Shocking HIV-1 with immunomodulatory latency reversing agents.

The "shock-and-kill" strategy is one of the most explored HIV-1 cure approaches to eliminate latent virus. This strategy is based on HIV-1 reactivation using latency reversing agents (LRAs) to reactivate latent proviruses (the "shock" phase) and to induce subsequent elimination of the reactivated cells by immune responses or virus-induced cytopathic effects (the "kill" phase). Studies using immunomodulatory LRAs such as blockers of immune checkpoint molecules, toll-like receptor agonists, cytokines and CD8+ T cell depleting antibodies showed promising potential as LRAs inducing directly or indirectly cellular pathways known to control HIV transcription. However, the precise molecular mechanisms by which these immunomodulatory LRAs reverse latency remain incompletely understood. Together with the heterogenous nature of HIV-1 latency, this lack of understanding complicates efforts to develop more efficient and safer cure strategies. Hence, deciphering those mechanisms is pivotal in designing approaches to eliminate latent HIV infection.

Efficacy, durability, and tolerability of dolutegravir/lamivudine and dolutegravir/rilpivirine for the treatment of HIV in a real-world setting in Belgium.

OBJECTIVES: A paradigm shift from three-drug regimens to two-drug regimens (2DRs) is currently taking place in real-world clinical practice. This study aimed to describe the efficacy, durability, and tolerability of dolutegravir (DTG)/lamivudine (3TC) and DTG/rilpivirine (RPV) in a real-world setting. METHODS: This was a retrospective, observational, multicentre (ten centres in Belgium) study involving adult treatment-naïve and treatment-experienced people living with HIV on DTG/3TC or DTG/RPV between 1 January 2019 and 30 September 2020. The primary endpoint was rate of virological suppression (VS; plasma HIV-1 viral load [VL] <50 copies/ml) using an on-treatment analysis. Main secondary endpoints included the proportion of people that experienced loss of VS (LVS; defined as two consecutive HIV-1 VLs of >200 copies/ml after initially achieving VS) and a resistance analysis at the time of LVS; rate, incidence, and reasons for discontinuation of treatment (stopping treatment or changing any component of the 2DR); and change in weight, along with the proportion of people reporting a >10% weight gain. Ordinal logistic regression analysis examined associations between baseline variables and >10% on-treatment weight gain. RESULTS: Overall, 948 people were included, of whom 734 (77%) were on DTG/3TC and 214 (23%) were on DTG/RPV. Baseline characteristics included 54% aged ≥50 years, 31% female, 31% Black sub-Saharan African, 95% treatment-experienced, and 8% with HIV-1 VL ≥50 copies/ml. Through 48 weeks, the rate of VS for the overall cohort was 98.3% (99.1% with 3TC; 96.2% with RPV). LVS was observed in 0.5% (n = 5) of the overall population (n = 1 [3TC group], n = 4 [RPV group]). There were 40 treatment discontinuations (4.2%, n = 27 [3TC group]; n = 13 [RPV group]), corresponding to an incidence of 4.7 per 100 patient-years. The most common reason for discontinuation was an adverse event (1.4%), with neurotoxicity the most frequent (0.5%). Median on-treatment weight gain at week 48 was 1 kg (interquartile range [IQR] -1-3) overall, 1 kg (IQR -1-3) in the 3TC group, and 2 kg (IQR 0-4) in the RPV group. A >10% weight increase was observed in 6.3% of people. Regression analysis showed that being on a tenofovir disoproxil fumarate-based regimen prior to 2DR initiation was the only variable associated with a >10% increase in weight from baseline (odds ratio 3.48; 95% confidence interval 1.13-10.68; p = 0.038). CONCLUSION: In this real-world analysis, the 2DRs analysed were effective, durable, and safe for those who were treatment-naive and treatment-experienced. A slight increase in weight was associated with these regimens.

Efficacy, durability, and tolerability of bictegravir/emtricitabine/tenofovir alafenamide for the treatment of HIV in a real-world setting in Belgium.

