Search Results (14)

Elite controllers (ECs) represent a unique subset of people living with HIV (PLWHs), who can suppress viral replication without requiring antiretroviral therapy (ART). However, despite this viral control, ECs exhibit increased incidences of various comorbid conditions and heightened systemic inflammation, which has been linked to monocyte activation. In this study, we performed an in-depth phenotypic analysis of monocytes in a cohort of long-term ECs (LTECs) and compared them to non-controller patients with ART-mediated control of HIV replication and to non-controller patients with uncontrolled viral replication. A total of 67 participants were included: 22 LTECs, 15 non-controllers on ART (onART), 10 non-controllers without ART (offART), and 20 uninfected controls (UCs) as a reference group. Monocyte phenotypes were analyzed using spectral flow cytometry with a 13-marker panel. The data were analyzed using two approaches: (a) FCS Express software v.7 to define different subsets of monocytes and assess the levels of expression of eight different monocyte functional markers and (b) R software v.4.1.1 for unsupervised multidimensional analysis, including batch correction, dimensionality reduction, and clustering analysis. Monocyte phenotypic profiling was conducted using three different approaches: (1) assessment of monocyte subsets (classical, intermediate, and non-classical monocytes); (2) evaluation of the levels of expression of eight monocyte functional markers, and (3) characterization of monocyte clusters defined through the dimensionality reduction of flow cytometry data (56 different clusters). The monocyte phenotype of the onART group closely resembled that of the UC group. In contrast, LTECs exhibited important alterations in the monocyte phenotype compared to that of the UCs, including (a) an increased proportion of intermediate monocytes and a decreased proportion of classical monocytes (p < 0.01), (b) altered expressions of functional markers across monocyte subsets (p < 0.05), and (c) alterations in sixteen different monocyte clusters (twelve decreased and four increased, p < 0.05). Many of these alterations were also observed when comparing the LTEC and onART groups. Our findings suggest that monocyte-driven mechanisms may contribute to HIV control in LTECs; however, some of these alterations could also promote systemic inflammation and immune activation. These observations provide a compelling rationale for considering therapeutic interventions in this unique population of PLWHs. Full article

Human Immunodeficiency Virus (HIV) proviral reservoirs are cells that harbor integrated HIV proviral DNA within their nuclear genomes. These cells form a heterogeneous group, represented by peripheral blood mononuclear cells (PBMCs), tissue-resident lymphoid and monocytic cells, and glial cells of the central nervous system. The importance of studying the properties of proviral reservoirs is connected with the inaccessibility of integrated HIV proviral DNA for modern anti-retroviral therapies (ARTs) that block virus reproduction. If treatment is not effective enough or is interrupted, the proviral reservoir can reactivate. Early initiation of ART improves the prognosis of the course of HIV infection, which is explained by the reduction in the proviral reservoir pool observed in the early stages of the disease. Different HIV subtypes present differences in the number of latent reservoirs, as determined by structural and functional differences. Unique signatures of patients with HIV, such as elite controllers, have control over viral replication and can be said to have achieved a functional cure for HIV infection. Uncovering the causes of this phenomenon will bring humanity closer to curing HIV infection, potential approaches to which include stem cell transplantation, clustered regularly interspaced short palindromic repeats (CRISPR)/cas9, “Shock and kill”, “Block and lock”, and the application of broad-spectrum neutralizing antibodies (bNAbs). Full article

