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Vandekerckhove, L.

Publications and source records attributed to Vandekerckhove, L..

10 recordsLinked to original sources

An eicosanoid-enriched follicular microenvironment shapes germinal centre immune dynamics in antiretroviral-treated PLWH

Delineating the follicular (F) cellular and molecular landscape in HIV infection is essential for understanding neutralizing antibody responses and HIV reservoir maintenance. Multiplex imaging analysis revealed a less differentiated profile for follicular helper CD4 T cells (TFH) and significantly increased follicular CD25lo/hiFoxp3hi T cells in lymph nodes (LNs) from antiretroviral treated (cART) compared to viremic (Vir) people living with HIV (PLWH). Spatial transcriptomics identified distinct inflammatory follicular microenvironments in Vir and cART LNs, characterized by interferon and eicosanoid enrichment, respectively. In an independent cohort, scRNA-sequencing analysis of LN-derived cells revealed an enrichment of eicosanoid-related pathways in follicular immune cell types in non-neutralizers compared to neutralizers PLWH. In vitro infection and in situ multimodal investigation of HIV DNA+ cell microenvironments suggested a potential role of PGE2/Eicosanoids in maintaining viral reservoirs in cART LNs. Our data highlight cellular and molecular factors that could regulate both antibody responses and viral reservoir persistence in PLWH.

immunology↗

Multi-Omics Clustering Differentiates the Total and Intact HIV Reservoirs and Related Host Immune Mechanisms

HIV reservoirs are heterogeneous across individuals, yet host determinants of this variability remain unclear. Applying multi-omics clustering to 1,230 people with HIV, integrating omics and functional data from circulating immune cells (transcriptomics, DNA methylation, immune phenotyping, ex-vivo cytokine production capacity), plasma proteomics, and CD4+ T-cell reservoir measurements (total and intact HIV-DNA copies), revealed three immunologically distinct endotypes: All Low (low total/low intact reservoir size), All High (high total/high intact reservoir size) and Mixed (high total/low intact reservoir size). Per endotype, distinct immune landscapes were noticed in single-layer analyses as well as differences in clinical signatures. Applying non-linear machine learning across all layers, key predictors not captured by linear single-layer approaches showed IFN-{gamma} production and TCF7/AK5 expression across T-cell and NK-cell populations as well as IL-1{beta}/MCP-1 production after 24h stimulation and MAN1C1/EDAR expression on T-cell populations, linked to intact and total reservoir size, respectively. This host-virus integrative multi-omics framework provides a systems-level resource that may help to personalize reservoir-reducing intervention studies aiming for HIV cure and/or comorbidity reductions. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=111 SRC="FIGDIR/small/734029v4_ufig1.gif" ALT="Figure 1"> View larger version (37K): org.highwire.dtl.DTLVardef@16fded7org.highwire.dtl.DTLVardef@18f2e69org.highwire.dtl.DTLVardef@12ffc9borg.highwire.dtl.DTLVardef@17127cc_HPS_FORMAT_FIGEXP M_FIG a) Multi-omics clustering of 1,230 virally suppressed PLHIV identified three immunologically distinct endotypes: All Low (n=428), Mixed (n=483), and All High (n=280), with distinct total and intact HIV reservoir sizes. b) Single-layer analyses reveal characteristic immune landscapes: All Low Th1-skewed, naive T cells (immunophenotyping), high IFN-{gamma} production (7-day), downregulated Type I IFN pathways (bulk transcriptome); Mixed intermediate Th1/Th2, CD8 and CD4 effector memory T cells (immunophenotyping), IL-5 production (7-day), downregulated Type I IFN pathways (bulk transcriptome); All High Th2-skewed, CD4 effector memory T cells (immunophenotyping), high IL-5 production (7-day), upregulated Type I IFN pathways (bulk transcriptome). c) Endotypes carry distinct comorbidity burdens: All Low lower carotid plaque, AIDS-defining malignancies, and residual viremia; Mixed intermediate burden; All High highest carotid plaque, AIDS-defining malignancies, opportunistic infections, and residual viremia. d) Non-linear classification models (XGBoost) prioritize top host predictive markers: IFN-{gamma} response (7-day), TCF7 and AK5 expression in CD4/CD8 T-cells and NK-cells (characterize All Low; IL-1 response (24-hour), MAN1C1 and EDAR in CD4/CD8 T-cells, and MCP1 response (24-hour) characterize All High. Created in BioRender. C_FIG

immunology↗

Viral persistence and antiretroviral therapy shape systemic immune aging in treated HIV infection

Chronic infections can reshape immune system homeostasis, yet how persistent viral infections influence immune aging remains poorly understood. People living with HIV provide a unique model to investigate how long-term viral persistence affects immune aging despite effective antiretroviral therapy. Here, we characterize immune aging by integrating plasma proteomics with epigenetic and transcriptional profiles of circulating immune cells across large cohorts of treated individuals with HIV. We find that immune aging is markedly accelerated compared with healthy individuals and parallels established DNA methylation-based aging clocks. Accelerated immune aging is strongly associated with signatures of immunosenescence and correlates with the size of the latent HIV reservoir, suggesting a persistent imprint of viral persistence on immune aging trajectories. Notably, exposure to specific antiretroviral agents, particularly nucleoside reverse transcriptase inhibitors, is associated with reduced immune aging and suppression of age-associated immune gene programs. Together, these findings identify chronic viral persistence as a driver of systemic immune aging and indicate that antiretroviral therapy can partially modulate immune aging programs.

