Bryostatin-1 decreases HIV-1 infection and viral production in human primary macrophages

2021 ◽  
Author(s):  
Laurent Hany ◽  
Marc-Olivier Turmel ◽  
Corinne Barat ◽  
Michel Ouellet ◽  
Michel J. Tremblay

While combination antiretroviral therapy maintains undetectable viremia in People Living With HIV (PLWH), a life-long treatment is necessary to prevent viremic rebound after therapy cessation. This rebound seemed mainly caused by long lived HIV-1 latently infected cells reversing to a viral productive status. Reversing latency and elimination of these cells by the so-called shock and kill strategy is one of the main investigated leads to achieve an HIV-1 cure. Small molecules referred as latency reversal agents (LRAs) proved to efficiently reactivate latent CD4 + T cells. However, LRAs impact on de novo infection or HIV-1 production in productively infected macrophages remain elusive. Nontoxic doses of bryostatin-1, JQ1 and romidepsin were investigated in human monocyte-derived macrophages (MDMs). Treatment with bryostatin-1 or romidepsin resulted in a downregulation of CD4 and CCR5 receptors respectively, accompanied by a reduction of R5 tropic virus infection. HIV-1 replication was mainly regulated by receptor modulation for bryostatin-1, while romidepsin effect rely on upregulation of SAMHD1 activity. LRA stimulation of chronically infected cells did not enhance neither HIV-1 production nor gene expression. Surprisingly, bryostatin-1 caused a major decrease in viral production. This effect was not viral strain specific but appears to occur only in myeloid cells. Bryostatin-1 treatment of infected MDMs led to decreased amounts of capsid and matrix mature proteins with little to no modulation of precursors. Our observations revealed that bryostatin-1-treated myeloid and CD4 + T cells are responding differently upon HIV-1 infection. Therefore, additional studies are warranted to more fully assess the efficiency of HIV-1 eradicating strategies. Importance HIV-1 persists in a cellular latent form despite therapy that quickly propagates infection upon treatment interruption. Reversing latency would contribute to eradicate these cells, closing a gap to a cure. Macrophages are an acknowledged HIV-1 reservoir during therapy and are suspected to harbor latency establishment in vivo . Yet, the impact of latency reversal agents (LRAs) on HIV-1 infection and viral production in human macrophages is poorly known but nonetheless crucial to probe the safety of this strategy. In this in vitro study, we discovered encouraging anti-replicative features of distinct LRAs in human macrophages. We also described a new viral production inhibition mechanism by protein kinase C agonists which is specific to myeloid cells. This study provides new insights on HIV-1 propagation restriction potentials by LRAs in human macrophages and underline the importance of assessing latency reversal strategy on all HIV-1 targeted cells.

2019 ◽  
Author(s):  
Mateusz Stoszko ◽  
Abdullah M.S. Al-Hatmi ◽  
Anton Skriba ◽  
Michael Roling ◽  
Enrico Ne ◽  
...  

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.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Shringar Rao ◽  
Cynthia Lungu ◽  
Raquel Crespo ◽  
Thijs H. Steijaert ◽  
Alicja Gorska ◽  
...  

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.


2021 ◽  
Author(s):  
Jeffrey Kuniholm ◽  
Elise Armstrong ◽  
Brandy Bernabe ◽  
Carolyn Coote ◽  
Anna Berenson ◽  
...  

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.


2017 ◽  
Vol 91 (6) ◽  
Author(s):  
Caroline Pereira Bittencourt Passaes ◽  
Timothée Bruel ◽  
Jérémie Decalf ◽  
Annie David ◽  
Mathieu Angin ◽  
...  

