scholarly journals Exosomes from Nef expressing monocytic cells restrict HIV-1 replication in infected cells through the assembly of stress granules

2017 ◽  
Author(s):  
Mohammad Yunus Ansari ◽  
Hasan Imam ◽  
Nishant Kumar ◽  
Zulfazal Ahmed ◽  
Shahid Jameel
Keyword(s):  
T Cells ◽  
Cd4 T Cells ◽  
Virus Production ◽  
Stress Granules ◽  
Monocytic Cells ◽  
Activation Induced Cell Death ◽  
Arginine Residues ◽  
Infected Cells ◽  
Almost All ◽  
Hiv 1

AbstractExosomes are membranous vesicles secreted from almost all types of cells, carry proteins and nucleic acids and function as vehicles for intercellular communication. Cells infected with HIV-1 or expressing the viral Nef protein secrete more exosomes than uninfected cells or those not expressing this protein. We used stably transfected, Nef-expressing U937 human monocytic cells and exosomes purified from these cells to study their effects on HIV-1 infected and uninfected CD4+ T-cells. The Nef exosomes inhibited virus production from HIV-1 infected CD4+ T-cells, but caused activation induced cell death in uninfected bystander cells. Mutations in its conserved Arginine residues and in the secretion-modification-region failed to secrete Nef into exosomes. Cell lines expressing these mutant Nef proteins did not deliver it to the target CD4+ T-cells, and exosomes prepared from these mutant Nef-expressing cells also did not inhibit virus production. Nef exosomes inhibited virus production by inducing the assembly of stress granules in HIV-1 infected cells, which sequestered increased amounts of gag mRNA. This is a novel mechanism wherein we show the effects of exosomes on the assembly of stress granules and viral translational repression.

scholarly journals HIV-1 Infection Transcriptomics: Meta-Analysis of CD4+ T Cells Gene Expression Profiles

Viruses ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 244 ◽  
Author(s):  
Antonio Victor Campos Coelho ◽  
Rossella Gratton ◽  
João Paulo Britto de Melo ◽  
José Leandro Andrade-Santos ◽  
Rafael Lima Guimarães ◽  
...  
Keyword(s):  
Gene Expression ◽  
T Cells ◽  
Differentially Expressed Genes ◽  
Cd4 T Cells ◽  
Expression Profiles ◽  
Meta Analysis ◽  
Differentially Expressed ◽  
Rna Seq ◽  
Infected Cells ◽  
Hiv 1

HIV-1 infection elicits a complex dynamic of the expression various host genes. High throughput sequencing added an expressive amount of information regarding HIV-1 infections and pathogenesis. RNA sequencing (RNA-Seq) is currently the tool of choice to investigate gene expression in a several range of experimental setting. This study aims at performing a meta-analysis of RNA-Seq expression profiles in samples of HIV-1 infected CD4+ T cells compared to uninfected cells to assess consistently differentially expressed genes in the context of HIV-1 infection. We selected two studies (22 samples: 15 experimentally infected and 7 mock-infected). We found 208 differentially expressed genes in infected cells when compared to uninfected/mock-infected cells. This result had moderate overlap when compared to previous studies of HIV-1 infection transcriptomics, but we identified 64 genes already known to interact with HIV-1 according to the HIV-1 Human Interaction Database. A gene ontology (GO) analysis revealed enrichment of several pathways involved in immune response, cell adhesion, cell migration, inflammation, apoptosis, Wnt, Notch and ERK/MAPK signaling.

scholarly journals Similar frequency and inducibility of intact HIV-1 proviruses in blood and lymph nodes

2020 ◽  
Author(s):  
Alyssa R Martin ◽  
Alexandra M Bender ◽  
Jada Hackman ◽  
Kyungyoon J Kwon ◽  
Briana A Lynch ◽  
...  
Keyword(s):  
T Cells ◽  
Lymph Nodes ◽  
Cd4 T Cells ◽  
Viral Rna ◽  
Latent Reservoir ◽  
Similar Frequency ◽  
Latently Infected ◽  
Infected Cells ◽  
Secondary Lymphoid Organs ◽  
Hiv 1