immunology↗

Broadly neutralizing antibody-secreting CAR-T cells elicit Fc-mediated effector functions in vitro and suppress HIV in humanized mice

Despite significant advances in antiretroviral therapy (ART) that have transformed human immunodeficiency virus (HIV) infection from a fatal diagnosis to a manageable chronic condition, the persistent viral reservoir necessitates lifelong treatment underscoring the critical need for curative interventions. Viral persistence within anatomically distinct reservoirs, coupled with HIV-associated immune dysregulation accentuates the need for innovative combination immunotherapies that can act through multiple mechanisms. We introduce the Hybrid chimeric antigen receptor (CAR) platform: a dual-function immunotherapy that combines the targeted cytotoxicity of CAR-T cells with the secretion of broadly neutralizing antibodies (bNAbs). This approach enables direct elimination of HIV-infected cells, neutralization of free virus and Fc-mediated effector recruitment. In vitro, Hybrid CAR-T cells eliminated HIV-infected CD4+ T cells while the secreted bNAbs neutralized HIV and mediated robust Fc-effector functions including antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP). In humanized mice, Hybrid CAR-T treatment achieved more than a 9-fold reduction in plasma viremia, accompanied by a significant decrease in viral levels across tissues, with circulating bNAbs detected in plasma. Collectively, these findings highlight the potential of Hybrid CAR-T cells as a synergistic next-generation therapeutic that bridges cellular and humoral immunity, supporting their translational promise as a strategy toward functional HIV cure.

immunology↗

Integrative assessment of total and intact HIV-1 reservoir by a five-region multiplexed Rainbow digital PCR assay

Persistent latent reservoirs of intact HIV-1 proviruses, capable of rebounding despite suppressive ART, hinder efforts towards an HIV-1 cure. Hence, assays specifically quantifying intact proviruses are crucial to assess the impact of curative interventions. Clinical trials have utilized two recent assays: intact proviral DNA assay (IPDA) and Q4PCR. While IPDA is more sensitive due to amplifying short fragments, it may overestimate intact fractions by relying only on two small regions. Q4PCR is sequencing-based and its performance might be subjected to bias against full-length proviruses. Leveraging digital PCR (dPCR) advancements, we developed the Rainbow 5-plex proviral HIV-1 DNA assay, assessing it with standard materials and samples from 69 PLWH. The Rainbow assay proved equally sensitive but more specific than IPDA, is not subjected to bias against full-length proviruses, enabling high-throughput quantification of total and intact reservoir size. This innovation offers potential for targeted evaluation and monitoring of rebound-competent reservoirs, contributing to HIV-1 management and cure strategies. TeaserThe 5 color HIV-1 Rainbow digital PCR assay offers a multi-level view on the HIV reservoir in one snapshot reaction.

molecular biology↗

A truncated HIV Tat demonstrates potent and specific latency reversal activity

A major barrier to HIV-1 cure is caused by the pool of latently infected CD4 T-cells that persist under combination antiretroviral therapy (cART). This latent reservoir is capable of producing replication-competent infectious virus once prolonged suppressive cART is withdrawn. Inducing the reactivation of HIV-1 gene expression in T-cells harboring a latent provirus in people living with HIV-1 under cART will likely result in depletion of this latent reservoir due to cytopathic effects or immune clearance. Studies have investigated molecules that reactivate HIV-1 gene expression but to date no latency reversal agent has been identified to eliminate latently infected cells harboring replication-competent HIV in cART treated individuals. Stochastic fluctuations in HIV-1 tat gene expression have been described and hypothesized to allow the progression into proviral latency. We hypothesized that exposing latently infected CD4+ T-cells to Tat would result in effective latency reversal. Our results indicate the capacity of a truncated Tat protein and mRNA to reactivate HIV-1 in latently infected T-cells ex vivo to a similar degree as the protein kinase C agonist: Phorbol 12-Myristate 13-Acetate, without T-cell activation nor any significant transcriptome perturbation.

cell biology↗

HIV-PULSE: A long-read sequencing assay for high-throughput near full-length HIV-1 proviral genome characterization

