scholarly journals The XPB Subunit of the TFIIH Complex Plays a Critical Role in HIV-1 Transcription and XPB Inhibition by Spironolactone Prevents HIV-1 Reactivation from Latency

2020 ◽  
Author(s):  
Luisa Mori ◽  
Katharine Jenike ◽  
Yang-Hui Jimmy Yeh ◽  
Benoît Lacombe ◽  
Chuan Li ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Cell Line ◽  
Treatment Interruption ◽  
Viral Reservoir ◽  
Functional Cure ◽  
Hiv Transcription ◽  
Long Term Treatment ◽  
Cellular Transcription ◽  
Hiv 1

HIV transcription requires assembly of cellular transcription factors at the HIV-1promoter. The TFIIH general transcription factor facilitates transcription initiation by opening the DNA strands around the transcription start site and phosphorylating the C-terminal domain for RNA polymerase II (RNAPII) for activation. Spironolactone (SP), an FDA approved aldosterone antagonist, triggers the proteasomal degradation of the XPB subunit of TFIIH, and concurrently suppresses acute HIV infection in vitro. Here we investigated SP as a possible block-and-lock agent for a functional cure aimed at the transcriptional silencing of the viral reservoir. The long-term activity of SP was investigated in primary and cell line models of HIV-1 latency and reactivation. We show that SP rapidly inhibits HIV-1 transcription by reducing RNAPII recruitment to the HIV-1 genome. shRNA knockdown of XPB confirmed XPB degradation as the mechanism of action. Unfortunately, long-term pre-treatment with SP does not result in epigenetic suppression of HIV upon SP treatment interruption, since virus rapidly rebounds when XPB reemerges; however, SP alone without ART maintains the transcriptional suppression. Importantly, SP inhibits HIV reactivation from latency in both cell line models and resting CD4+T cells isolated from aviremic infected individuals upon cell stimulation with latency reversing agents. Furthermore, long-term treatment with concentrations of SP that potently degrade XPB does not lead to global dysregulation of cellular mRNA expression. Overall, these results suggest that XPB plays a key role in HIV transcriptional regulation and XPB degradation by SP strengthens the potential of HIV transcriptional inhibitors in block-and-lock HIV cure approaches. IMPORTANCE Antiretroviral therapy (ART) effectively reduces an individual’s HIV loads to below the detection limit, nevertheless rapid viral rebound immediately ensues upon treatment interruption. Furthermore, virally suppressed individuals experience chronic immune activation from ongoing low-level virus expression. Thus, the importance of identifying novel therapeutics to explore in block-and-lock HIV functional cure approaches, aimed at the transcriptional and epigenetic silencing of the viral reservoir to block reactivation from latency. We investigated the potential of repurposing the FDA-approved spironolactone (SP), as one such drug. SP treatment rapidly degrades a host transcription factor subunit, XPB, inhibiting HIV transcription and blocking reactivation from latency. Long-term SP treatment does not affect cellular viability, cell cycle progression or global cellular transcription. SP alone blocks HIV transcription in the absence of ART but does not delay rebound upon drug removal as XPB rapidly reemerges. This study highlights XPB as a novel drug target in block-and-lock therapeutic approaches.

scholarly journals Immunological markers after long-term treatment interruption in chronically HIV-1 infected patients with CD4 cell count above 400 × 106 cells/l

AIDS ◽  
2005 ◽  
Vol 19 (1) ◽  
pp. 53-61 ◽  
Author(s):  
Rodolphe Thiébaut ◽  
Isabelle Pellegrin ◽  
Geneviève Chêne ◽  
Jean François Viallard ◽  
Hervé Fleury ◽  
...  
Keyword(s):  
Cell Count ◽  
Treatment Interruption ◽  
Term Treatment ◽  
Cd4 Cell Count ◽  
Immunological Markers ◽  
Long Term Treatment ◽  
Cd4 Cell ◽  
Hiv 1

scholarly journals Key Players in HIV-1 Transcriptional Regulation: Targets for a Functional Cure

