CROI 2019 Abstract eBook

Abstract eBook

Poster Abstracts

on cell metabolism and specific metabolic pathways could regulate T cell activation. We hypothesized that differences in metabolic profile could be used as biomarkers to further elucidate pathogenesis of IRIS. Methods: Non-targeted global metabolomic profiling was performed on plasma samples derived from a perspective longitudinal study of 30 HIV patients (17 HIV non-IRIS and 13 HIV IRIS) at pre-ART (CD4 ≤ 100 cells/mm3), 1-month post-ART, and 12-month post-ART timepoints by Metabolon, Inc. Metabolites were identified by liquid chromatography/mass spectrometry followed by comparison to a reference library. Plasma cytokines were measured using Meso Scale multiplex cytokine detection kit then correlated with metabolic pathways via Spearman correlation. Results: A total of 832 metabolites were identified in plasma samples. Comparing HIV IRIS and HIV non-IRIS groups, more differentially expressed metabolites reaching statistically significance ((p≤0.05) were identified at pre-ART and 1-month post-ART time points than the 12-month post-ART time point. Lipid and amino acid metabolites composed the majority of the compounds that achieved statistical significance. The IRIS group had significantly higher levels of select acylcarnitines, and lower levels of plasmalogen and phosphatidylcholine at pre-ART. Amino acids including tryptophan, glutamate, glycine, and tyrosine metabolismwere found to be differentially expressed in IRIS and non-IRIS groups at pre-ART and 1-month post-ART. Spearman correlations revealed that glutamate metabolismwas positively correlated with TNF, while tryptophan and glycine metabolismwere negatively correlated with IL-10, and D-dimer respectively in the IRIS group at pre-ART. Conclusion: HIV+ persons who develop IRIS have a distinct metabolic profile with perturbed lipid and amino acid metabolism that is associated with known inflammatory mediators of IRIS. These data suggest that evaluation of immunometabolism and its role in inflammation associated with IRIS warrants further investigation. 217 EXTRACELLULAR VESICLE–ASSOCIATED CYTOKINES IN HIV-INFECTED HUMAN EX VIVO TONSILS Vincenzo Mercurio 1 , Wendy Fitzgerald 2 , Leonid Margolis 2 1 University of Milan, Milan, Italy, 2 National Institute of Child Health and Human Development, Bethesda, MD, USA Background: Cytokines play an important role in HIV infection. Some of these cytokines are associated with extracellular vesicles (EVs) either on their surface or being encapsulated. Here, we investigated the modulation of EV-associated cytokines during HIV infection and antiretroviral therapy (ART) in human ex vivo tonsils. Methods: Ex vivo tonsils were infected with HIV-1 strains, X4-LAI04 or R5- SF162. HIV was either allowed to replicate for 15 days, or tissues were treated with ART (3TC and AZT) at day 2 post-infection. 33 cytokines in soluble or EV- associated forms were evaluated with multiplexed bead-based assays. Results: Early in HIV infection there was a significant increase in soluble IFNα, MCP-1, MIG, MIP-1α, MIP-1β, RANTES, and TNFα. EV-associated cytokines that significantly increased were IL-13, IP-10, and MIP-1β for X4, and MIP-1α, MIP-1β, and RANTES for R5. In addition to increased concentrations, some cytokines also shifted their distribution: MIP-1α and MIP-1β to a higher percentage in EV-associated form, and RANTES to more soluble. In cumulative analyses, in X4-infected tissues there was an increase in the release of soluble IL-2, IL-21, IFNα, MIP-1α, MIP-1β, RANTES, and TNFα, and decrease of TGF-β. R5 infection increased tissue production of MIP-1α, MIP-1β, and RANTES. X4 significantly increased total EV-associated IL-2, IL-7, IFNα, M-CSF, MIP-1α, MIP-1β, RANTES; R5 infection led to increased EV-associated IL-2 and RANTES. ART treatment halted HIV-1 replication, but most cytokine levels remained similar to those in HIV-infected controls, including MIP-1α, MIP-1β, and RANTES. In X4-infected tonsils treated with ART there was a significant decrease in only soluble IL-7, IP-10, and MIG, and an increase in IL-6; in R5-infected tissues treated with ART there was a decrease in soluble IL-1α, IL-1β, IL-16, IL-17, IL-18, MIG, and MIP-3α. ART treatment restored the levels of some soluble cytokines but did not restore EV-associated cytokines. Conclusion: Cytokine levels increased during HIV infection in both soluble and EV associated forms. Cytokines most upregulated by HIV did not decrease even after 13 days of ART. The most affected EV-associated cytokines were chemokines, which were not restored by ART. ART-treated ex vivo infected human tissues provide a newmodel to study tissue activation after HIV