(1) Background: The evidence base for the management of spontaneous viral controllers in pregnancy is lacking. We describe the management outcomes of pregnancies in a series of UK women with spontaneous HIV viral control (<100 copies/mL 2 occasions before or after pregnancy off ART). (2) Methods: A multi-centre, retrospective case series (1999–2021) comparing pre- and post-2012 when guidelines departed from zidovudine-monotherapy (ZDVm) as a first-line option. Demographic, virologic, obstetric and neonatal information were anonymised, collated and analysed in SPSS. (3) Results: A total of 49 live births were recorded in 29 women, 35 pre-2012 and 14 post. HIV infection was more commonly diagnosed in first reported pregnancy pre-2012 (15/35) compared to post (2/14), p = 0.10. Pre-2012 pregnancies were predominantly managed with ZDVm (28/35) with pre-labour caesarean section (PLCS) (24/35). Post-2012 4/14 received ZDVm and 10/14 triple ART, p = 0.002. Post-2012 mode of delivery was varied (5 vaginal, 6 PLCS and 3 emergency CS). No intrapartum ZDV infusions were given post-2012 compared to 11/35 deliveries pre-2012. During pregnancy, HIV was detected (> 50 copies/mL) in 14/49 pregnancies (29%) (median 92, range 51–6084). Neonatal ZDV post-exposure prophylaxis was recorded for 45/49 infants. No transmissions were reported. (4) Conclusion: UK practice has been influenced by the change in guidelines, but this has had little impact on CS rates. Full article

Despite remarkable progress, a cure for HIV-1 infection remains elusive. Rebound competent latent and transcriptionally active reservoir cells persevere despite antiretroviral therapy and rekindle infection due to inefficient proviral silencing. We propose a novel “block-lock-stop” approach, entailing long term durable silencing of viral expression towards an irreversible transcriptionally inactive latent provirus to achieve long term antiretroviral free control of the virus. A graded transformation of remnant HIV-1 in PLWH from persistent into silent to permanently defective proviruses is proposed, emulating and accelerating the natural path that human endogenous retroviruses (HERVs) take over millions of years. This hypothesis was based on research into delineating the mechanisms of HIV-1 latency, lessons from latency reversing agents and advances of Tat inhibitors, as well as expertise in the biology of HERVs. Insights from elite controllers and the availability of advanced genome engineering technologies for the direct excision of remnant virus set the stage for a rapid path to an HIV-1 cure. Full article

Like other chronic viral infections, HIV-1 persistence inhibits the development of antigen-specific memory T-cells, resulting in the exhaustion of the immune response and chronic inflammation. Autophagy is a major lysosome-dependent mechanism of intracellular large-target degradation such as lipid and protein aggregates, damaged organelles, and intracellular pathogens. Although it is known that autophagy may target HIV-1 for elimination, knowledge of its function as a metabolic contributor in such viral infection is only in its infancy. Recent data show that elite controllers (EC), who are HIV-1-infected subjects with natural and long-term antigen (Ag)-specific T-cell protection against the virus, are characterized by distinct metabolic autophagy-dependent features in their T-cells compared to other people living with HIV-1 (PLWH). Despite durable viral control with antiretroviral therapy (ART), HIV-1-specific immune dysfunction does not normalize in non-controller PLWH. Therefore, the hypothesis of inducing autophagy to strengthen their Ag-specific T-cell immunity against HIV-1 starts to be an enticing concept. The aim of this review is to critically analyze promises and potential limitations of pharmacological and dietary interventions to activate autophagy in an attempt to rescue Ag-specific T-cell protection among PLWH. Full article

Elite controllers among HIV-1-infected individuals have demonstrated a stronger ability to control the viral load in their bodies. Scientists have isolated antibodies with strong neutralizing ability from these individuals, which can neutralize HIV-1 variations; these are known as broadly neutralizing antibodies. The nucleic acid of some viruses will constantly mutate during replication (such as SARS-CoV-2), which will reduce the protective ability of the corresponding vaccines. The immune escape caused by this mutation is the most severe challenge faced by humans in the battle against the virus. Therefore, developing broad-spectrum vaccines that can induce broadly neutralizing antibodies against various viruses and their mutated strains is the best way to combat virus mutations. Exploring the mechanism by which the human immune system produces broadly neutralizing antibodies and its induction strategies is crucial in the design process of broad-spectrum vaccines. Full article