Viruses ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 529 ◽  
Author(s):  
Luisa Mori ◽  
Susana T. Valente
Keyword(s):  
Integration Site ◽  
Great Part ◽  
Treatment Interruption ◽  
Host Genome ◽  
Viral Reservoir ◽  
Latent Reservoir ◽  
Functional Cure ◽  
Transcript Elongation ◽  
Rna Transcript ◽  
Hiv 1

HIV-1 establishes a life-long infection when proviral DNA integrates into the host genome. The provirus can then either actively transcribe RNA or enter a latent state, without viral production. The switch between these two states is governed in great part by the viral protein, Tat, which promotes RNA transcript elongation. Latency is also influenced by the availability of host transcription factors, integration site, and the surrounding chromatin environment. The latent reservoir is established in the first few days of infection and serves as the source of viral rebound upon treatment interruption. Despite effective suppression of HIV-1 replication by antiretroviral therapy (ART), to below the detection limit, ART is ineffective at reducing the latent reservoir size. Elimination of this reservoir has become a major goal of the HIV-1 cure field. However, aside from the ideal total HIV-1 eradication from the host genome, an HIV-1 remission or functional cure is probably more realistic. The “block-and-lock” approach aims at the transcriptional silencing of the viral reservoir, to render suppressed HIV-1 promoters extremely difficult to reactivate from latency. There are unfortunately no clinically available HIV-1 specific transcriptional inhibitors. Understanding the mechanisms that regulate latency is expected to provide novel targets to be explored in cure approaches.

scholarly journals Impact of a decade of successful antiretroviral therapy initiated at HIV-1 seroconversion on blood and rectal reservoirs

eLife ◽  
2015 ◽  
Vol 4 ◽  
Author(s):  
Eva Malatinkova ◽  
Ward De Spiegelaere ◽  
Pawel Bonczkowski ◽  
Maja Kiselinova ◽  
Karen Vervisch ◽  
...  
Keyword(s):  
Antiretroviral Therapy ◽  
Treatment Initiation ◽  
Cross Sectional Study ◽  
Functional Cure ◽  
Cross Sectional ◽  
Polymerase Chain ◽  
Low Levels ◽  
Rectal Biopsies ◽  
Hiv 1

Persistent reservoirs remain the major obstacles to achieve an HIV-1 cure. Prolonged early antiretroviral therapy (ART) may reduce the extent of reservoirs and allow for virological control after ART discontinuation. We compared HIV-1 reservoirs in a cross-sectional study using polymerase chain reaction-based techniques in blood and tissue of early-treated seroconverters, late-treated patients, ART-naïve seroconverters, and long-term non-progressors (LTNPs) who have spontaneous virological control without treatment. A decade of early ART reduced the total and integrated HIV-1 DNA levels compared with later treatment initiation, but not reaching the low levels found in LTNPs. Total HIV-1 DNA in rectal biopsies did not differ between cohorts. Importantly, lower viral transcription (HIV-1 unspliced RNA) and enhanced immune preservation (CD4/CD8), reminiscent of LTNPs, were found in early compared to late-treated patients. This suggests that early treatment is associated with some immunovirological features of LTNPs that may improve the outcome of future interventions aimed at a functional cure.

A new small-molecule compound, Q308, silences latent HIV-1 provirus by suppressing Tat- and FACT-mediated transcription

2021 ◽  
Author(s):  
Chen-liang Zhou ◽  
Yi-fan Huang ◽  
Yi-bin Li ◽  
Tai-zhen Liang ◽  
Teng-yi Zheng ◽  
...  
Keyword(s):  
Small Molecule ◽  
Difficult Problem ◽  
Viral Reservoir ◽  
Functional Cure ◽  
Latently Infected ◽  
Small Molecule Compound ◽  
Infected Cells ◽  
Latent Hiv ◽  
Anti Hiv ◽  
Hiv 1