Abstract Background The HIV-1 latent reservoir (LR) in resting CD4 + T cells is a barrier to cure. LR measurements are commonly performed on blood samples and therefore may miss latently infected cells residing in tissues, including lymph nodes. Methods We determined the frequency of intact HIV-1 proviruses and proviral inducibility in matched peripheral blood (PB) and lymph node (LN) samples from ten HIV-1-infected patients on ART using the intact proviral DNA assay and a novel quantitative viral induction assay. Prominent viral sequences from induced viral RNA were characterized using a next-generation sequencing assay. Results The frequencies of CD4 + T cells with intact proviruses were not significantly different in PB vs LN (61vs104/10 6CD4 + cells), and were substantially lower than frequencies of CD4 + T cells with defective proviruses. The frequencies of CD4 + T cells induced to produce high levels of viral RNA were not significantly different in PB vs LN (4.3/10 6 vs 7.9/10 6), but were 14-fold lower than the frequencies of cells with intact proviruses. Sequencing of HIV-1 RNA from induced proviruses revealed comparable sequences in paired PB and LN samples. Conclusions These results further support the use of PB as an appropriate proxy for the HIV-1 LR in secondary lymphoid organs

scholarly journals Th1/17 Polarization of CD4 T Cells Supports HIV-1 Persistence during Antiretroviral Therapy

2015 ◽  
Vol 89 (22) ◽  
pp. 11284-11293 ◽  
Author(s):  
Hong Sun ◽  
Dhohyung Kim ◽  
Xiaodong Li ◽  
Maja Kiselinova ◽  
Zhengyu Ouyang ◽  
...  
Keyword(s):  
T Cells ◽  
Antiretroviral Therapy ◽  
Cd4 T Cells ◽  
Ex Vivo ◽  
Memory Cell ◽  
Viral Reservoir ◽  
Target Cells ◽  
Infected Cells ◽  
Hiv 1

ABSTRACTThe ability to persist long term in latently infected CD4 T cells represents a characteristic feature of HIV-1 infection and the predominant barrier to efforts aiming at viral eradication and cure. Yet, increasing evidence suggests that only small subsets of CD4 T cells with specific developmental and maturational profiles are able to effectively support HIV-1 long-term persistence. Here, we analyzed how the functional polarization of CD4 T cells shapes and structures the reservoirs of HIV-1-infected cells. We found that CD4 T cells enriched for a Th1/17 polarization had elevated susceptibilities to HIV-1 infection inex vivoassays, harbored high levels of HIV-1 DNA in persons treated with antiretroviral therapy, and made a disproportionately increased contribution to the viral reservoir relative to their contribution to the CD4 T memory cell pool. Moreover, HIV-1 DNA levels in Th1/17 cells remained stable over many years of antiretroviral therapy, resulting in a progressively increasing contribution of these cells to the viral reservoir, and phylogenetic studies suggested preferential long-term persistence of identical viral sequences during prolonged antiretroviral treatment in this cell compartment. Together, these data suggest that Th1/17 CD4 T cells represent a preferred site for HIV-1 DNA long-term persistence in patients receiving antiretroviral therapy.IMPORTANCECurrent antiretroviral therapy is very effective in suppressing active HIV-1 replication but does not fully eliminate virally infected cells. The ability of HIV-1 to persist long term despite suppressive antiretroviral combination therapy represents a perplexing aspect of HIV-1 disease pathogenesis, since most HIV-1 target cells are activated, short-lived CD4 T cells. This study suggests that CD4 T helper cells with Th1/17 polarization have a preferential role as a long-term reservoir for HIV-1 infection during antiretroviral therapy, possibly because these cells may imitate some of the functional properties traditionally attributed to stem cells, such as the ability to persist for extremely long periods of time and to repopulate their own pool size through homeostatic self-renewal. These observations support the hypothesis that HIV-1 persistence is driven by small subsets of long-lasting stem cell-like CD4 T cells that may represent particularly promising targets for clinical strategies aiming at HIV-1 eradication and cure.

scholarly journals Chromatin maturation of the HIV-1 provirus in primary resting CD4+ T cells

