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Matzaraki, V.

Publications and source records attributed to Matzaraki, V..

4 recordsLinked to original sources

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↗

Fatty acid desaturation and lipoxygenase pathways support trained immunity

Infections and vaccinations can induce long-term enhanced responses of innate immune cells to heterologous stimuli, establishing a de facto innate immunological memory termed trained immunity. Monocytes exposed to the Bacillus Calmette-Guerin (BCG) vaccine, have a trained immunity phenotype, characterized by an increased biosynthesis of different lipid mediators (LMs) derived from long-chain polyunsaturated fatty acids (PUFAs). Pharmacological and genetic approaches showed that long-chain PUFA synthesis and lipoxygenase (LOX)-derived LMs are crucial for the BCG trained immunity responses of human monocytes. Furthermore, monocytes of healthy individuals vaccinated with BCG are enriched in 12-LOX products. The elucidation of the lipid metabolic pathways that promote innate immune memory contributes to our understanding of trained immunity and may help identify therapeutic tools and targets for the modulation of innate immune responses.

immunology↗

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↗