Eliminating the latent HIV reservoir remains a difficult problem for creating an HIV functional cure or achieving remission. The “block-and-lock” strategy aims to steadily suppress transcription of the viral reservoir and lock the HIV promoter in deep latency using latency-promoting agents (LPAs). However, to date, most of the investigated LPA candidates are not available for clinical trials, and some of them exhibit immune-related adverse reactions. The discovery and development of new, active, and safe LPA candidates for an HIV cure are necessary to eliminate residual HIV-1 viremia through the “block-and-lock” strategy. In this study, we demonstrated that a new small-molecule compound, Q308, silenced the HIV-1 provirus by inhibiting Tat-mediated gene transcription and selectively downregulating the expression levels of the facilitated chromatin transcription (FACT) complex. Strikingly, Q308 induced the preferential apoptosis in HIV-1 latently infected cells, indicating that Q308 may reduce the size of the viral reservoir and thus further prevent viral rebound. These findings highlight that Q308 is a novel and safe anti-HIV-1 inhibitor candidate for a functional cure.

scholarly journals A minor population of macrophage-tropic HIV-1 variants is identified in recrudescing viremia following analytic treatment interruption

2020 ◽  
Vol 117 (18) ◽  
pp. 9981-9990 ◽  
Author(s):  
Viviane M. Andrade ◽  
Carla Mavian ◽  
Dunja Babic ◽  
Thaissa Cordeiro ◽  
Mark Sharkey ◽  
...  
Keyword(s):  
Treatment Interruption ◽  
Viral Reservoir ◽  
Analytic Treatment ◽  
Recombinant Viruses ◽  
Minor Population ◽  
Clock Analysis ◽  
A Minor ◽  
Molecular Clock Analysis ◽  
Insight Into ◽  
Hiv 1

HIV-1 persists in cellular reservoirs that can reignite viremia if antiretroviral therapy (ART) is interrupted. Therefore, insight into the nature of those reservoirs may be revealed from the composition of recrudescing viremia following treatment cessation. A minor population of macrophage-tropic (M-tropic) viruses was identified in a library of recombinant viruses constructed with individual envelope genes that were obtained from plasma of six individuals undergoing analytic treatment interruption (ATI). M-tropic viruses could also be enriched from post-ATI plasma using macrophage-specific (CD14) but not CD4+ T cell-specific (CD3) antibodies, suggesting that M-tropic viruses had a macrophage origin. Molecular clock analysis indicated that the establishment of M-tropic HIV-1 variants predated ATI. Collectively, these data suggest that macrophages are a viral reservoir in HIV-1–infected individuals on effective ART and that M-tropic variants can appear in rebounding viremia when treatment is interrupted. These findings have implications for the design of curative strategies for HIV-1.

scholarly journals Child–Adult Transition in Sarcoidosis: A Series of 52 Patients

2020 ◽  
Vol 9 (7) ◽  
pp. 2097 ◽  
Author(s):  
Simon Chauveau ◽  
Florence Jeny ◽  
Marie-Emeline Montagne ◽  
Rola Abou Taam ◽  
Véronique Houdouin ◽  
...  
Keyword(s):  
Median Duration ◽  
Severe Disease ◽  
Clinical Information ◽  
Treatment Interruption ◽  
Term Treatment ◽  
Adult Transition ◽  
Long Term Treatment ◽  
Pediatric Onset