OBJECTIVES: Our objective was to evaluate the efficacy, durability, and tolerability of bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) in a real-world setting in Belgium. METHODS: This was a retrospective, multicentre cohort study involving adult treatment-naïve (TN) and treatment-experienced (TE) people living with HIV receiving BIC/FTC/TAF between 1 January 2019 and 30 September 2020. The primary outcome was rate of virological suppression (plasma HIV-1 viral load <50 copies/mL; on-treatment analysis) at weeks 24 and 48. The main secondary outcomes included loss of virological suppression (LVS; two consecutive viral loads of >200 copies/mL after being virologically suppressed) by week 48 and analysis of resistance-associated mutations at time of LVS; tolerability of BIC/FTC/TAF over the 48-week study period; and change in weight and proportion of participants reporting a >10% weight gain at week 48. RESULTS: Overall, 2001 participants were included. Through 48 weeks, overall rate of virological suppression was 93.5%, with similar results observed in the following subgroups: age ≥50 years (92.7%), women (92.8%), Black sub-Saharan African (91%), TN (94%), TE (93.2%), and non-suppressed at baseline (86.6%). LVS was observed in 0.7% (n = 14) of participants, with one participant developing resistance-associated mutations to nucleoside reverse transcriptase inhibitors (184 V) and integrase strand transfer inhibitors (263KR). Of the 131 (6.5%) treatment discontinuations, the most common reason was an adverse event (2.4%), with the most frequent being central nervous system/psychiatric (0.4%) and gastrointestinal (0.4%) toxicity. Median weight gain at week 48 was 2 kg (interquartile range -1 to 5), and a >10% weight increase was observed in 11.6% of participants. CONCLUSION: In this large real-world cohort, BIC/FTC/TAF showed excellent virological efficacy in a diverse population of patients with HIV. Rare occurrence of emergent drug resistance was observed, and treatment was well tolerated.

Genetic Architecture of Ischaemic Strokes after COVID-19 Shows Similarities with Large Vessel Strokes.

We aimed to analyse whether patients with ischaemic stroke (IS) occurring within eight days after the onset of COVID-19 (IS-COV) are associated with a specific aetiology of IS. We used SUPERGNOVA to identify genome regions that correlate between the IS-COV cohort (73 IS-COV cases vs. 701 population controls) and different aetiological subtypes. Polygenic risk scores (PRSs) for each subtype were generated and tested in the IS-COV cohort using PRSice-2 and PLINK to find genetic associations. Both analyses used the IS-COV cohort and GWAS from MEGASTROKE (67,162 stroke patients vs. 454,450 population controls), GIGASTROKE (110,182 vs. 1,503,898), and the NINDS Stroke Genetics Network (16,851 vs. 32,473). Three genomic regions were associated (p-value < 0.05) with large artery atherosclerosis (LAA) and cardioembolic stroke (CES). We found four loci targeting the genes PITX2 (rs10033464, IS-COV beta = 0.04, p-value = 2.3 × 10-2, se = 0.02), previously associated with CES, HS6ST1 (rs4662630, IS-COV beta = -0.04, p-value = 1.3 × 10-3, se = 0.01), TMEM132E (rs12941838 IS-COV beta = 0.05, p-value = 3.6 × 10-4, se = 0.01), and RFFL (rs797989 IS-COV beta = 0.03, p-value = 1.0 × 10-2, se = 0.01). A statistically significant PRS was observed for LAA. Our results suggest that IS-COV cases are genetically similar to LAA and CES subtypes. Larger cohorts are needed to assess if the genetic factors in IS-COV cases are shared with the general population or specific to viral infection.

[An emerging cause of chronic fatigue and pain : post-COVID-19 condition or long COVID]. / Une cause émergente de fatigue et de douleurs chroniques : l'affection post-COVID-19 ou COVID long.

Some individuals who have been infected with SARS-CoV-2 can experience long-term effects from their infection, known as post-COVID conditions, post-acute sequelae of COVID-19 or long COVID. Different underlying mechanisms can lead to long COVID, none of which are mutually exclusive. Lingering symptoms can persist years after SARS-CoV-2 infection, including fatigue, muscle weakness, tachycardia, dyspnea and various neurological symptoms. The symptomatology is partly similar to that reported by people with chronic fatigue syndrome and other unwell studied long-lasting diseases that may occur after other infections. People who have experienced more severe COVID-19 illness are at higher risk of developing long COVID, although anyone who was infected can experience post-COVID conditions. Importantly, unvaccinated individuals are more likely to develop long COVID. Here we review the current knowledge and discuss key findings regarding the epidemiology and physiopathology of long COVID. We briefly review current diagnostic and treatment options that remain so far largely insufficient.

