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Interleukin 32 (IL-32) is a potent multi-isoform proinflammatory cytokine, which is upregulated in people with HIV (PWH) and is associated with cardiovascular disease (CVD) risk. However, the impact of IL-32 isoforms on CD4 T-cell cardiotropism, a mechanism potentially contributing to heart inflammation, remains unknown. Here we show that IL-32 isoforms β and γ induce the generation of CCR4+CXCR3+ double positive (DP) memory CD4 T-cell subpopulation expressing the tyrosine kinase receptor c-Met, a phenotype associated with heart-homing of T cells. Our ex vivo studies on PWH show that the frequency of DP CD4 T cells is significantly higher in individuals with, compared to individuals without, subclinical atherosclerosis and that DP cells from antiretroviral-naive and treated individuals are highly enriched with HIV DNA. Together, these data demonstrate that IL-32 isoforms have the potential to induce heart-homing of HIV-infected CD4 T cells, which may further aggravate heart inflammation and CVD in PWH. [ABSTRACT FROM AUTHOR]

Background: Persistent immune activation due to gut barrier dysfunction is a suspected cause of morbidity in HIV, but the impact of menopause on this pathway is unknown.Methods: In 350 women with HIV from the Women's Interagency HIV Study, plasma biomarkers of gut barrier dysfunction (intestinal fatty acid binding protein; IFAB), innate immune activation (soluble CD14 and CD163; sCD14, sCD163), and systemic inflammation (interleukin-6 and tumor necrosis factor receptor 1; IL-6, TNFR1) were measured at 674 person-visits spanning ≤2 years.Results: Menopause (post- vs premenopausal status) was associated with higher plasma sCD14 and sCD163 in linear mixed-effects regression adjusting for age and other covariates (β = 161.89 ng/mL; 95% confidence interval [CI], 18.37-305.41 and 65.48 ng/mL, 95% CI, 6.64-124.33, respectively); but not with plasma IFAB, IL-6, or TNFR1. In piece-wise linear mixed-effects regression of biomarkers on years before/after the final menstrual period, sCD14 increased during the menopausal transition by 250.71 ng/mL per year (95% CI, 16.63-484.79; P = .04), but not in premenopausal or postmenopausal periods.Conclusions: In women with HIV, menopause may increase innate immune activation, but data did not support an influence on the gut barrier or inflammation. Clinical implications of immune activation during menopausal transition warrant further investigation. [ABSTRACT FROM AUTHOR]

AIDS Clinical Trials Group study A5308 found reduced T-cell activation and exhaustion in human immunodeficiency virus (HIV) controllers start antiretroviral therapy (ART). We further assessed HIV-specific T-cell responses and post-ART viral loads. Before ART, the 31% of participants with persistently undetectable viremia had more robust HIV-specific T-cell responses. During ART, significant decreases were observed in a broad range of T-cell responses. Eight controllers in A5308 and the Study of the Consequences of the Protease Inhibitor Era (SCOPE) cohort showed no viremia above the level of quantification in the first 12 weeks after ART discontinuation. ART significantly reduced HIV-specific T-cell responses in HIV controllers but did not adversely affect controller status after ART discontinuation. [ABSTRACT FROM AUTHOR]

Background: A higher proportion of circulating memory CD4+ T cells is associated with prevalent diabetes mellitus in the general population. Given the broad changes in adaptive immunity, including memory T-cell expansion, and rising prevalence of diabetes in the human immunodeficiency virus (HIV) population, we assessed whether similar relationships were present in persons with HIV (PWH).Methods: Multiple CD4+ and CD8+ T-cell subsets were measured by flow cytometry, and prevalent diabetes cases were adjudicated by 2 physicians for PWH and HIV-negative participants in the Veterans Aging Cohort Study. Multivariable logistic regression models evaluated the association of T-cell subsets and diabetes stratified by HIV status, adjusted for cytomegalovirus serostatus and traditional risk factors.Results: Among 2385 participants (65% PWH, 95% male, 68% African American), higher CD45RO+ memory CD4+ T cells and lower CD38+ CD4+ T cells were associated with prevalent diabetes, and had a similar effect size, in both the PWH and HIV-negative (P ≤ .05 for all). Lower CD38+CD8+ T cells were also associated with diabetes in both groups.Conclusions: The CD4+ and CD8+ T-cell subsets associated with diabetes are similar in PWH and HIV-negative individuals, suggesting that diabetes in PWH may be related to chronic immune activation. [ABSTRACT FROM AUTHOR]