(1) Background: Pediatric sarcoidosis is a rare and mostly severe disease. Very few pediatric series with a prolonged follow-up are reported. We aimed to evaluate the evolution of pediatric sarcoidosis in adulthood. (2) Material and methods: Patients over 18-years-old with a pediatric-onset sarcoidosis (≤15-year-old) who completed at least a three-year follow-up in French expert centers were included. Clinical information at presentation and outcome in adulthood were studied. (3) Results: A total of 52 patients were included (34 prospectively in childhood and 18 retrospectively in adulthood), with a mean age of 12 (±2.7) at diagnosis. The median duration time of follow-up was 11.5 years (range 3–44.5). Relapses mostly occurred during treatment decrease (84.5%), others within the three years after treatment interruption (9.1%), and rarely when the disease was stable for more than three years (6.4%). Sarcoidosis was severe in 11 (21.2%) in adulthood. Patients received a high corticosteroid cumulative dose (median 17,900 mg) for a median duration of five years (range 0–32), resulting in mostly mild (18; 35.3%) and rarely severe (2; 3.8%) adverse events. (4) Conclusions: Pediatric-onset sarcoidosis needed a long-term treatment in almost half of the patients. Around one fifth of pediatric-onset sarcoidosis patients had severe sarcoidosis consequences in adulthood.

Structured treatment interruption in chronically HIV-1 infected patients after long-term viral suppression

AIDS ◽  
2000 ◽  
Vol 14 (4) ◽  
pp. 397-403 ◽  
Author(s):  
Lidia Ruiz ◽  
Javier Martinez-Picado ◽  
Joan Romeu ◽  
Roger Paredes ◽  
Mohd Khalil Zayat ◽  
...  
Keyword(s):  
Viral Suppression ◽  
Treatment Interruption ◽  
Hiv 1

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 ZBTB2 represses HIV-1 transcription and is regulated by HIV-1 Vpr and cellular DNA damage responses

2021 ◽  
Vol 17 (2) ◽  
pp. e1009364
Author(s):  
James W. Bruce ◽  
Megan Bracken ◽  
Edward Evans ◽  
Nathan Sherer ◽  
Paul Ahlquist
Keyword(s):  
Gene Expression ◽  
Dna Damage ◽  
Transcription Factor ◽  
Histone Deacetylation ◽  
Transcriptional Elongation ◽  
Cellular Transcription Factor ◽  
Dna Damaging Agents ◽  
Atr Kinase ◽  
Cellular Transcription ◽  
Hiv 1

Previously, we reported that cellular transcription factor ZASC1 facilitates DNA-dependent/RNA-independent recruitment of HIV-1 TAT and the cellular elongation factor P-TEFb to the HIV-1 promoter and is a critical factor in regulating HIV-1 transcriptional elongation (PLoS Path e1003712). Here we report that cellular transcription factor ZBTB2 is a novel repressor of HIV-1 gene expression. ZBTB2 strongly co-immunoprecipitated with ZASC1 and was dramatically relocalized by ZASC1 from the cytoplasm to the nucleus. Mutations abolishing ZASC1/ZBTB2 interaction prevented ZBTB2 nuclear relocalization. We show that ZBTB2-induced repression depends on interaction of cellular histone deacetylases (HDACs) with the ZBTB2 POZ domain. Further, ZASC1 interaction specifically recruited ZBTB2 to the HIV-1 promoter, resulting in histone deacetylation and transcription repression. Depleting ZBTB2 by siRNA knockdown or CRISPR/CAS9 knockout in T cell lines enhanced transcription from HIV-1 vectors lacking Vpr, but not from these vectors expressing Vpr. Since HIV-1 Vpr activates the viral LTR by inducing the ATR kinase/DNA damage response pathway, we investigated ZBTB2 response to Vpr and DNA damaging agents. Expressing Vpr or stimulating the ATR pathway with DNA damaging agents impaired ZASC1’s ability to localize ZBTB2 to the nucleus. Moreover, the effects of DNA damaging agents and Vpr on ZBTB2 localization could be blocked by ATR kinase inhibitors. Critically, Vpr and DNA damaging agents decreased ZBTB2 binding to the HIV-1 promoter and increased promoter histone acetylation. Thus, ZBTB2 is recruited to the HIV-1 promoter by ZASC1 and represses transcription, but ATR pathway activation leads to ZBTB2 removal from the promoter, cytoplasmic sequestration and activation of viral transcription. Together, our data show that ZASC1/ZBTB2 integrate the functions of TAT and Vpr to maximize HIV-1 gene expression.

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