2019 ◽  
Author(s):  
Birgitta Lindqvist ◽  
Sara Svensson Akusjarvi ◽  
Anders Sonnerborg ◽  
Marios Dimitriou ◽  
J. Peter Svensson
Keyword(s):  
T Cells ◽  
T Cell Activation ◽  
Cd4 T Cells ◽  
Cell Activation ◽  
Ex Vivo ◽  
Immunodeficiency Virus ◽  
Latently Infected ◽  
Infected Cells ◽  
Active Transcription ◽  
Hiv 1

Human immunodeficiency virus type 1 (HIV-1) infection is a chronic condition, where viral DNA integrates into the genome. Latently infected cells form a persistent, heterogeneous reservoir. The reservoir that reinstates an active replication comprises only cells with intact provirus that can be reactivated. We confirmed that latently infected cells from patients exhibited active transcription throughout the provirus. To find transcriptional determinants, we characterized the establishment and maintenance of viral latency during proviral chromatin maturation in cultures of primary CD4+ T-cells for four months after ex vivo HIV-1 infection. As heterochromatin (marked with H3K9me3 or H3K27me3) gradually stabilized, the provirus became less accessible with reduced activation potential. In a subset of infected cells, active marks (i.e., H3K27ac) remained detectable, even after prolonged proviral silencing. After T-cell activation, the proviral activation occurred uniquely in cells with H3K27ac-marked proviruses. Our observations suggested that, after transient proviral activation, cells were actively returned to latency.

scholarly journals Gliotoxin, identified from a screen of fungal metabolites, disrupts 7SK snRNP, releases P-TEFb and reverses HIV-1 latency

2019 ◽  
Author(s):  
Mateusz Stoszko ◽  
Abdullah M.S. Al-Hatmi ◽  
Anton Skriba ◽  
Michael Roling ◽  
Enrico Ne ◽  
...  
Keyword(s):  
Gene Expression ◽  
Mass Spectrometry ◽  
T Cells ◽  
Cd4 T Cells ◽  
Ex Vivo ◽  
Reversal Agents ◽  
Latently Infected ◽  
Infected Cells ◽  
Therapeutic Compounds ◽  
Hiv 1

AbstractA leading pharmacological strategy towards HIV cure requires “shock” or activation of HIV gene expression in latently infected cells with Latency Reversal Agents (LRAs) followed by their subsequent clearance. In a screen for novel LRAs we used fungal secondary metabolites (extrolites) as a source of bio-active molecules. Using orthogonal mass spectrometry (MS) coupled to latency reversal bioassays, we identified gliotoxin (GTX) as a novel LRA. GTX significantly induced HIV-1 gene expression in latent ex vivo infected primary cells and in CD4+ T cells from all aviremic HIV-1+ participants. RNA sequencing identified 7SK RNA, the scaffold of the P-TEFb inhibitory 7SK snRNP complex to be significantly reduced upon GTX treatment of independent donor CD4+T cells. GTX disrupted 7SK snRNP, releasing active P-TEFb, which then phosphorylated RNA Pol II CTD, inducing HIV transcription. Our data highlight the power of combining a medium throughput bioassay, mycology and orthogonal mass spectrometry to identify novel potentially therapeutic compounds.

scholarly journals Naive CD4+ T Cells Harbor a Large Inducible Reservoir of Latent, Replication-competent Human Immunodeficiency Virus Type 1

2019 ◽  
Vol 69 (11) ◽  
pp. 1919-1925 ◽  
Author(s):  
Jennifer M Zerbato ◽  
Deborah K McMahon ◽  
Michelle D Sobolewski ◽  
John W Mellors ◽  
Nicolas Sluis-Cremer
Keyword(s):  
Human Immunodeficiency Virus ◽  
T Cells ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Cd4 T Cells ◽  
Virus Production ◽  
Major Barrier ◽  
Immunodeficiency Virus ◽  
Hiv 1