Background: Chronic inflammation is associated with AIDS-defining and non-AIDS-defining conditions. Limited research has considered how food insecurity influences chronic inflammation among people living with human immunodeficiency virus (HIV). We examined whether food insecurity was associated with higher levels of inflammation among women living with HIV (WWH) in the United States.Methods: We analyzed cross-sectional data collected in 2015 from 421 participants on antiretroviral therapy from the Women's Interagency HIV Study. The exposure was any food insecurity. The outcome was inflammation, measured by proinflammatory cytokine interleukin-6 (IL-6) and tumor necroses factor receptor 1 (TNFR1) levels. We conducted multivariable linear regressions, adjusting for sociodemographic, clinical, and nutritional factors.Results: Nearly one-third of participants (31%) were food insecure and 79% were virally suppressed (<20 copies/mL). In adjusted analyses, food insecurity was associated with 1.23 times the level of IL-6 (95% confidence interval [CI], 1.06-1.44) and 1.13 times the level of TNFR1 (95% CI, 1.05-1.21). Findings did not differ by HIV control (virally suppressed with CD4 counts ≥500 cells/mm3 or not) in adjusted stratified analyses.Conclusion: Food insecurity was associated with elevated inflammation among WWH regardless of HIV control. Findings support the need for programs that address food insecurity among WWH. [ABSTRACT FROM AUTHOR]

Background: We examined changes in soluble inflammatory cytokines and T-cell activation after antiretroviral therapy (ART) initiation in an AIDS Clinical Trials Group (ACTG) nested case-control study.Methods: Cases were 143 human immunodeficiency virus (HIV)-infected adults who developed a non-AIDS event; 315 controls remained event-free. Specimens were tested pre-ART, year 1 post-ART, and at the visit preceding the event. Conditional logistic regression evaluated the associations of biomarker changes with non-AIDS events.Results: Inflammatory and most activation biomarkers declined from pre-ART to year 1 for cases and controls. Subsequently, inflammatory biomarkers remained mostly stable in controls but not cases. Cellular activation markers generally declined for both cases and controls between year 1 and the pre-event sampling. Controls with greater pre-ART RNA levels or lower CD4+ levels had higher biomarker levels while also experiencing greater biomarker declines in the first year of ART. Changes in biomarkers to year 1 showed no significant associations with non-AIDS events. Cases, however, had significantly greater increases in all plasma biomarkers (but not cellular activation) from year 1 to the visit preceding the event.Conclusions: Inflammation increases prior to non-AIDS events in treated HIV-infected adults. These biomarker changes may reflect subclinical disease processes or other alterations in the inflammatory environment that causally contribute to disease.Clinical Trials Registration: NCT00001137. [ABSTRACT FROM AUTHOR]