ABSTRACT The existence of HIV reservoirs in infected individuals under combined antiretroviral therapy (cART) represents a major obstacle toward cure. Viral reservoirs are assessed by quantification of HIV nucleic acids, a method which does not discriminate between infectious and defective viruses, or by viral outgrowth assays, which require large numbers of cells and long-term cultures. Here, we used an ultrasensitive p24 digital assay, which we report to be 1,000-fold more sensitive than classical enzyme-linked immunosorbent assays (ELISAs) in the quantification of HIV-1 Gag p24 production in samples from HIV-infected individuals. Results from ultrasensitive p24 assays were compared to those from conventional viral RNA reverse transcription-quantitative PCR (RT-qPCR)-based assays and from outgrowth assay readout by flow cytometry. Using serial dilutions and flow-based single-cell sorting, we show that viral proteins produced by a single infected cell can be detected by the ultrasensitive p24 assay. This unique sensitivity allowed the early (as soon as day 1 in 43% of cases) and more efficient detection and quantification of p24 in phytohemagglutinin-L (PHA)-stimulated CD4+ T cells from individuals under effective cART. When seven different classes of latency reversal agents (LRA) in resting CD4+ T cells from HIV-infected individuals were tested, the ultrasensitive p24 assay revealed differences in the extent of HIV reactivation. Of note, HIV RNA production was infrequently accompanied by p24 protein production (19%). Among the drugs tested, prostratin showed a superior capacity in inducing viral protein production. In summary, the ultrasensitive p24 assay allows the detection and quantification of p24 produced by single infected CD4+ T cells and provides a unique tool to assess early reactivation of infectious virus from reservoirs in HIV-infected individuals. IMPORTANCE The persistence of HIV reservoirs in infected individuals under effective antiretroviral treatment represents a major obstacle toward cure. Different methods to estimate HIV reservoirs exist, but there is currently no optimal assay to measure HIV reservoirs in HIV eradication interventions. In the present study, we report an ultrasensitive digital ELISA platform for quantification of the HIV-1 protein p24. This method was employed to assess the early reactivation of infectious virus from reservoirs in HIV-1-infected individuals. We found that viral proteins produced by a single infected cell can be detected by an ultrasensitive p24 assay. This unprecedented resolution showed major advantages in comparison to other techniques currently used to assess viral replication in reactivation studies. In addition, such a highly sensitive assay allows discrimination of drug-induced reactivation of productive HIV based on protein expression. The present study heralds new opportunities to evaluate the HIV reservoir and the efficacy of drugs used to target it.


2020 ◽  
Vol 8 (10) ◽  
pp. 1505
Author(s):  
Antonio Victor Campos Coelho ◽  
Ronald Rodrigues de Moura ◽  
Sergio Crovella

The human immunodeficiency virus (HIV-1) causes a progressive depletion of CD4+ T cells, hampering immune function. Current experimental strategies to fight the virus focus on the reactivation of latent HIV-1 in the viral reservoir to make the virus detectable by the immune system, by searching for latency reversal agents (LRAs). We hypothesize that if common molecular pathways elicited by the presence of LRAs are known, perhaps new, more efficient, “shock-and-kill” strategies can be found. Thus, the objective of the present study is to re-evaluate RNA-Seq assays to find differentially expressed genes (DEGs) during latency reversal via transcriptome analysis. We selected six studies (45 samples altogether: 16 negative controls and 29 LRA-treated CD4+ T cells) and 11 LRA strategies through a systematic search in Gene Expression Omnibus (GEO) and PubMed databases. The raw reads were trimmed, counted, and normalized. Next, we detected consistent DEGs in these independent experiments. AZD5582, romidepsin, and suberanilohydroxamic acid (SAHA) were the LRAs that modulated most genes. We detected 948 DEGs shared by those three LRAs. Gene ontology analysis and cross-referencing with other sources of the literature showed enrichment of cell activation, differentiation and signaling, especially mitogen-activated protein kinase (MAPK) and Rho-GTPases pathways.


Viruses ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1451
Author(s):  
Georges Khoury ◽  
Deanna A. Kulpa ◽  
Matthew S. Parsons

An impediment to curing HIV-1 infection is the persistence of latently infected cells in ART-treated people living with HIV (PLWH). A key strategy for curing HIV-1 infection is to activate transcription and translation of latent virus using latency reversing agents (LRAs) and eliminate cells harboring reactivated virus via viral cytopathic effect or immune clearance. In this review, we provide an overview of available LRAs and their use in clinical trials. Furthermore, we describe recent data suggesting that CD8+ T cells promote HIV-1 latency in the context of ART, even in the presence of LRAs, which might at least partially explain the clinical inefficiency of previous “shock and kill” trials. Here, we propose a novel cure strategy called “unlock, shock, disarm, and kill”. The general premise of this strategy is to shut down the pro-latency function(s) of CD8+ T cells, use LRAs to reverse HIV-1 latency, counteract anti-apoptotic molecules, and engage natural killer (NK) cells to mediate the killing of cells harboring reactivated latent HIV-1.


