Project description:CCR5 is the main HIV co-receptor. We aimed to (1) compare CCR5 expression on immune cells between people living with HIV (PLHIV) using combination antiretroviral therapy (cART) and HIV-uninfected controls, (2) relate CCR5 expression to viral reservoir size and (3) assess detereminants of CCR5 expression. Percentages of CCR5 positive cells (%) and CCR5 mean fluorescence intensity (MFI) assessed by flow cytometry in monocytes and lymphocyte subsets were correlated to host factors, HIV-1 cell-associated (CA)-RNA and CA-DNA, plasma inflammation markers and metabolites.
Project description:The study examined proviral and neighboring gene transcription at sites of intact latent HIV-1 integration in cultured T cells obtained directly from people living with HIV, as well as engineered primary T cells and cell lines and showed that the site of integration has a dominant effect on the transcriptional activity of intact HIV-1 proviruses in the latent reservoir
Project description:Understanding the complexity of the long-lived HIV reservoir during antiretroviral therapy (ART) remains a major impediment for HIV cure research. To address this, we developed single-cell viral ASAPseq to precisely define the unperturbed peripheral blood HIV-infected memory CD4+ T cell reservoir from antiretroviral treated people living with HIV (ART-PLWH) via the presence of integrated accessible proviral DNA in concert with epigenetic and cell surface protein profiling. We identified profound reservoir heterogeneity within and between ART-PLWH, characterized by novel and known surface markers within total and individual memory CD4+ T cell subsets. We further uncovered novel epigenetic profiles and transcription factor motifs enriched in HIV-infected cells that suggest infected cells with accessible provirus, irrespective of reservoir distribution, are poised for reactivation during ART treatment. Together, our findings reveal the extensive inter- and intrapersonal cellular heterogeneity of the HIV reservoir, and establish an initial multiomic atlas to develop targeted reservoir elimination strategies.
Project description:The latent reservoir of HIV persists for decades in people living with HIV (PWH) on antiretroviral therapy (ART). To determine if persistence arises from the natural dynamics of memory CD4+ T cells harboring HIV, we compared the clonal dynamics of HIV proviruses to that of memory CD4+ T cell receptors (TCRβ) from the same PWH and from HIV-seronegative people. We show that clonal dominance of HIV proviruses and antigen-specific CD4+ T cells are similar but that the field’s understanding of the persistence of the less clonally dominant reservoir is significantly limited by undersampling. We demonstrate that increasing reservoir clonality over time and differential decay of intact and defective proviruses cannot be explained by mCD4+ T cell kinetics alone. Finally, we develop a stochastic model of TCRβ and proviruses that recapitulates experimental observations and suggests that HIV-specific negative selection mediates approximately 6% of intact and 2% of defective proviral clearance. Thus, HIV persistence is mostly, but not entirely, driven by natural mCD4+ T cell kinetics.
Project description:The study examined proviral and neighboring gene transcription at sites of intact latent HIV-1 integration in cultured T cells obtained directly from people living with HIV, as well as engineered primary T cells and cell lines and showed that the site of integration has a dominant effect on the transcriptional activity of intact HIV-1 proviruses in the latent reservoir
Project description:Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), is the most common coinfection among people living with HIV-1. This coinfection alters the efficacy of the immune response against both HIV-1 and Mtb, and is associated with accelerated HIV-1 disease progression and reduced survival. Enhanced HIV-1 replication in macrophages induced by Mtb coinfection may contribute to the worsened clinical outcomes observed in HIV-1/TB coinfected individuals. However, the impact of the HIV-1/TB coinfection on HIV-1 replication and latency in CD4+ T cells remains poorly studied. In this study, we used the acellular fraction of tuberculous pleural effusion (TB-PE) as a proxy for the microenvironment generated by Mtb infection. Using this physiologically relevant fluid, we investigated whether viral replication and HIV-1 latency in CD4+ T cells are affected by a TB-associated microenvironment. Interestingly, our results revealed that TB-PE shaped the transcriptional profile of CD4+ T cells impairing T cell receptor-dependent cell activation and decreased HIV-1 replication. Moreover, this immunosuppressive TB microenvironment promoted viral latency and inhibited HIV-1 reactivation in CD4+ T cells from people living with HIV-1. This study indicates that the immune response induced by TB may contribute to the persistence of the viral reservoir by silencing HIV-1 expression in individuals coinfected with both pathogens, allowing the virus to persist undetected by the immune system and increasing the size of the HIV-1 latent reservoir in cells at the site of the coinfection.
Project description:Despite antiretroviral therapy, HIV mainly persists in memory CD4+ T cells in people living with HIV. Most long-lived viral reservoir cells are infected near the time of therapy initiation. A better understanding of the early events in reservoir seeding presents opportunities for preventing latent reservoir formation. Here, we demonstrated that CD4+ T cells expressing CCR5, permissive to HIV-1 infection, are effector or terminally differentiated cells. BACH2 is expressed by a small subset of CCR5+ cells and reverses their terminal differentiation. BACH2-mediated memory differentiation is impeded due to heightened inflammation before treatment initiation. Mice with a BACH2 knockout human immune system has a reduced frequency of HIV-1 reservoir cells and do not experience virus rebound after treatment discontinuation. Our study reveals that BACH2 is essential to the seeding of long-lived HIV-1 reservoir and demonstrates the potential of targeting BACH2 at the time of treatment initiation to eliminate HIV-1 reservoirs in T cells.
2024-11-01 | GSE275936 | GEO
Project description:Gut microbiome in viral-suppressed people living with HIV
Project description:We performed a comprehensive characterization of Vδ1 T cells in blood of people with HIV-1 on antiretroviral therapy and HIV-seronegative controls, in a substudy of the ANRS EP61 GALT study (NCT02906137). We deciphered the single-cell transcriptome of Vδ1 cells. Vδ1 T cells were mainly terminally differentiated effectors that expanded in the blood with some trafficking with the gut of people with HIV-1. Most expressed CX3CR1 and displayed a highly cytotoxic profile, but low cytokine production, supported by a transcriptomic shift towards enhanced effector lymphocytes. The increase in Vδ1 T cells observed in people with HIV-1 has multiple triggers, particularly CMV and microbiota, and may in turn contribute to the control of the HIV-1 reservoir.
Project description:Immune activation in people living with HIV on anti-retroviral therapy is associated with increased risk of morbidity and mortality, but the underlying mechanisms are poorly understood. To identify whether perturbation of immunological pathways persist at systems level, we compared genome-wide whole blood transcriptomes from 26 people living with HIV on long-term anti-retroviral therapy with 12 HIV-negative healthy controls. All participants were Caucasian male adults recruited from London, UK. People living with HIV were on anti-retroviral therapy for a median of 8.5 years (interquartile range 3-16 years). They had undetectable plasma HIV viral load (<40 copies/ml) and median circulating CD4 counts of 703 cells/µl (interquartile range 491-841 cells/µl).