Abstract Background The latent human immunodeficiency virus type 1 (HIV-1) reservoir represents a major barrier to a cure. Based on the levels of HIV-1 DNA in naive (TN) vs resting memory CD4+ T cells, it is widely hypothesized that this reservoir resides primarily within memory cells. Here, we compared virus production from TN and central memory (TCM) CD4+ T cells isolated from HIV-1–infected individuals on suppressive therapy. Methods CD4+ TN and TCM cells were purified from the blood of 7 HIV-1–infected individuals. We quantified total HIV-1 DNA in the CD4+ TN and TCM cells. Extracellular virion-associated HIV-1 RNA or viral outgrowth assays were used to assess latency reversal following treatment with anti-CD3/CD28 monoclonal antibodies (mAbs), phytohaemagglutinin/interleukin-2, phorbol 12-myristate 13-acetate/ionomycin, prostratin, panobinostat, or romidepsin. Results HIV-1 DNA was significantly higher in TCM compared to TN cells (2179 vs 684 copies/106 cells, respectively). Following exposure to anti-CD3/CD28 mAbs, virion-associated HIV-1 RNA levels were similar between TCM and TN cells (15 135 vs 18 290 copies/mL, respectively). In 4/7 donors, virus production was higher for TN cells independent of the latency reversing agent used. Replication-competent virus was recovered from both TN and TCM cells. Conclusions Although the frequency of HIV-1 infection is lower in TN compared to TCM cells, as much virus is produced from the TN population after latency reversal. This finding suggests that quantifying HIV-1 DNA alone may not predict the size of the inducible latent reservoir and that TN cells may be an important reservoir of latent HIV-1.

scholarly journals Apobec3A maintains HIV-1 latency through recruitment of epigenetic silencing machinery to the long terminal repeat

2019 ◽  
Vol 116 (6) ◽  
pp. 2282-2289 ◽  
Author(s):  
Manabu Taura ◽  
Eric Song ◽  
Ya-Chi Ho ◽  
Akiko Iwasaki
Keyword(s):  
T Cells ◽  
Long Terminal Repeat ◽  
Cd4 T Cells ◽  
Terminal Repeat ◽  
Target Cells ◽  
Mrna Editing ◽  
Latently Infected ◽  
Infected Cells ◽  
Editing Enzyme ◽  
Hiv 1

HIV-1 integrates into the genome of target cells and establishes latency indefinitely. Understanding the molecular mechanism of HIV-1 latency maintenance is needed for therapeutic strategies to combat existing infection. In this study, we found an unexpected role for Apobec3A (apolipoprotein B MRNA editing enzyme catalytic subunit 3A, abbreviated “A3A”) in maintaining the latency state within HIV-1–infected cells. Overexpression of A3A in latently infected cell lines led to lower reactivation, while knockdown or knockout of A3A led to increased spontaneous and inducible HIV-1 reactivation. A3A maintains HIV-1 latency by associating with proviral DNA at the 5′ long terminal repeat region, recruiting KAP1 and HP1, and imposing repressive histone marks. We show that knockdown of A3A in latently infected human primary CD4 T cells enhanced HIV-1 reactivation. Collectively, we provide evidence and a mechanism by which A3A reinforces HIV-1 latency in infected CD4 T cells.

scholarly journals Ex vivo activation of CD4+ T-cells from donors on suppressive ART can lead to sustained production of infectious HIV-1 from a subset of infected cells

2017 ◽  
Vol 13 (2) ◽  
pp. e1006230 ◽  
Author(s):  
John K. Bui ◽  
Elias K. Halvas ◽  
Elizabeth Fyne ◽  
Michele D. Sobolewski ◽  
Dianna Koontz ◽  
...  
Keyword(s):  
T Cells ◽  
Cd4 T Cells ◽  
Ex Vivo ◽  
Infected Cells ◽  
Hiv 1

scholarly journals Selective cell death in HIV-1-infected cells by DDX3 inhibitors leads to depletion of the inducible reservoir

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Shringar Rao ◽  
Cynthia Lungu ◽  
Raquel Crespo ◽  
Thijs H. Steijaert ◽  
Alicja Gorska ◽  
...  
Keyword(s):  
T Cells ◽  
Cell Death ◽  
Cd4 T Cells ◽  
Viral Rna ◽  
People Living With Hiv ◽  
Infected Cells ◽  
Latent Hiv ◽  
Apoptotic Pathways ◽  
Induced Apoptosis ◽  
Hiv 1