HIV-exposed seronegative individuals (HESIs) are a small fraction of persons who are multiply exposed to human immunodeficiency virus (HIV), but do not exhibit serological or clinical evidence of HIV infection. In other words, they are groups of people maintaining an uninfected status for a long time, even after being exposed to HIV several times. The long-term non-progressors (LTNPs), on the other hand, are a group of HIV-infected individuals (approx. 5%) who remain clinically and immunologically stable for an extended number of years without combination antiretroviral therapy (cART). Meanwhile, elite controllers are comprise a much lower number (0.5%) of HIV-infected persons who spontaneously and durably control viremia to below levels of detection for at least 12 months, even when using the most sensitive assays, such as polymerase chain reaction (PCR) in the absence of cART. Despite the fact that there is no universal agreement regarding the mechanisms by which these groups of individuals are able to control HIV infection and/or disease progression, there is a general consensus that the mechanisms of protection are multifaceted and include genetic, immunological as well as viral factors. In this review, we analyze and compare the biological factors responsible for the control of HIV in these unique groups of individuals. Full article

In this follow-up study, we investigated the abundance and compartmentalization of blood plasma extracellular miRNA (exmiRNA) into lipid-based carriers—blood plasma extracellular vesicles (EVs) and non-lipid-based carriers—extracellular condensates (ECs) during SIV infection. We also assessed how combination antiretroviral therapy (cART), administered in conjunction with phytocannabinoid delta-9-tetrahydrocannabinol (THC), altered the abundance and compartmentalization of exmiRNAs in the EVs and ECs of SIV-infected rhesus macaques (RMs). Unlike cellular miRNAs, exmiRNAs in blood plasma may serve as minimally invasive disease indicators because they are readily detected in stable forms. The stability of exmiRNAs in cell culture fluids and body fluids (urine, saliva, tears, cerebrospinal fluid (CSF), semen, blood) is based on their association with different carriers (lipoproteins, EVs, and ECs) that protect them from the activities of endogenous RNases. Here, we showed that in the blood plasma of uninfected control RMs, significantly less exmiRNAs were associated with EVs compared to the level (30% higher) associated with ECs, and that SIV infection altered the profile of EVs and ECs miRNAome (Manuscript 1). In people living with HIV (PLWH), host-encoded miRNAs regulate both host and viral gene expression, which may serve as indicators of disease or treatment biomarkers. The profile of miRNAs in blood plasma of PLWH (elite controllers versus viremic patients) are different, indicating that HIV may alter host miRNAome. However, there are no studies assessing the effect of cART or other substances used by PLWH, such as THC, on the abundance of exmiRNA and their association with EVs and ECs. Moreover, longitudinal exmiRNA profiles following SIV infection, treatment with THC, cART, or THC+cART remains unclear. Here, we serially analyzed miRNAs associated with blood plasma derived EVs and ECs. Methods: Paired EVs and ECs were separated from EDTA blood plasma of male Indian rhesus macaques (RMs) in five treatment groups, including VEH/SIV, VEH/SIV/cART, THC/SIV, THC/SIV/cART, or THC alone. Separation of EVs and ECs was achieved with the unparalleled nano-particle purification tool ─PPLC, a state-of-the-art, innovative technology equipped with gradient agarose bead sizes and a fast fraction collector that allows high resolution separation and retrieval of preparative quantities of sub-populations of extracellular structures. Global miRNA profiles of the paired EVs and ECs were determined with RealSeq Biosciences (Santa Cruz, CA) custom sequencing platform by conducting small RNA (sRNA)-seq. The sRNA-seq data were analyzed using various bioinformatic tools. Validation of key exmiRNA was performed using specific TaqMan microRNA stem-loop RT-qPCR assays. Results: We investigated the effect of cART, THC, or both cART and THC together on the abundance and compartmentalization