Nearly one third of HIV-infected individuals develop neurocognitive deficits despite adequate cART and excellent virological control in the blood. This range of neurocognitive deficits is collectively referred to as HIV-1-associated neurocognitive disorders (HAND). Virus may also enter the brain again in the later stages of infection when there is a general immune failure. The ability of the virus to replicate depends on the cell type and its state of activation. Once inside the brain parenchyma, it resides in perivascular macrophages and microglial cells that provide the site of productive replication and evolution for HIV. Recent studies suggest that there is a substantial viral load in the meninges as well where there is a rich collection of macrophages. Within these regions, HIV infects the macrophages/microglia and astrocytes most commonly located in the perivascular regions where they constitute the blood-brain barrier. Perivascular and meningeal macrophages have been shown to be sites of active viral replication in the human brain. Exosomes are membrane-bound vesicles produced by a variety of cells that contain classical membrane marker proteins such as tetraspanins, adhesion proteins and metalloproteinases. They are considered to play an important role in intercellular communication either by target cell uptake or by inducing cell signaling via membrane receptors. In addition to membrane proteins, exosomes carry mRNAs as well as non-coding RNAs, including miRNAs that are thought to affect gene regulation in the target cells. Research by our group and others has shown that HIV-1-infected cells produce exosomes that activate nave target cells through a dsRNA called TAR. Our long term goal is to understand the role played by exosomes originating from HIV-1 infected cells in regulating host-virus interactions. We hypothesize that unique viral RNA present in the exosomes of infected cells will alter recipient cells impacting regulation of gene expression and establishment of inflammatory response.
Our aims i nclude: To characterize the biogenesis and function of exosomes from infected donor cells under cART (Aim I); To characterize exosomes from infected cells treated with inhibitors and their cellular origin (Aim II), and defining the mechanim of TAR effect on TLR modulation and cytokine production in recipient cells. Collectively our data indicates that infected cells under cART still secrete TAR associated exosmes and that these exosomes activate the nave recipient cells resulting in unwanted proinflammatory signals. These activities will be reversed with use of inhibitors and tested in both an in vitro BBB model and humanized latent model of HIV infection.

Public Health Relevance

Nearly one third of HIV-infected individuals develop neurocognitive deficits despite adequate cART and excellent virological control in the blood. We believe this may be because infected latent cells secrete exosomes that contain parts of the viral RNA. Specifically dsTAR RNA activates NFkB in recipient cells and increase cytokine expression seen in AIDS patients that have neurocognitive deficits.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
1R01NS099029-01
Application #
9136536
Study Section
Special Emphasis Panel (ZRG1)
Program Officer
Wong, May
Project Start
2016-04-01
Project End
2021-03-31
Budget Start
2016-04-01
Budget End
2017-03-31
Support Year
1
Fiscal Year
2016
Total Cost
Indirect Cost
Name
George Mason University
Department
Public Health & Prev Medicine
Type
Schools of Arts and Sciences
DUNS #
077817450
City
Fairfax
State
VA
Country
United States
Zip Code
22030
DeMarino, Catherine; Pleet, Michelle L; Cowen, Maria et al. (2018) Antiretroviral Drugs Alter the Content of Extracellular Vesicles from HIV-1-Infected Cells. Sci Rep 8:7653
Haque, Sanjana; Sinha, Namita; Ranjit, Sabina et al. (2017) Monocyte-derived exosomes upon exposure to cigarette smoke condensate alter their characteristics and show protective effect against cytotoxicity and HIV-1 replication. Sci Rep 7:16120
Poveda, Eva; Freeman, Michael L (2017) Hot News: Exosomes as New Players in HIV Pathogenesis - New Data from the IAS 2017. AIDS Rev 19:173-175
Ojha, Chet Raj; Lapierre, Jessica; Rodriguez, Myosotys et al. (2017) Interplay between Autophagy, Exosomes and HIV-1 Associated Neurological Disorders: New Insights for Diagnosis and Therapeutic Applications. Viruses 9:
DeMarino, Catherine; Schwab, Angela; Pleet, Michelle et al. (2017) Biodegradable Nanoparticles for Delivery of Therapeutics in CNS Infection. J Neuroimmune Pharmacol 12:31-50
Barclay, Robert A; Schwab, Angela; DeMarino, Catherine et al. (2017) Exosomes from uninfected cells activate transcription of latent HIV-1. J Biol Chem 292:11682-11701
Sampey, Gavin C; Saifuddin, Mohammed; Schwab, Angela et al. (2016) Exosomes from HIV-1-infected Cells Stimulate Production of Pro-inflammatory Cytokines through Trans-activating Response (TAR) RNA. J Biol Chem 291:1251-66
Ahsan, Noor A; Sampey, Gavin C; Lepene, Ben et al. (2016) Presence of Viral RNA and Proteins in Exosomes from Cellular Clones Resistant to Rift Valley Fever Virus Infection. Front Microbiol 7:139
Anderson, Monique R; Kashanchi, Fatah; Jacobson, Steven (2016) Exosomes in Viral Disease. Neurotherapeutics 13:535-46
Pleet, Michelle L; Mathiesen, Allison; DeMarino, Catherine et al. (2016) Ebola VP40 in Exosomes Can Cause Immune Cell Dysfunction. Front Microbiol 7:1765

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