Background: Monocytes and monocyte-derived macrophages promote atherosclerosis through increased inflammation and vascular remodeling. This may be especially true in chronic human immunodeficiency virus (HIV) infection.Methods: We examined 778 women (74% HIV+) in the Women's Interagency HIV Study and 503 men (65% HIV+) in the Multicenter AIDS Cohort Study who underwent repeated B-mode carotid artery ultrasound imaging in 2004-2013. We assessed baseline associations of the serum macrophage inflammation markers soluble (s)CD163, sCD14, galectin-3 (Gal-3), and Gal-3 binding protein (Gal-3BP) with carotid plaque formation (focal intima-media thickness >1.5 mm) over 7 years.Results: Marker levels were higher in HIV+ persons versus HIV- persons. Presence of focal plaque increased over time: from 8% to 15% in women, and 24% to 34% in men. After adjustment for demographic, behavioral, and cardiometabolic factors, and CRP and interleukin-6, each standard deviation increase in sCD14 was associated with increased plaque formation (risk ratio [RR] 1.24, 95% confidence interval [CI] 1.07-1.43). This pattern was consistentby sex. sCD163 was associated with plaque formation in virally suppressed HIV+ men (RR 1.52, 95% CI 1.04-2.22); Gal-3BP and Gal-3 were not associated with increased plaque.Conclusions: sCD14 and sCD163 may play important roles in atherogenesis among HIV+ persons. [ABSTRACT FROM AUTHOR]

Background: Rifaximin, a nonabsorbable antibiotic that decreases lipopolysaccharide (LPS) in cirrhotics, may decrease the elevated levels of microbial translocation, T-cell activation and inflammation in human immunodeficiency virus (HIV)-positive immune nonresponders to antiretroviral therapy (ART).Methods: HIV-positive adults receiving ART for ≥96 weeks with undetectable viremia for ≥48 weeks and CD4(+) T-cell counts <350 cells/mm(3) were randomized 2:1 to rifaximin versus no study treatment for 4 weeks. T-cell activation, LPS, and soluble CD14 were measured at baseline and at weeks 2, 4, and 8. Wilcoxon rank sum tests compared changes between arms.Results: Compared with no study treatment (n = 22), rifaximin (n = 43) use was associated with a significant difference between study arms in the change from baseline to week 4 for CD8(+)T-cell activation (median change, 0.0% with rifaximin vs +0.6% with no treatment; P = .03). This difference was driven by an increase in the no-study-treatment arm because there was no significant change within the rifaximin arm. Similarly, although there were significant differences between study arms in change from baseline to week 2 for LPS and soluble CD14, there were no significant changes within the rifaximin arm.Conclusions: In immune nonresponders to ART, rifaximin minimally affected microbial translocation and CD8(+)T-cell activation. Trial registration number. NCT01466595. [ABSTRACT FROM AUTHOR]

Abnormal levels of inflammation are associated with cardiovascular disease and mortality in human immunodeficiency virus (HIV)–infected patients. Microbial translocation, which may cause inflammation, is decreased by sevelamer in patients undergoing hemodialysis. In this single-arm study, we evaluated the effects of 8 weeks of sevelamer therapy on 36 HIV-infected subjects who were not receiving antiretroviral therapy. Sevelamer did not significantly change markers of microbial translocation, inflammation, or T-cell activation. During sevelamer treatment, however, levels of soluble tissue factor, low-density lipoprotein (LDL) cholesterol, and oxidized LDL cholesterol decreased significantly, whereas D-dimer levels increased. Thus, in this study population, sevelamer did not reduce microbial translocation but may have yielded cardiovascular benefits.Clinical Trials Registration. NCT 01543958. [ABSTRACT FROM AUTHOR]