of blood plasma exmiRNA in EVs and ECs in SIV-infected RMs. As shown in Manuscript 1 of this series, were in uninfected RMs, ~30% of exmiRNAs were associated with ECs, we confirmed in this follow up manuscript that exmiRNAs were present in both lipid-based carriers—EVs and non-lipid-based carriers—ECs, with 29.5 to 35.6% and 64.2 to 70.5 % being associated with EVs and ECs, respectively. Remarkably, the different treatments (cART, THC) have distinct effects on the enrichment and compartmentalization pattern of exmiRNAs. In the VEH/SIV/cART group, 12 EV-associated and 15 EC-associated miRNAs were significantly downregulated. EV-associated miR-206, a muscle-specific miRNA that is present in blood, was higher in the VEH/SIV/ART compared to the VEH/SIV group. ExmiR-139-5p that was implicated in endocrine resistance, focal adhesion, lipid and atherosclerosis, apoptosis, and breast cancer by miRNA-target enrichment analysis was significantly lower in VEH/SIV/cART compared to VEH/SIV, irrespective of the compartment. With respect to THC treatment, 5 EV-associated and 21 EC-associated miRNAs were significantly lower in the VEH/THC/SIV. EV-associated miR-99a-5p was higher in VEH/THC/SIV compared to VEH/SIV, while miR-335-5p counts were significantly lower in both EVs and ECs of THC/SIV compared to VEH/SIV. EVs from SIV/cART/THC combined treatment group have significant increases in the count of eight (miR-186-5p, miR-382-5p, miR-139-5p and miR-652, miR-10a-5p, miR-657, miR-140-5p, miR-29c-3p) miRNAs, all of which were lower in VEH/SIV/cART group. Analysis of miRNA-target enrichment showed that this set of eight miRNAs were implicated in endocrine resistance, focal adhesions, lipid and atherosclerosis, apoptosis, and breast cancer as well as cocaine and amphetamine addiction. In ECs and EVs, combined THC and cART treatment significantly increased miR-139-5p counts compared to VEH/SIV group. Significant alterations in these host miRNAs in both EVs and ECs in the untreated and treated (cART, THC, or both) RMs indicate the persistence of host responses to infection or treatments, and this is despite cART suppression of viral load and THC suppression of inflammation. To gain further insight into the pattern of miRNA alterations in EVs and ECs and to assess potential cause-and-effect relationships, we performed longitudinal miRNA profile analysis, measured in terms of months (1 and 5) post-infection (MPI). We uncovered miRNA signatures associated with THC or cART treatment of SIV-infected macaques in both EVs and ECs. While the number of miRNAs was significantly higher in ECs relative to EVs for all groups (VEH/SIV, SIV/cART, THC/SIV, THC/SIV/cART, and THC) longitudinally from 1 MPI to 5 MPI, treatment with cART and THC have longitudinal effects on the abundance and compartmentalization pattern of exmiRNAs in the two carriers. As shown in Manuscript 1 where SIV infection led to longitudinal suppression of EV-associated miRNA-128-3p, administration of cART to SIV-infected RMs did not increase miR-128-3p but resulted in longitudinal increases in six EV-associated miRNAs (miR-484, miR-107, miR-206, miR-184, miR-1260b, miR-6132). Furthermore, administration of cART to THC treated SIV-infected RMs resulted in a longitudinal decrease in three EV-associated miRNAs (miR-342-3p, miR-100-5p, miR181b-5p) and a longitudinal increase in three EC-associated miRNAs (miR-676-3p, miR-574-3p, miR-505-5p). The longitudinally altered miRNAs in SIV-infected RMs may indicate disease progression, while in the cART Group and the THC Group, the longitudinally altered miRNAs may serve as biomarkers of response to treatment. Conclusions: This paired EVs and ECs miRNAome analyses provided a comprehensive cross-sectional and longitudinal summary of the host exmiRNA responses to SIV infection and the impact of THC, cART, or THC and cART together on the miRNAome during SIV infection. Overall, our data point to previously unrecognized alterations in the exmiRNA profile in blood plasma following SIV infection. Our data also indicate that cART and THC treatment independently and in combination may alter both the abundance and the compartmentalization of several exmiRNA related to various disease and biological processes. Full article