replication is suppressed. These studies will assist in desiphering mechanisms of pathologies that develop in ART-treated patients. 218 MASSIVE RELEASE OF PLATELET-DERIVED EXTRACELLULAR VESICLES DURING HIV INFECTION Eva Poveda 1 , Andrés Tabernilla 2 , Marta Grandal 3 , Alexandre Pérez 4 , Ángel Salgado 1 , Hortensia Álvarez 5 , Ana Mariño 5 , Nieves Valcarce 5 , Juan González- García 6 , Félix Gutiérrez 7 , Manuel Crespo 4 , Ezequiel Ruiz-Mateos 8 , Michael M. Lederman 9 , Michael L. Freeman 9 , for the ECRIS integrated in the Spanish AIDS Research Network 1 Galicia Sur Health Research Institute, Vigo, Spain, 2 Complexo Hospitalario Universitario A Coruña, A Coruña, Spain, 3 Instituto de Investigación Biomédica de A Coruña, A Coruña, Spain, 4 Complejo Hospitalario Universitario de Vigo, Vigo, Spain, 5 Hospital Arquitecto Marcide, Ferrol, Spain, 6 La Paz University Hospital, Madrid, Spain, 7 Hospital General Universitario de Elche, Elche, Spain, 8 Institute of Biomedicine of Seville, Sevilla, Spain, 9 Case Western Reserve University, Cleveland, OH, USA Background: Extracellular Vesicles (EVs) derived from different cell types by ectocytosis (microvesicles) or endocytosis (exosomes) may serve as intercellular messengers in pathogenic processes. Circulating mitochondrial DNAs (mtDNA) are potent danger-associated molecular patterns (DAMPs) found in inflammatory diseases including viral infections. We evaluate the EVs profile and plasma mtDNA levels in a well-characterized cohort of HIV-infected patients and controls. Methods: Plasma samples from HIV-infected patients from the HIV Biobank- Spanish HIV/AIDS Network and 2 hospitals in Galicia were selected. Five groups were defined: 1) treatment-ART; 2) receiving ART with non-detectable viremia (ND) > 1 year); 3) elite controllers (EC) (<50 copies/mL without ART > 1 year); 4) viremic controllers-VC (HIV-RNA >50 and < 2000 copies/mL without ART for more than 1 year); and 5) a control group of HIV negatives. EVs (<1μm, CD9+) were quantified and characterized by flow cytometry using monoclonal antibodies targeting their source CD61/CD41 for platelets; CD16/CD11b for neutrophils. MitoTrackerDeepRed identified EVs containing mitochondria. mtDNA was quantified using a quantitative real-time PCR assay. Results: 120 HIV-infected patients (30 naïve, 30 ND, 30 EC, and 30 VC) and 30 controls were included. The table shows the main characteristics of the study population and results. EVs numbers were expanded at least 10 fold in all HIV-infected groups compared to controls’ counts. Most EV had platelet markers (>79%) within the HIV groups, and few had neutrophil markers (< 2%). A minority of platelet-derived EVs contained mitochondria, but most neutrophil- derived EVs did. Mitochondria+ EV were less frequent for those on ART than in other HIV+ groups. A positive correlation was found between the number of platelet-derived mitochondria+ EVs and total plasma mtDNA levels (rho=0.727; p<0.001) but not for neutrophil-derived mitochondria+ EVs. Mitochondrial density (MFI) was greater in controls’ EVs than in HIV-infected groups, lowest levels for those on ART. Conclusion: A massive release of platelet-derived EVs occurs during HIV infection regardless of HIV status. EVs count correlates with plasma mtDNA levels. HIV infection and ART both appear to diminish mitochondrial density in EVs yet as EVs numbers are expanded, total mitochondrial levels in plasma are preserved in HIV infection or increased. The mechanisms underlying these perturbations in EVs levels and the mitochondria within them in HIV infection are not known.

Poster Abstracts

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CROI 2019