Background: Defining the association of non-AIDS-defining events with inflammation and immune activation among human immunodeficiency virus (HIV)-infected persons with antiretroviral therapy (ART)-associated virological suppression is critical to identifying interventions to decrease the occurrence of these events.Methods: We conducted a case-control study of HIV-infected subjects who had achieved virological suppression within 1 year after ART initiation. Cases were patients who experienced non-AIDS-defining events, defined as myocardial infarction, stroke, non-AIDS-defining cancer, non-AIDS-defining serious bacterial infection, or death. Controls were matched to cases on the basis of age, sex, pre-ART CD4(+) T-cell count, and ART regimen. Peripheral blood mononuclear cells and plasma specimens obtained at the visit before ART initiation (hereafter, baseline), the visit approximately 1 year after ART initiation (hereafter, year 1), and the visit immediately preceding the non-AIDS-defining event (hereafter, pre-event) were analyzed for activated CD4(+) and CD8(+) T cells, plasma interleukin 6 (IL-6) level, soluble tumor necrosis factor receptor I (sTNFR-I) level, sTNFR-II level, soluble CD14 level, kynurenine-to-tryptophan (KT) ratio, and D-dimer level. Conditional logistic regression analysis was used to study the association between biomarkers and outcomes, with adjustment for potential confounders.Results: Higher IL-6 level, sTNFR-I level, sTNFR-II level, KT ratio, and D-dimer level at year 1 were associated with the occurrence of a non-AIDS-defining event. Significant associations were also seen between non-AIDS-defining events and values of these biomarkers in specimens obtained at baseline and the pre-event time points. Effects remained significant after control for confounders. T-cell activation was not significantly related to outcomes.Conclusions: Interventional trials to decrease the incidence of non-AIDS-defining events among HIV-infected persons with virological suppression should consider targeting the pathways represented by these soluble markers. Clinical Trials Registration. NCT00001137. [ABSTRACT FROM AUTHOR]

We examined associations of 5 plasma choline metabolites with carotid plaque among 520 HIV-infected and 217 HIV-uninfected participants (112 incident plaque cases) over 7 years. After multivariable adjustment, higher gut microbiota-related metabolite trimethylamine-N-oxide (TMAO) was associated with an increased risk of carotid plaque in HIV-infected participants (risk ratio = 1.25 per standard deviation increment; 95% confidence interval, 1.05-1.50; P = .01). TMAO was positively correlated with biomarkers of monocyte activation and inflammation (sCD14, sCD163). Further adjustment for these biomarkers attenuated the association between TMAO and carotid plaque (P = .08). Among HIV-infected individuals, plasma TMAO was associated with carotid atherosclerosis progression, partially through immune activation and inflammation. [ABSTRACT FROM AUTHOR]

Host metabolic dysregulation, especially in tryptophan metabolism, is intricately linked to COVID-19 severity and its post-acute sequelae (Long COVID). People living with HIV (PLWH) experience similar metabolic dysregulation and face an increased risk of developing Long COVID. However, whether pre-existing HIV-associated metabolic dysregulations contribute in predisposing PLWH to severe COVID-19 outcomes remains underexplored. Analyzing pre-pandemic samples from PLWH with documented post-infection outcomes, we found specific metabolic alterations, including increased tryptophan catabolism, predicting an elevated risk of severe COVID-19 and the incidence of Long COVID. These alterations warrant further investigation for their potential prognostic and mechanistic significance in determining COVID-19 complications., (© The Author(s) 2024. Published by Oxford University Press on behalf of Infectious Diseases Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Interleukin 32 (IL-32) is a potent multi-isoform proinflammatory cytokine, which is upregulated in people with HIV (PWH) and is associated with cardiovascular disease (CVD) risk. However, the impact of IL-32 isoforms on CD4 T-cell cardiotropism, a mechanism potentially contributing to heart inflammation, remains unknown. Here we show that IL-32 isoforms β and γ induce the generation of CCR4+CXCR3+ double positive (DP) memory CD4 T-cell subpopulation expressing the tyrosine kinase receptor c-Met, a phenotype associated with heart-homing of T cells. Our ex vivo studies on PWH show that the frequency of DP CD4 T cells is significantly higher in individuals with, compared to individuals without, subclinical atherosclerosis and that DP cells from antiretroviral-naive and treated individuals are highly enriched with HIV DNA. Together, these data demonstrate that IL-32 isoforms have the potential to induce heart-homing of HIV-infected CD4 T cells, which may further aggravate heart inflammation and CVD in PWH., Competing Interests: Potential conflicts of interest. All authors: No reported conflicts. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (© The Author(s) 2023. Published by Oxford University Press on behalf of Infectious Diseases Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)