A subgroup among people living with HIV (PLHIV) experience viral suppression, sometimes to an undetectable level in the blood and/or are able to maintain a healthy CD4+ T-cell count without the influence of antiretroviral (ARV) therapy. One out of three hundred PLHIV fall into this category, and a large sample of this group can be found in areas with a high prevalence of HIV infection such as Nigeria and South Africa. Understanding the mechanism underpinning the nonprogressive phenotype in this subgroup may provide insights into the control of the global HIV epidemic. This work provides mechanisms of the elite control and nonprogressive phenotype among PLHIV in Nigeria and South Africa and identifies research gaps that will contribute to a better understanding on HIV controllers among PLHIV. Full article

The transactive response DNA-binding protein (TARDBP/TDP-43) influences the processing of diverse transcripts, including that of histone deacetylase 6 (HDAC6). Here, we assessed TDP-43 activity in terms of regulating CD4+ T-cell permissivity to HIV-1 infection. We observed that overexpression of wt-TDP-43 increased both mRNA and protein levels of HDAC6, resulting in impaired HIV-1 infection independently of the viral envelope glycoprotein complex (Env) tropism. Consistently, using an HIV-1 Env-mediated cell-to-cell fusion model, the overexpression of TDP-43 levels negatively affected viral Env fusion capacity. Silencing of endogenous TDP-43 significantly decreased HDAC6 levels and increased the fusogenic and infection activities of the HIV-1 Env. Using pseudovirus bearing primary viral Envs from HIV-1 individuals, overexpression of wt-TDP-43 strongly reduced the infection activity of Envs from viremic non-progressors (VNP) and rapid progressors (RP) patients down to the levels of the inefficient HIV-1 Envs observed in long-term non-progressor elite controllers (LTNP-EC). On the contrary, silencing endogenous TDP-43 significantly favored the infectivity of primary Envs from VNP and RP individuals, and notably increased the infection of those from LTNP-EC. Taken together, our results indicate that TDP-43 shapes cell permissivity to HIV-1 infection, affecting viral Env fusion and infection capacities by altering the HDAC6 levels and associated tubulin-deacetylase anti-HIV-1 activity. Full article

HIV elite controllers (ECs) are characterized by the spontaneous control of viral replication, and by metabolic and autophagic profiles which favor anti-HIV CD4 and CD8 T-cell responses. Extracellular acyl coenzyme A binding protein (ACBP) acts as a feedback inhibitor of autophagy. Herein, we assessed the circulating ACBP levels in ECs, compared to people living with HIV (PLWH) receiving antiretroviral therapy (ART) or not. We found lower ACBP levels in ECs compared to ART-naïve or ART-treated PLWH (p < 0.01 for both comparisons), independently of age and sex. ACBP levels were similar in ECs and HIV-uninfected controls. The expression of the protective HLA alleles HLA-B*27, *57, or *58 did not influence ACBP levels in ECs. ACBP levels were not associated with CD4 or CD8 T-cell counts, CD4 loss over time, inflammatory cytokines, or anti-CMV IgG titers in ECs. In ART-treated PLWH, ACBP levels were correlated with interleukin (IL)-1β levels, but not with other inflammatory cytokines such as IL-6, IL-8, IL-32, or TNF-α. In conclusion, ECs are characterized by low ACBP plasma levels compared to ART-naïve or ART-treated PLWH. As autophagy is key to anti-HIV CD4 and CD8 T-cell responses, the ACBP pathway constitutes an interesting target in HIV cure strategies. Full article