AbstractAn innovative approach to eliminate HIV-1-infected cells emerging out of latency, the major hurdle to HIV-1 cure, is to pharmacologically reactivate viral expression and concomitantly trigger intracellular pro-apoptotic pathways in order to selectively induce cell death (ICD) of infected cells, without reliance on the extracellular immune system. In this work, we demonstrate the effect of DDX3 inhibitors on selectively inducing cell death in latent HIV-1-infected cell lines, primary CD4+ T cells and in CD4+ T cells from cART-suppressed people living with HIV-1 (PLWHIV). We used single-cell FISH-Flow technology to characterise the contribution of viral RNA to inducing cell death. The pharmacological targeting of DDX3 induced HIV-1 RNA expression, resulting in phosphorylation of IRF3 and upregulation of IFNβ. DDX3 inhibition also resulted in the downregulation of BIRC5, critical to cell survival during HIV-1 infection, and selectively induced apoptosis in viral RNA-expressing CD4+ T cells but not bystander cells. DDX3 inhibitor treatment of CD4+ T cells from PLWHIV resulted in an approximately 50% reduction of the inducible latent HIV-1 reservoir by quantitation of HIV-1 RNA, by FISH-Flow, RT-qPCR and TILDA. This study provides proof of concept for pharmacological reversal of latency coupled to induction of apoptosis towards the elimination of the inducible reservoir.

scholarly journals Intragenic proviral elements support transcription of defective HIV-1 proviruses

2021 ◽  
Author(s):  
Jeffrey Kuniholm ◽  
Elise Armstrong ◽  
Brandy Bernabe ◽  
Carolyn Coote ◽  
Anna Berenson ◽  
...  
Keyword(s):  
T Cells ◽  
Cd4 T Cells ◽  
Treatment Interruption ◽  
Regulatory Elements ◽  
Host Cells ◽  
People Living With Hiv ◽  
Latently Infected ◽  
Infected Cells ◽  
Living With Hiv ◽  
Hiv 1

ABSTRACTHIV-establishes a persistent proviral reservoir by integrating into the genome of infected host cells. Current antiretroviral treatments do not target this persistent population of proviruses which include latently infected cells that upon treatment interruption can be reactivated to contribute to HIV-1 rebound. Deep sequencing of persistent HIV proviruses has revealed that greater than 90% of integrated HIV genomes are defective and unable to produce infectious virions. We hypothesized that intragenic elements in the HIV genome support transcription of aberrant HIV-1 RNAs from defective proviruses that lack long terminal repeats (LTRs). Using an intact provirus detection assay, we observed that resting CD4+ T cells and monocyte-derived macrophages (MDMs) are biased towards generating defective HIV-1 proviruses. Multiplex reverse transcription digital drop PCR identified Env and Nef transcripts which lacked 5’ untranslated regions (UTR) in acutely infected CD4+ T cells and MDMs indicating transcripts are generated that do not utilize the promoter within the LTR. 5’UTR-deficient Env transcripts were also identified in a cohort of people living with HIV (PLWH) on ART, suggesting that these aberrant RNAs are produced in vivo. Using 5’ rapid amplification of cDNA ends (RACE), we mapped the start site of these transcripts within the Env gene. This region bound several cellular transcription factors and functioned as a transcriptional regulatory element that could support transcription and translation of downstream HIV-1 RNAs. These studies provide mechanistic insights into how defective HIV-1 proviruses are persistently expressed to potentially drive inflammation in PLWH.Author SummaryPeople living with HIV establish a persistent reservoir which includes latently infected cells that fuel viral rebound upon treatment interruption. However, the majority of HIV-1 genomes in these persistently infected cells are defective. Whether these defective HIV genomes are expressed and whether they contribute to HIV associated diseases including accelerated aging, neurodegenerative symptoms, and cardiovascular diseases are still outstanding questions. In this paper, we demonstrate that acute infection of macrophages and resting T cells is biased towards generating defective viruses which are expressed by DNA regulatory elements in the HIV genome. These studies describe an alternative mechanism for chronic expression of HIV genomes.

Sign in / Sign up

Export Citation Format

Share Document