Certains individus infectés par le SARS-CoV-2 peuvent présenter des symptômes à long terme, évoluant parfois durant plusieurs années. Il est alors question d'affection post-COVID-19 ou COVID long. Les symptômes sont très polymorphes, fluctuants, et comprennent, notamment, une fatigue intense, des douleurs articulaires et musculaires, de la dyspnée, de la tachycardie, ainsi qu'une constellation de plaintes neurologiques. Cette symptomatologie est, en partie, similaire à celle du syndrome de fatigue chronique et est retrouvée également après d'autres types d'infections. Les mécanismes à l'origine du COVID long sont probablement multiples et encore mal connus. Si le COVID long peut toucher tout individu infecté par le SARS-CoV-2, certains groupes sont plus à risque, notamment les personnes non vaccinées ou les individus ayant présenté une infection sévère. Dans cet article, nous résumons les connaissances actuelles et mettons en lumière les découvertes clés quant à l'épidémiologie et aux mécanismes physiopathologiques du COVID long. Nous discutons aussi des critères diagnostiques et des options thérapeutiques qui sont, à ce jour, largement insuffisantes.

Impact of COVID-19 on the Belgian HIV epidemic: slowdown of HIV transmission and testing and adaptation of care.

BACKGROUND: To gain insight into the impact of the COVID-19 pandemic and containment measures on the HIV epidemic and services, this study aims to describe HIV trends in 2020 and compare them with previous years. METHODS: Belgian national HIV surveillance data 2017-2020 were analysed for trends in HIV testing, HIV diagnoses, VL measurements, ART uptake and PrEP purchase. Descriptive statistics from 2020 are compared to annual averages from 2017 to 2019 (proportional difference, %). RESULTS: In 2020, 725 HIV infections were diagnosed in Belgium (- 21.5% compared to 2019). The decline was most pronounced during the first lockdown in April-May but also present in July-December. The number of HIV tests performed decreased by 17.6% in 2020, particularly in March-May and October-December (- 57.5% in April and -25.4% in November 2020 compared to monthly 2017-19 numbers). Diagnosis of acute HIV infections decreased by 47.1% in 2020 (n = 27) compared to 2019 (n = 51). Late HIV diagnoses decreased by 24.7% (95% CI [- 40.7%; -9.7%]) in 2020 compared to 2019. Of patients in care in 2019, 11.8% interrupted HIV care in 2020 compared to 9.1% yearly in the 3 previous years. The number of HIV patients with VL monitoring per month dropped in March-May 2020, whilst proportions of VL suppression and ART coverage remained above 86% and 98.5% respectively in 2020. PrEP purchases, number of purchasers and starters dropped during April-May 2020 (respectively - 45.7%, - 47.4%, - 77.9% in April compared to February 2020). CONCLUSIONS: The significant decrease in HIV diagnoses in Belgium in 2020 coincided with the COVID-19 pandemic and following containment measures, particularly in April-May during the first lockdown. A slowdown of HIV transmission due to reduced HIV risk exposure is suggested by the halving in diagnosis of acute HIV infections in March-December 2020 compared to the previous year, and the adaptive decrease in PrEP use and PrEP initiation from April onwards. Despite a slight increase in HIV care interruptions, the indicators of quality of HIV care remained stable. Access to prevention, testing and care for all people living with HIV and at risk of acquiring HIV is a priority during and after times of pandemic.

Impact of switch from tenofovir disoproxil fumarate-based regimens to tenofovir alafenamide-based regimens on lipid profile, weight gain and cardiovascular risk score in people living with HIV.

BACKGROUND: As cardiovascular diseases represent the main cause of non-AIDS related death in people living with HIV (PLWH) with undetectable viral load, we evaluated lipid profile, weight gain and calculated cardiovascular risk change after switching from tenofovir disoproxil fumarate (TDF)-based regimens to tenofovir alafenamide (TAF)-based regimens. METHODS: For this retrospective study, we selected HIV-infected patients with suppressed viral load who fitted in one of the two groups below: First group (TDF/TDF): Patients treated continuously with TDF-based regimens. Second group (TDF/TAF): Patients treated with TDF-regimens during at least 6 months then switched to TAF-regimens while maintaining other drugs unchanged. Available data included date of birth, gender, ethnicity, lymphocyte T CD4+ count, weight, height, blood pressure, current/ex/non-smoker, diabetes mellitus, familial cardiovascular event, lipid profile, duration and nature of antiretroviral therapy. Lipid parameters, weight and calculated cardiovascular risk using 5-year reduced DAD score algorithm [Friis-Møller et al. in Eur J Cardiovasc Prev Rehabil 17:491-501, 2010] were analyzed in each groups. RESULTS: Switching from TDF to TAF resulted in a significant increase in triglycerides levels, total cholesterol and HDL cholesterol. LDL cholesterol and total cholesterol/HDL ratio did not show significant changes. Calculated cardiovascular risk increased after switch from TDF- to TAF-based therapy. CONCLUSIONS: Together with favorable outcomes at the bone and kidney levels, potential negative impact of TAF on lipid profile should be included in the reflection to propose the most appropriate and tailored ARV treatment.

