CROI 2024 Abstract eBook

Abstract eBook

Poster Abstracts

RANKL. Meanwhile, IL-32α induces the differentiation of osteoclasts. This novel demonstration of the role of IL-32 in regulation of calcium metabolism suggests that it may constitute a common, upstream cause to patterns of bone and heart disease observed in PLWH. Myocardial Gene Profiling at Time of Sudden Death Demonstrates Increased Immune Responses in PWH Tasha Tsao 1 , David P. Maison 1 , Brian H. LaFranchi 1 , James Salazar 1 , Arianne Caudal 2 , Brielle Kinkead 1 , Kosuke Nakasuka 1 , Ellen Moffat 1 , Andrew J. Connolly 1 , Timothy J. Henrich 1 , Zian H. Tseng 1 1 University of California San Francisco, San Francisco, CA, USA, 2 Stanford University, Stanford, CA, USA Background: People with HIV (PWH) are at increased risk of sudden cardiac death (SCD). In our HIV Postmortem Systematic Investigation of Sudden Cardiac Death (POST SCD) Study we showed that PWH have higher interstitial myocardial fibrosis, a substrate for fatal cardiac arrhythmias causing SCD. However, the reason(s) for this increase are unknown. The myocardial transcriptome can reflect the acute cellular alterations for these lethal arrhythmias. We leveraged our POST SCD cohort to compare gene expression in myocardium from people with and without HIV infection. Methods: We performed transcriptomic evaluation on left ventricular myocardium sampled at the time of SCD or traumatic death from 245 cases, 20 from PWH, using a Nanostring nCounter panel of 450 curated genes with potential association with SCD. We compared myocardial transcripts from PWH, most of whom were on ART, to 3 uninfected control groups: 1) demographic matched (N=60); 2) cause-of-sudden-death matched (N=20); 3) immediate traumatic deaths (N=11). Gene expression and ontology analyses were performed. Results: We found a significant increase in myocardial expression of CD16 (NK and myeloid immune cell marker) in PWH compared to all 3 uninfected control sudden deaths: demographic, cause-of-death-matched, and immediate traumatic deaths. Moreover, significant increases in myocardial expression of genes related to innate immune response (CD31/PCAM), extracellular matrix homeostasis (MMP9), DNA damage/apoptosis, and leukocyte-endothelial interactions were observed in PWH compared to uninfected cause-of-death matched controls. Myocardial CD45 expression was also significantly increased in PWH compared with demographic matched HIV- controls. Statin use did not alter myocardial gene expression in HIV+ SCD. Conversely, collagen-related genes and heart failure markers (ANP/BNP) were downregulated in myocardium from HIV+ SCD compared to that from all 3 HIV- control groups. Conclusion: RNA profiling from myocardium sampled at time of SCD demonstrates increased immune activity but lower expression of genes associated with heart failure in PWH compared to uninfected control sudden deaths. Fibrosis-related genes were also downregulated in HIV+ myocardium, possibly because PWH already had higher levels of pre-existing fibrosis at the time of sudden death. These data suggest that increased risk of SCD in PWH may involve a multi-hit process of increased myocardial immune processes on top of previously established interstitial fibrosis. Factors Affecting Risk of Major Adverse Cardiovascular Events Among People With HIV in REPRIEVE Markella V. Zanni 1 , Maya Watanabe 2 , Heather J. Ribaudo 2 , Gerald S. Bloomfield 3 , Kathleen V. Fitch 1 , Carl J. Fichtenbaum 4 , Triin Umbleja 2 , Judith S. Currier 5 , Judith A. Aberg 6 , Carlos D. Malvestutto 7 , Marissa Diggs 1 , Michael T. Lu 1 , Pamela S. Douglas 3 , Steven K Grinspoon 1 , for the REPRIEVE Investigators 1 Massachusetts General Hospital, Boston, MA, USA, 2 Harvard TH Chan School of Public Health, Boston, MA, USA, 3 Duke University School of Medicine, Durham, NC, USA, 4 University of Cincinnati, Cincinnati, OH, USA, 5 University of California Los Angeles, Los Angeles, CA, USA, 6 Mt Sinai School of Medicine, New York, NY, USA, 7 The Ohio State University, Columbus, OH, USA Background: People with HIV (PWH) have a 2-fold increased risk of major adverse cardiovascular events (MACE). REPRIEVE showed pitavastatin reduced MACE by 35% among PWH with low-to-moderate traditional risk. Enhanced understanding of the relative contributions of traditional and HIV-specific risk factors (RF) to MACE may guide concomitant individual- and population-level preventive interventions. Methods: Analyses in the REPRIEVE population were performed for first MACE (including MI, TIA/stroke, revascularization, CV death), with median follow-up of 5.6 years through August 2023. Cox proportional hazards models stratified by randomized treatment group were used to account for treatment differences. Individual models adjusting for each entry RF were fit, and the strongest factors were then combined into a single multivariate adjusted model.

