CROI 2024 Abstract eBook

Abstract eBook

Poster Abstracts

969

Activated Proinflammatory NK Cells Promote Atherogenesis in Adolescents w/ Perinatally Acquired HIV Mario J Alles 1 , Manuja G. Gunasena 1 , Victor Musiime 2 , Cissy Kityo 3 , Banumathi Tamilselvan 4 , Brian Richardson 4 , Wendy Ching-Wen Li 4 , Cheryl Cameron 4 , Mark Cameron 4 , Sahera Dirajlal-Fargo 5 , Nicholas Funderburg 1 , Namal P. Liyanage 1 1 The Ohio State University, Columbus, OH, USA, 2 Makerere University, Kampala, Uganda, 3 Joint Clinical Research Centre, Kampala, Uganda, 4 Case Western Reserve University, Cleveland, OH, USA, 5 Northwestern University, Chicago, IL, USA Background: Perinatally acquired HIV (PHIV) and lifelong antiretroviral therapy (ART) may alter the development and function of the immune system. Published literature and our preliminary data suggest reprogramming of innate immune cells may accelerate aging and increase the risk for future end-organ complications, including cardiovascular disease (CVD). Natural killer (NK) cells are a heterogeneous group of innate immune cells with divergent functions; little is known about the role of NK cells in HIV-associated atherogenesis. Methods: In this cross-sectional study, using high dimensional flow cytometry, plasma biomarker profiling, and transcriptomics, we compared immune signatures in cryopreserved peripheral blood mononuclear cells and cardiovascular biomarkers in Ugandan adolescents with PHIV on ART (n=18), and age/sex-matched HIV-unexposed and uninfected adolescents (n=20). Statistical comparisons employed the Mann-Whitney U test, with significance at p< 0.05. We explored the connection between immune signatures and plasma biomarkers using the Pearson correlation coefficient. Results: The median age was 14 years, and 50% were females and all PHIVs were virally suppressed (HIV1 RNA< 50c/mL). Among PHIVs, markers of activation (CD69, HLA-DR, NKp44), maturation and memory (CD57), and migration to inflamed tissue (CXCR3) were elevated in most NK subsets (based on CD56 and CD16 expression) compared to levels in HIV- (p<0.05 for all). Oxidized LDL (ox-LDL) levels were significantly lower in the plasma of PHIVs (p<0.05). Further, negative correlations were found between most of the activated NK subsets expressing chemokine receptor CCR5 and plasma ox-LDL among PHIVs (p<0.05 for all). Our in vitro studies confirmed increased uptake of ox-LDL by macrophages in the presence of activated NK cells (p<0.05). Bulk-RNA sequencing data revealed differential expression of genes associated with immune cell migration, cholesterol uptake into tissue, vascular remodeling, and enrichment of pathways associated with NK activation and epigenetic regulation in the PHIV group (p<0.05). Conclusion: Our data demonstrate, for the first time, increased expression of several activated, mature NK subsets with the potential to home to vascular tissue and influence increased uptake of plasma ox-LDL into vessel wall macrophages and initiate atherogenesis in adolescents with PHIV. We are currently performing mechanistic and longitudinal studies to confirm these findings. DNA Methylation Signatures of Inflammation in Youth Living With Perinatally-Acquired HIV Stephanie Shiau 1 , Sean Brummel 2 , Jasmine Douglas 1 , Francesca Zumpano 1 , Michael J. Corley 3 , Jennifer Jao 4 , Murli Purswani 5 , Kunjal Patel 2 , Carmen Marsit 6 , for the Pediatric HIV/AIDS Cohort Study (PHACS) 1 Rutgers University, Piscataway, NJ, USA, 2 Harvard TH Chan School of Public Health, Boston, MA, USA, 3 Weill Cornell Medicine, New York, NY, USA, 4 Northwestern University, Chicago, IL, USA, 5 Bronx Lebanon Hospital Center, Bronx, NY, USA, 6 Emory University, Atlanta, GA, USA Background: Epigenetic modifications may highlight mechanisms through which HIV and antiretroviral therapy (ART) exposure during critical developmental periods affect biological pathways and disease risk. We examined if perinatally-acquired HIV is associated with genome-wide alterations in the DNA methylome by comparing youth living with perinatal HIV (YPHIV) and youth who are perinatally HIV-exposed uninfected (YPHEU) at two timepoints. Among YPHIV, we examined associations between viral load (VL), CD4 count, and markers of inflammation with genome-wide alterations in the DNA methylome. Methods: 32 YPHIV and 7 YPHEU with peripheral blood mononuclear cell samples collected at two timepoints ≥3 years apart were selected from the US-based PHACS Adolescent Master Protocol. DNA methylation was assayed using the Illumina MethylationEPIC (850K) array. Using the limma package, we tested for differentially methylated (DM) CpG sites (FDR p-value <0.05 and ≥5% difference in methylation) between groups at each timepoint. 15 targeted genes identified from prior work (PMID: 31324826) were also assessed for DM CpG sites. Among YPHIV, genome-wide associations of cumulative VL,