2020 ◽  
Author(s):  
Shringar Rao ◽  
Cynthia Lungu ◽  
Thijs H. Steijaert ◽  
Raquel Crespo ◽  
Robert-Jan Palstra ◽  
...  

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 DEAD-box polypeptide 3, X-Linked (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; pharmacological targeting of DDX3 reversed HIV-1 latency and selectively induced apoptosis in viral RNA-expressing CD4+ T cells from PLWHIV but not bystander cells. DDX3 inhibitor treatment of CD4+ T cells from PLWHIV in an in vitro culture model over five days resulted in an approximately 30% reduction of the inducible latent HIV-1 reservoir as determined by quantitation of CA HIV-1 RNA, by TILDA, as well as by FISH-Flow technology. RNA sequencing analysis revealed that while overall gene expression was minimally dysregulated, treatment of independent donor CD4+ T cells with DDX3 inhibitors led to significant downregulation of BIRC5 and HSPB1A, genes critical to cell survival during HIV-1 infection, providing mechanism for the observed selective cell death. Our data support the translation of DDX3 inhibitor class compounds into HIV-1 curative strategies and provide proof of concept for pharmacological reversal of latency coupled to induction of apoptosis towards elimination of the inducible reservoir.


2018 ◽  
Vol 62 (11) ◽  
Author(s):  
Adam M. Spivak ◽  
Racheal A. Nell ◽  
Mark Petersen ◽  
Laura Martins ◽  
Paul Sebahar ◽  
...  

ABSTRACT Antiretroviral therapy (ART) does not cure HIV-1 infection due to the persistence of proviruses in long-lived resting T cells. Strategies targeting these latently infected cells will be necessary to eradicate HIV-1 in infected individuals. Protein kinase C (PKC) activation is an effective mechanism to reactivate latent proviruses and allows for recognition and clearance of infected cells by the immune system. Several ingenol compounds, naturally occurring PKC agonists, have been described to have potent latency reversal activity. We sought to optimize this activity by synthesizing a library of novel ingenols via esterification of the C-3 hydroxyl group of the ingenol core, which itself is inactive for latency reversal. Newly synthesized ingenol derivatives were evaluated for latency reversal activity, cellular activation, and cytotoxicity alongside commercially available ingenols (ingenol-3,20-dibenzoate, ingenol 3-hexanoate, and ingenol-3-angelate) in HIV latency cell lines and resting CD4+ T cells from aviremic participants. Among the synthetic ingenols that we produced, we identified several compounds that demonstrate high efficacy and represent promising leads as latency reversal agents for HIV-1 eradication.


1997 ◽  
Vol 185 (1) ◽  
pp. 55-64 ◽  
Author(s):  
Andrew D. Badley ◽  
David Dockrell ◽  
Margaret Simpson ◽  
Ron Schut ◽  
David H. Lynch ◽  
...  

Apoptosis of bystander uninfected CD4+ T lymphocytes by neighboring HIV-infected cells is observed in cell culture and in lymphoid tissue of HIV-infected individuals. This study addresses whether antigen-presenting cells such as human macrophages mediate apoptosis of CD4+ T cells from HIV-infected individuals. Uninfected human macrophages, and to a larger degree, HIV-infected macrophages mediate apoptosis of T cells from HIV-infected, but not from uninfected control individuals. This macrophage-dependent killing targets CD4+, but not CD8+ T lymphocytes from HIV-infected individuals, and direct contact between macrophages and lymphocytes is required. Additional analyses indicated that the apoptosis-inducing ligands, FasL and tumor necrosis factor (TNF), mediate this macrophage-induced apoptosis of CD4+ T cells. These results support a role for macrophage-associated FasL and TNF in the selective depletion of CD4+ T cells in HIV-infected individuals.


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