Decrease in late presentation for HIV care in Kinshasa, DRC, 2006-2020.

INTRODUCTION: Late presentation for HIV care is a well-described issue for the success of ART outcomes and the cause of higher morbidity, mortality and further transmission. Monitoring the level of late presentation and understanding the factors associated with it would help to tailor screening and information strategies for better efficiency. We performed a retrospective cohort study in Kinshasa, the capital of the DRC. The studied population included HIV-positive adults newly enrolled in HIV care between January 2006 and June 2020 at 25 HIV urban care facilities. Patient information collected at presentation for HIV care included age, sex, WHO clinical stage and screening context. We used 2 definitions of late presentation: the WHO definition of advanced HIV disease (WHO stage 3/4 or CD4 cell count < 200 cells/mm3) and a more inclusive definition (WHO stage 3/4 or CD4 cell count < 350 cells/mm3). RESULTS: A total of 10,137 HIV-infected individuals were included in the analysis. The median age was 40 years; 68% were female. A total of 45.9% or 47.5% of the patients were late presenters, depending on the definition used. The percentage of patients with late presentation (defined as WHO stage 3/4 or CD4 cell count < 350 cells/mm3) decreased during recent years, from 70.7% in 2013 to 46.5% in 2017 and 23.4% in 2020. Age was associated with a significantly higher risk of LP (p < 0.0001). We did not observe any impact of sex. CONCLUSIONS: The frequency of late presentation for care is decreasing in Kinshasa, DRC. Efforts have to be continued. In particular, the issue of late diagnosis in older individuals should be addressed.

Detectability of HIV Residual Viremia despite Therapy Is Highly Associated with Treatment with a Protease Inhibitor-Based Combination Antiretroviral Therapy.

HIV persistence despite therapy contributes to chronic immune activation and inflammation, increasing the risk of aging-associated events in HIV-infected individuals. We sought here to better understand the complex link between clinical and treatment features and HIV persistence despite therapy. A total of 11,045 samples from 1,160 individuals under combination antiretroviral therapy (cART) with an unquantifiable viral load (VL; limit of quantification, 20 copies/ml) were categorized as detectable or undetectable depending on the detection of a PCR signal using a commercially available assay. Generalized estimating equation (GEE) regression was used to model viral load detectability and to assess the determinants of residual viremia (RV; VL detected below 20 copies/ml) despite therapy. A high VL zenith was associated with a higher probability to have a detectable viremia under cART. Conversely, the probability to have a detectable viral load below 20 copies/ml decreased with time under therapy. Of therapy regimens, protease inhibitor (PI)-based cART was associated with a significantly higher probability of detectable RV compared to nonnucleoside transcriptase inhibitor- or integrase inhibitor-based cART. We found that a PI-based treatment regimen is highly associated with an increased frequency of RV, supporting previous evidence suggesting that PI-based cART regimens could favor ongoing viral replication in some individuals.

HIV Latency: Should We Shock or Lock?

Combinatory antiretroviral therapy (cART) increases the survival and quality of life of HIV-1-infected patients. However, interruption of therapy almost invariably leads to the re-emergence of detectable viral replication because HIV-1 persists in viral latent reservoirs. Improved understanding of the molecular mechanisms involved in HIV-1 latency has paved the way for innovative strategies that attempt to purge latent virus. In this article we discuss the results of the broadly explored 'shock and kill' strategy, and also highlight the major hurdles facing this approach. Finally, we present recent innovative works suggesting that locking out latent proviruses could be a potential alternative therapeutic strategy.

Impact of coronavirus pandemic and containment measures on HIV diagnosis.

During the last months and following the implementation of containment measures in the context of coronavirus disease 2019 (COVID-19) pandemic, the number of new human immunodeficiency virus (HIV) diagnoses radically decreased in Liege AIDS Reference Center, Belgium. The number of HIV screening tests has also dramatically dropped down to an unprecedented level. This decline of HIV diagnosis is caused by missed diagnoses of individuals infected before the establishment of such measures and to the reduction of high-risk sexual behaviours during the COVID-19 pandemic.

Molecular Control of HIV and SIV Latency.