activation and differentiation of monocyte-derived macrophages (MDMs). We assessed the gene expression by RNAseq and cellular metabolism of MDMs (Seahorse) and responsiveness of these cells to bacterial products (LPS, Pam3CysSerLys4, or flagellin). We performed spatial profiling of arterial blood vessels from PWH and people without HIV (PWoH) using NanoString's GeoMx. Cells within vessels were stained for CD14 and CD163. Results: PWH had increased CAC scores (350 vs 18; p=0.04) compared to PWoH, and among PWH vascular ages were higher than their biological ages (77y vs 55y; p<0.0001). Increasing CAC was associated with elevated inflammatory markers (osteopontin, C-reactive protein, IL6, soluble CD14; P<0.02). MDMs from PWH had altered gene expression in response to bacterial products, including higher HIF1α, mTOR, AKT1, MyD88 and NFκB, and were more dependent on glycolysis, all hallmarks of innate trained immunity. Spatial profiling confirmed increased macrophage infiltration into vessel walls in PWH. Pathway analysis of coronary arteries from PWH vs PWoH showed increased enrichment of glycolysis, TLR signaling, AKT, IGF1 and MTOR pathways. A cross-sectional comparison of regions of interest (ROI) with highest infiltration showed TLR4 and CD163 was higher in PWH. In ROI with lower infiltration, higher expression of FABP12 and CD163 was found in tissues from PWH. Analysis of pathways driving higher infiltration in both donor types identified unique pathways in PWH including innate immunity, TLR cascade, oxidative stress induced senescence, cellular response to hypoxia, and O2-dependent proline hydroxylation of HIF1α. Conclusion: Increased CVD risk in PWH may be driven by trained immunity as evidenced by immune functional profiling of blood-derived MDMs and spatial profiling of macrophages within blood vessel walls. The figure, table, or graphic for this abstract has been removed. IL-32 Isoforms Potentially Impact Bone and Cardiovascular Diseases in HIV Infection Hardik Ramani 1 , Madeleine Durand 1 , Aurelie Cleret-Buhot 1 , Remi Bunet 1 , Carl Chartrand-Lefebvre 1 , Benoit Trottier 2 , Réjean Thomas 3 , Jean-Pierre Routy 4 , Claude Fortin 1 , Valérie Martel-Laferriére 1 , Alan Landay 5 , Mohammad-Ali Jenabian 6 , Mohamed El-Far 1 , Cécile Tremblay 1 1 Centre de Recherche du CHUM, Montreal, Canada, 2 Clinique Médicale du Quartier Latin, Montreal, Canada, 3 Clinique Médicale l'Actuel, Montreal, Canada, 4 McGill University Health Centre, Montreal, Canada, 5 Rush University Medical Center, Chicago, IL, USA, 6 Université du Québec à Montréal, Montreal, Canada Background: We have recently demonstrated that the multi-isoform proinflammatory cytokine IL-32 is upregulated by HIV infection and is associated with subclinical CVD in people living with HIV (PLWH). However, mechanisms by which IL-32 isoforms contribute to the pathogenesis of CVD and potentially other chronic diseases like osteoporosis remain unclear. We investigated the impact of IL-32 isoforms α, β and γ on the differentiation of human mesenchymal stem cells (hMSC) and primary human monocytes into osteoblasts or osteoclasts (cells involved in calcium deposition and bone formation or bone resorption, respectively). These cells are involved in processes that are known to be dysregulated in PLWH in the bone (increased osteoporosis) and in the heart (increased non-calcified, vulnerable atherosclerotic plaque). We hypothesize that alterations in IL-32 isoforms seen in PLWH may be a common cause for bone and heart disease seen in that population. Methods: Human CD14+CD16- monocytes or hMSC (osteoblasts precursors) were stimulated with recombinant IL-32 isoforms α, β or γ at 500 ng/ml with or without the osteoclast differentiation factor RANKL (30ng/ml) for 21 days. Immunofluorescence imaging on Spinning-Disc Zeiss AxioObserver was used to identify and analyze the differentiated cells. Results: Both IL-32β and IL-32γ but not IL-32α induced the differentiation of hMSC as well as the primary monocytes into osteocalcin+ osteoblast cells. In contrast, IL-32α but not IL-32β or IL-32γ significantly induced the differentiation of a subset of primary CD14+CD16- monocytes into the giant multi-nucleated osteoclasts with the typical expression of the F-actin ring and TRAcP (p<0.0001). Interestingly, when either IL-32β or IL-32γ were combined with RANKL (a typical inducer of osteoclasts), these IL-32 isoforms counteracted the effect of RANKL and maintained their function by inducing osteoblast differentiation from monocytes (p<0.0001 and p=0.0001, respectively), further suggesting their dominant role in osteoblastogenesis. Conclusion: Our data reveal a new function for IL-32 isoforms β and γ (the longest IL-32 isoforms) in inducing the differentiation of primary monocytes into osteocalcin+ osteoblasts by counteracting the osteoclast activation factor

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