(CD14+CD6- and CD14+CD16+% monocytes; CD8 expressing CD38 and HLA DR, p≤0.037); higher systolic blood pressure (p=0.040), and higher increases in PWV over 96 weeks (p=0.047). In mixed linear regression models adjusting for HIV status, age, gender, physical activity (met-kcal/hour), mean PHQ-9 score, monocytes, activated CD8 T cells, total ACE score (β=0.10) and HHDYS (β=-0.09) remained associated with a higher change in PWV over 96 weeks. Conclusion: Findings suggest that ACEs may contribute to CVD risk in YPHIV in Uganda, even after adjusting for factors known to influence cardiovascular health. Early life stress may play an important role on inflammation and cardiovascular health in this setting. Further research is warranted to determine the impact of emotional events on physical outcomes in HIV, whether this is a potentially modifiable risk factor, and how to mitigate long-term consequences.

968

Changes in the Lipidome Are Associated With Immune Activation in Ugandan PHIV Sahera Dirajlal-Fargo 1 , Melica Nikahd 2 , Kate Ailstock 2 , Manjunath Manubolu 2 , Victor Musiime 3 , Grace A. McComsey 4 , Nicholas Funderburg 2 1 Ann & Robert H Lurie Children's Hospital of Chicago, Chicago, IL, USA, 2 The Ohio State University, Columbus, OH, USA, 3 Joint Clinical Research Centre, Kampala, Uganda, 4 Case Western Reserve University, Cleveland, OH, USA Background: Lipidomics, the analysis of the composition and concentrations of lipid classes and species, may provide greater mechanistic insight into the basis of cardiovascular disease (CVD). This study examined the changes in the lipidome and associations with immune activation in youth living with perinatally acquired HIV (PHIV). Methods: The serum lipidome, including 850 different lipid species across 13 lipid classes, as well as the fatty acid composition of these molecules, was measured by direct infusion-tandem mass spectrometry from 100 ART-treated PHIV and 98 age- and sex-matched HIV- Ugandan children at baseline and 96 weeks. All participants were between 10-18 yrs of age. PHIVs had HIV-1 RNA level ≤50 c/mL. In addition, plasma markers of systemic inflammation (hsCRP, IL6), monocyte activation (sCD14 and sCD163), gut integrity and translocation (I-FABP and BDG) were measured by ELISA. T cell activation (expression of CD38 and HLA-DR on CD4+ and CD8+ T cells) was measured by flow cytometry. Comparisons of lipid concentrations between groups were evaluated using 2-sample t-test. Spearman correlations were used to assess correlations between changes in lipid concentration and immune activation. Results: Overall, median age [IQR] was 12 years [11-14]; 52% were females. In PHIV, median CD4+ cell counts were 988 cells/µL, and 85% had viral load <50 copies/mL throughout the study. Total cholesterol, LDL, and HDL were similar between the groups, however, the concentrations of ceramides, diacylglycerols, free fatty acids, lysophysophatidylcholines and phosphatidylcholines, were significantly higher in PHIV (P≤0.03). A network figure highlights the associations between changes in lipid species concentrations and inflammatory biomarkers over 96 weeks with a correlation >|0.4|. Notable trends included the predominant association with increases in unsaturated triacylglycerols with increase in activated CD4+ and CD8+ T cells and in fungal translocation, and with decreases in sCD14 and IFAB. Conclusion: Despite similar basic lipid panels as HIV-, virologically suppressed PHIV on ART have elevated lipid species that are known to be associated with CVD. Our network analysis identified that triacylglycerols with long and unsaturated acyl chains, previously shown to be associated with an increased risk of plaques in adults living with HIV, are associated with immune activation and fungal translocation. Further studies are warranted to determine whether these lipid species may serve as novel biomarkers. The figure, table, or graphic for this abstract has been removed.

Poster Abstracts

970

CROI 2024 308