The HIV latent reservoirs are considered as the main hurdle to viral eradication. Numerous mechanisms lead to the establishment of HIV latency and act at the transcriptional and post-transcriptional levels. A better understanding of latency is needed in order to ultimately achieve a cure for HIV. The mechanisms underlying latency vary between patients, tissues, anatomical compartments, and cell types. From this point of view, simian immunodeficiency virus (SIV) infection and the use of nonhuman primate (NHP) models that recapitulate many aspects of HIV-associated latency establishment and disease progression are essential tools since they allow extensive tissue sampling as well as a control of infection parameters (virus type, dose, route, and time).

The Molecular Biology of HIV Latency.

HIV remains incurable due to the existence of a reservoir of cells that harbor intact integrated genomes of the virus in the absence of viral replication. This population of infected cells remains invisible to the immune system and is not targeted by the drugs used in the current antiretroviral therapies (cART). Reversal of latency by the use of inhibitors of chromatin-remodeling enzymes has been studied extensively in an attempt to purge this reservoir of latent HIV but has thus far not shown any success in clinical trials. The full complexity of latent HIV infection has still not been appreciated, and the gaps in knowledge prevent development of adequate small-molecule compounds that can effectively perturb this reservoir. In this review, we will examine the role of epigenetic silencing of HIV transcription, posttranscriptional regulation, and mRNA processing in promoting HIV-1 latency.

An In-Depth Comparison of Latency-Reversing Agent Combinations in Various In Vitro and Ex Vivo HIV-1 Latency Models Identified Bryostatin-1+JQ1 and Ingenol-B+JQ1 to Potently Reactivate Viral Gene Expression.

The persistence of latently infected cells in patients under combinatory antiretroviral therapy (cART) is a major hurdle to HIV-1 eradication. Strategies to purge these reservoirs are needed and activation of viral gene expression in latently infected cells is one promising strategy. Bromodomain and Extraterminal (BET) bromodomain inhibitors (BETi) are compounds able to reactivate latent proviruses in a positive transcription elongation factor b (P-TEFb)-dependent manner. In this study, we tested the reactivation potential of protein kinase C (PKC) agonists (prostratin, bryostatin-1 and ingenol-B), which are known to activate NF-κB signaling pathway as well as P-TEFb, used alone or in combination with P-TEFb-releasing agents (HMBA and BETi (JQ1, I-BET, I-BET151)). Using in vitro HIV-1 post-integration latency model cell lines of T-lymphoid and myeloid lineages, we demonstrated that PKC agonists and P-TEFb-releasing agents alone acted as potent latency-reversing agents (LRAs) and that their combinations led to synergistic activation of HIV-1 expression at the viral mRNA and protein levels. Mechanistically, combined treatments led to higher activations of P-TEFb and NF-κB than the corresponding individual drug treatments. Importantly, we observed in ex vivo cultures of CD8+-depleted PBMCs from 35 cART-treated HIV-1+ aviremic patients that the percentage of reactivated cultures following combinatory bryostatin-1+JQ1 treatment was identical to the percentage observed with anti-CD3+anti-CD28 antibodies positive control stimulation. Remarkably, in ex vivo cultures of resting CD4+ T cells isolated from 15 HIV-1+ cART-treated aviremic patients, the combinations bryostatin-1+JQ1 and ingenol-B+JQ1 released infectious viruses to levels similar to that obtained with the positive control stimulation. The potent effects of these two combination treatments were already detected 24 hours post-stimulation. These results constitute the first demonstration of LRA combinations exhibiting such a potent effect and represent a proof-of-concept for the co-administration of two different types of LRAs as a potential strategy to reduce the size of the latent HIV-1 reservoirs.

Recurrence of visceral and muco-cutaneous leishmaniasis in a patient under immunosuppressive therapy.

BACKGROUND: Leishmaniasis is a protozoan disease caused by parasites of the genus Leishmania, transmitted to humans by sandflies. The diagnosis of leishmaniasis is often challenging as it mimics many other infectious or malignant diseases. The disease can present in three ways: cutaneous, mucocutaneous, or visceral leishmaniasis, which rarely occur together or consecutively. CASE PRESENTATION: The patient was a 52 years old immunosuppressed Belgian woman with a long history of severe rheumatoid arthritis. She underwent bone marrow biopsy to explore thrombocytopenia. Diagnosis of visceral leishmaniasis was made by identification of Leishman Donovan (LD) bodies in macrophages. Treatment with liposomal amphotericin B was successful. She later developed cutaneous leishmaniasis treated with amphotericin B lipid complex. She next presented with relapsing cutaneous lesions followed by rapidly progressing lymphadenopathies. Biopsy confirmed the diagnosis of leishmaniasis. Treatments by miltefosine, amphotericin B, N-methyl-glucamine antimoniate were subsequently initiated. She later presented a recurrent bone marrow involvement treated with intramuscular paromomycin and miltefosine. She died two years later from leukemia. At the time of death, she presented with a mucosal destruction of the nose. A Leishmania-specific PCR (Polymerase Chain Reaction) identified L. infantum as etiological agent. CONCLUSIONS: Clinicians should be aware of the potential concomitant or sequential involvement of multiple anatomic localizations of Leishmania in immunosuppressed patients.