Development of potential HIV-1 curative interventions requires accurate characterization of the proviral reservoir, defined as host-integrated viral DNA genomes that drive rebound of viremia upon halting ART (antiretroviral therapy). Evaluation of such interventions necessitates methods capable of pinpointing the rare, genetically intact, replication-competent proviruses within a background of defective proviruses. This evaluation can be achieved by identifying the distinct integration sites of intact proviruses within host genomes and monitoring the dynamics of these proviruses and host cell lineages over longitudinal sampling. Until recently, molecular genetic approaches at the single proviral level have been generally limited to one of a few metrics, such as proviral genome sequence/intactness, host-proviral integration site, or replication competency. New approaches, taking advantage of MDA (multiple displacement amplification) for WGA (whole genome amplification), have enabled multiparametric proviral characterization at the single-genome level, including proviral genome sequence, host-proviral integration site, and phenotypic characterization of the host cell lineage, such as CD4 memory subset and antigen specificity. In this review, we will examine the workflow of MDA-augmented molecular genetic approaches to study the HIV-1 reservoir, highlighting technical advantages and flexibility. We focus on a collection of recent studies in which investigators have used these approaches to comprehensively characterize intact and defective proviruses from donors on ART, investigate mechanisms of elite control, and define cell lineage identity and antigen specificity of infected CD4+ T cell clones. The highlighted studies exemplify how these approaches and their future iterations will be key in defining the targets and evaluating the impacts of HIV curative interventions. Full article

The normal composition of the intestinal microbiota is a key factor for maintaining healthy homeostasis, and accordingly, dysbiosis is well known to be present in HIV-1 patients. This article investigates the gut microbiota profile of antiretroviral therapy-naive HIV-1 patients and healthy donors living in Latin America in a cohort of 13 HIV positive patients (six elite controllers, EC, and seven non-controllers, NC) and nine healthy donors (HD). Microbiota compositions in stool samples were determined by sequencing the V3-V4 region of the bacterial 16S rRNA, and functional prediction was inferred using PICRUSt. Several taxa were enriched in EC compared to NC or HD groups, including Acidaminococcus, Clostridium methylpentosum, Barnesiella, Eubacterium coprostanoligenes, and Lachnospiraceae UCG-004. In addition, our data indicate that the route of infection is an important factor associated with changes in gut microbiome composition, and we extend these results by identifying several metabolic pathways associated with each route of infection. Importantly, we observed several bacterial taxa that might be associated with different viral subtypes, such as Succinivibrio, which were more abundant in patients infected by HIV subtype B, and Streptococcus enrichment in patients infected by subtype C. In conclusion, our data brings a significant contribution to the understanding of dysbiosis-associated changes in HIV infection and describes, for the first time, differences in microbiota composition according to HIV subtypes. These results warrant further confirmation in a larger cohort of patients. Full article

Quantifying HIV Envelope (Env)-specific antibodies in HIV⁺ plasma is useful for interpreting antibody dependent cellular cytotoxicity assay results. HIV Env, the only viral protein expressed on the surface of infected cells, has a native trimeric closed conformation on cells infected with wild-type HIV. However, CD4⁺ uninfected bystander cells in HIV⁺ cell cultures bind gp120 shed from HIV⁺ cells exposing CD4-induced epitopes normally hidden in native Env. We used flow-cytometry based assays to quantify antibodies in HIV⁺ plasma specific for native trimeric Env or gp120/CD4 conjugates using CEM.NKr.CCR5 (CEM) cells infected with HIV (iCEM) or coated with recombinant gp120 (cCEM), as a surrogate for gp120⁺ HIV^- bystander cells. Results from both assays were compared to those of a plate-based ELISA to monomeric gp120. The levels of Env-specific antibodies to cCEM and iCEM, measured by flow cytometry, and to gp120 by ELISA were positively correlated. More antibodies in HIV⁺ plasma recognized the gp120 conformation exposed on cCEM than on iCEM. Comparisons of plasma from untreated progressors, treated progressors, and elite controllers revealed that antibodies to Env epitopes were the lowest in treated progressors. Plasma from elite controllers and untreated progressors had similarly high levels of Env-specific antibodies, despite elite controllers having undetectable HIV viral loads, while untreated progressors maintained high viral loads. Full article