A deep understanding of the composition of the HIV-1 reservoir is necessary for the development of targeted therapies and the evaluation of curative efforts. However, current near full-length (NFL) HIV-1 proviral genome sequencing assays are based on labor-intensive and costly principles of repeated PCRs at limiting dilution, restricting their scalability. To address this, we developed a high-throughput, long-read sequencing assay called HIV-PULSE (HIV Proviral UMI-mediated Long-read Sequencing). This assay uses unique molecular identifiers (UMIs) to tag individual HIV-1 genomes, allowing for the omission of the limiting dilution step and enabling long-range PCR amplification of many NFL genomes in a single PCR reaction, while simultaneously overcoming poor single-read accuracy. We optimized the assay using HIV-infected cell lines and then applied it to blood samples from 18 individuals living with HIV on antiretroviral therapy, yielding a total of 1,308 distinct HIV-1 genomes. Benchmarking against the widely applied Full-Length Individual Proviral Sequencing assay revealed similar sensitivity (11% vs 18%) and overall good concordance, though at a significantly higher throughput. In conclusion, HIV-PULSE is a cost-efficient and scalable assay that allows for the characterization of the HIV-1 proviral landscape, making it an attractive method to study the HIV-1 reservoir composition and dynamics.

molecular biology↗

HIV-linked gut dysbiosis associates with cytokine production capacity in viral-suppressed people living with HIV

People living with HIV (PLHIV) are exposed to chronic immune dysregulation, even when virus replication is suppressed by antiretroviral therapy (ART). Given the emerging role of the gut microbiome in immunity, we hypothesized that the gut microbiome may be related to the cytokine production capacity of PLHIV. To test this hypothesis, we collected metagenomic data from 143 ART-treated PLHIV and assessed the ex vivo production capacity of eight different cytokines (IL-1{beta}, IL-6, IL-1Ra, IL-10, IL17, IL22, TNF and IFN-{gamma}) in response to different stimuli. We also characterized CD4+ T cell-counts, HIV reservoir and other clinical parameters. Compared to 190 age- and sex-matched controls and a second independent control cohort, PLHIV showed microbial dysbiosis that was correlated with viral reservoir levels, cytokine production capacity and sexual behavior. Notably, we identified two genetically different P. copri strains that were enriched in either PLHIV or healthy controls. The control-enriched strain was negatively associated with IL-10, IL-6 and TNF production, independent of age, sex and sexual behavior, and positively associated with CD4+ T cell-level, whereas the PLHIV-enriched strain showed no associations. Our findings suggest that modulating the gut microbiome may be a strategy to modulate immune response in PLHIV. Novel PointsO_LIWe identified compositional and functional changes in the gut microbiome of PLHIV that were strongly related to sexual behavior. C_LIO_LIHIV-associated bacterial changes are negatively associated with HIV reservoir. The relative abundance of Firmicutes bacterium CAG 95 and Prevotella sp CAG 5226 both show a negative association with CD4+ T cell-associated HIV-1 DNA. C_LIO_LIPrevotella copri and Bacteroides vulgatus show association with PBMC production capacity of IL-1{beta} and IL-10 that is independent of age, sex, BMI and sexual behavior. C_LIO_LIWe observed two genetically different P. copri strains that are enriched in PLHIV and healthy individuals, respectively. C_LIO_LIThe control-related P. copri strain specifically shows a negative association with IL-10, IL-6 and TNF production and a positive association with CD4+ T cell-level. This suggests it plays a potential protective role in chronic inflammation, which may be related to enrichment of a specific epitope peptide. C_LI

microbiology↗

In-depth single-cell analysis of translation-competent HIV-1 reservoirs identifies cellular sources of plasma viremia

Clonal expansion of HIV-infected cells contributes to the long-term persistence of the HIV reservoir in ART-suppressed individuals. However, the contribution to plasma viremia from cell clones that harbor inducible proviruses is poorly understood. Here, we describe a single-cell approach to simultaneously sequence the TCR, integration sites and proviral genomes from translation-competent reservoir cells, called STIP-Seq. By applying this approach to blood samples from eight participants, we showed that the translation-competent reservoir mainly consists of proviruses with short deletions at the 5-end of the genome, often involving the major splice donor site. TCR and integration site sequencing revealed that antigen-responsive cells can harbor inducible proviruses integrated into cancer-related genes. Furthermore, we found several matches between proviruses retrieved with STIP-Seq and plasma viruses obtained during ART and upon treatment interruption, showing that STIP-Seq can capture clones that are responsible for low-level viremia or viral rebound.

microbiology↗

In-depth characterization of HIV-1 reservoirs reveals links to viral rebound during treatment interruption

The HIV-1 reservoir is composed of cells harboring latent proviruses that are capable of contributing to viremia upon antiretroviral treatment (ART) interruption. Although this reservoir is known to be maintained by clonal expansion, the contribution of large, infected cell clones to residual viremia and viral rebound remains underexplored. Here, we conducted an extensive analysis on four ART-treated individuals who underwent an analytical treatment interruption (ATI). We performed subgenomic (V1-V3 env), near full-length proviral and integration site sequencing, and used multiple displacement amplification to sequence both the integration site and provirus from single HIV-infected cells. We found eight proviruses that could phylogenetically be linked to plasma virus obtained before or during the ATI. This study highlights a role for HIV-infected cell clones in the maintenance of the replication-competent reservoir and suggests that infected cell clones can directly contribute to rebound viremia upon ATI.

microbiology↗