells as targets. Using this system, we plan to understand in detail the mechanisms that HIV-1 uses to establish latency in vivo, as well as the physiological signals that trigger viral reactivation. Knowledge from these areas will be applicable in future translational studies that will seek compounds mimicking or antagonizing the relevant signaling pathways, with the ultimate goal of destroying the latent reservoir.

Public Health Relevance

HIV-1 in infected individuals establishes a relatively small, but long-lived reservoir of latently infected cells. Latent infection is associated with low or no viral gene expression and, accordingly, appears to be non-cytopathic. Latent viruses can undergo reactivation, giving rise to new productive infections that carry full pathogenic potential. The cell type that harbors this long-lived, latent viral reservoir is thought to consist of quiescent memory T cells. We present a novel ex-vivo model for the study HIV latency as well as its reactivation. This model faithfully recapitulates salient features of the in vivo latent reservoir. For example, latent proviruses in this system are devoid of any detectable gene expression, yet, they are perfectly competent for gene expression when reactivated by a number of external stimuli. This model uses primary, human CD4+ lymphocytes and viral integration is polyclonal. This powerful, yet straighforward experimental system will allow us to (i) assess the relative permissivenes of various CD4+ T cell subsets to harbor latent proviruses;(ii) explore signaling pathways that may preclude the establishment of latent infections and/or induce reactivation of latent proviruses;and (iii) explore the use of select agonists and antagonists of the relevant signaling pathways to experimentally manipulate latency and reactivation. Ultimately, HIV-1 eradication will require a profound understanding of the biological processes that control entry and exit from latency.

National Institute of Health (NIH)
Research Project (R01)
Project #
Application #
Study Section
AIDS Molecular and Cellular Biology Study Section (AMCB)
Program Officer
Lawrence, Diane M
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of Utah
Schools of Medicine
Salt Lake City
United States
Zip Code
Cassiday, Patrick A; DePaula-Silva, Ana B; Chumley, Jeffrey et al. (2015) Understanding the molecular manipulation of DCAF1 by the lentiviral accessory proteins Vpr and Vpx. Virology 476:19-25
Gavegnano, Christina; Detorio, Mervi; Montero, Catherine et al. (2014) Ruxolitinib and tofacitinib are potent and selective inhibitors of HIV-1 replication and virus reactivation in vitro. Antimicrob Agents Chemother 58:1977-86
Bonczkowski, Pawel; De Spiegelaere, Ward; Bosque, Alberto et al. (2014) Replication competent virus as an important source of bias in HIV latency models utilizing single round viral constructs. Retrovirology 11:70
Ramirez, Peter W; Famiglietti, Marylinda; Sowrirajan, Bharatwaj et al. (2014) Downmodulation of CCR7 by HIV-1 Vpu results in impaired migration and chemotactic signaling within CD4? T cells. Cell Rep 7:2019-30
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
Budhiraja, Sona; Famiglietti, Marylinda; Bosque, Alberto et al. (2013) Cyclin T1 and CDK9 T-loop phosphorylation are downregulated during establishment of HIV-1 latency in primary resting memory CD4+ T cells. J Virol 87:1211-20
Sherrill-Mix, Scott; Lewinski, Mary K; Famiglietti, Marylinda et al. (2013) HIV latency and integration site placement in five cell-based models. Retrovirology 10:90
Wolschendorf, Frank; Bosque, Alberto; Shishido, Takao et al. (2012) Kinase control prevents HIV-1 reactivation in spite of high levels of induced NF-ýýB activity. J Virol 86:4548-58
Bosque, Alberto; Famiglietti, Marylinda; Weyrich, Andrew S et al. (2011) Homeostatic proliferation fails to efficiently reactivate HIV-1 latently infected central memory CD4+ T cells. PLoS Pathog 7:e1002288
Bosque, Alberto; Planelles, Vicente (2011) Studies of HIV-1 latency in an ex vivo model that uses primary central memory T cells. Methods 53:54-61