[Update in HIV therapy: tenofovir alafenamide]. / Actualité thérapeutique dans le VIH : le ténofovir alafénamide.

Since the first treatments against human immunodeficiency virus (HIV) have appeared in 1987, important progress has been accomplished. Twenty-four molecules are currently available but only some of them are in common use on account of their easy administration or their weak adverse effects. Tenofovir disoproxil fumarate (TDF) is a commonly used nucleoside reverse-transcriptase inhibitor (NRTI) of HIV. However, taking TDF is sometimes associated with renal toxicity and increased bone demineralization. Tenofovir alafenamide (TAF) is a new prodrug of tenofovir (TFV) whose security profile is more interesting as far as renal and bone complications are concerned, due to a much lower serum concentration and a high intracellular concentration.

Depuis l'apparition des premiers traitements contre le virus de l'immunodéficience humaine (VIH) en 1987, d'importantes avancées ont été réalisées. Vingt-quatre molécules sont actuellement disponibles, mais seules certaines d'entre elles sont fréquemment utilisées en raison de leur facilité d'administration et de leurs faibles effets secondaires. Le ténofovir disoproxil fumarate (TDF) est un inhibiteur nucléotidique de la transcriptase inverse (INTI) du VIH couramment utilisé. Cependant, la prise de TDF est parfois associée à une toxicité rénale ainsi qu'à une déminéralisation osseuse accrue. Le ténofovir alafénamide (TAF) est un nouveau promédicament du ténofovir (TFV) au profil de sécurité plus intéressant sur les plans rénal et osseux, en vertu d'une concentration sérique nettement inférieure et d'une haute concentration intracellulaire.

Dengue and chikungunya: future threats for Northern Europe?

Arthropod-borne viral diseases are likely to be affected by the consequences of climate change with an increase in their distribution and intensity. Among these infectious diseases, chikungunya and dengue viruses are two (re)emergent arboviruses transmitted by Aedes species mosquitoes and which have recently demonstrated their capacity for rapid expansion. They most often cause mild diseases, but they can both be associated with complications and severe forms. In Europe, following the establishment of invasive Aedes spp, the first outbreaks of autochtonous dengue and chikungunya have already occurred. Northern Europe is currently relatively spared, but climatic projections show that the conditions are permissive for the establishment of Aedes albopictus (also known as the tiger mosquito) in the coming decades. It is therefore essential to question and improve the means of surveillance in northern Europe, at the dawn of inevitable future epidemics.

Persistent HIV-1 transcription during ART: time to reassess its significance?

PURPOSE OF REVIEW: Despite suppressive antiretroviral therapy (ART), HIV-1 reservoirs persist and reignite viral replication if therapy is interrupted. Persistence of the viral reservoir in people with HIV-1 (PWH) is the main obstacle to an HIV-1 cure. The reservoirs are not transcriptionally silent, and viral transcripts can be detected in most ART-treated individuals. Here, we review the recent progress in the characterization of persistent HIV-1 transcription during ART. RECENT FINDINGS: Evidence from several studies indicates that, although cell-associated unspliced (US) HIV-1 RNA is abundantly expressed in ART-treated PWH, intact full-length US transcripts are rare and most US RNA is derived from defective proviruses. The transcription- and translation-competent defective proviruses, previously considered irrelevant, are increasingly being linked to residual HIV-1 pathogenesis under suppressive ART. Recent data suggest a continuous crosstalk between the residual HIV-1 activity under ART and the immune system. Persistent HIV-1 transcription on ART, despite being mostly derived from defective proviruses, predicts viral rebound upon therapy interruption, suggesting its role as an indicator of the strength of the host antiviral immune response that is shaping the viral rebound. SUMMARY: In light of the recent findings, the significance of persistent HIV-1 transcription during ART for the long-term health of PWH and the cure research should be reassessed.