Soluble CD14 is a nonspecific marker of monocyte activation

Inflammatory Biomarker Reduction With Fostemsavir Over 96 Weeks in Heavily Treatment-Experienced Adults With Multidrug-Resistant HIV-1 in the BRIGHTE Study

Background

Fostemsavir, a first-in-class attachment inhibitor that binds to the viral envelope protein gp120, is approved for heavily treatment-experienced persons with HIV-1 with limited treatment options. We explored changes in immunologic and coagulopathy parameters in the BRIGHTE study: a phase 3 trial that evaluated fostemsavir plus optimized background therapy in heavily treatment-experienced adults with multidrug-resistant HIV-1.

Methods

CD4+ T-cell count, CD4+/CD8+ ratio, soluble CD14, soluble CD163, and D-dimer levels were measured through 96 weeks in participants with 1 or 2 fully active antiretroviral agents available at screening. No formal statistical analyses were performed.

Results

Among 272 participants, increases were observed from baseline to week 96 in CD4+ T-cell count (mean increase, +205 cells/mm3) and CD4+/CD8+ ratio (mean increase, +0.24). The proportion of observed participants with a CD4+/CD8+ ratio ≥0.45 increased from 9% (25/272) at baseline to 40% (85/213) at week 96. From baseline to week 96, we also observed trends toward decreases in the following (mean [SD] change): soluble CD14, -738.2 (981.8) µg/L; soluble CD163, -138.0 (193.4) µg/L; and D-dimer, -0.099 (0.521) mg/L fibrinogen-equivalent units. Decreases in biomarkers were generally observed among subgroups by baseline disease characteristics, virologic response, and CD4+ T-cell count.

Conclusions

These data suggest that heavily treatment-experienced persons with multidrug-resistant HIV-1 treated with fostemsavir + optimized background therapy may have improvements in immune parameters, including markers of monocyte activation and coagulopathy.

Clinical Trials Registration

NCT02362503 (ClinicalTrials.gov; https://clinicaltrials.gov/study/NCT02362503).

Brain-body mechanisms contribute to sexual dimorphism in amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is the most common form of human motor neuron disease. It is characterized by the progressive degeneration of upper and lower motor neurons, leading to generalized motor weakness and, ultimately, respiratory paralysis and death within 3-5 years. The disease is shaped by genetics, age, sex and environmental stressors, but no cure or routine biomarkers exist for the disease. Male individuals have a higher propensity to develop ALS, and a different manifestation of the disease phenotype, than female individuals. However, the mechanisms underlying these sex differences remain a mystery. In this Review, we summarize the epidemiology of ALS, examine the sexually dimorphic presentation of the disease and highlight the genetic variants and molecular pathways that might contribute to sex differences in humans and animal models of ALS. We advance the idea that sexual dimorphism in ALS arises from the interactions between the CNS and peripheral organs, involving vascular, metabolic, endocrine, musculoskeletal and immune systems, which are strikingly different between male and female individuals. Finally, we review the response to treatments in ALS and discuss the potential to implement future personalized therapeutic strategies for the disease.

Menopause and Estrogen Associations With Gut Barrier, Microbial Translocation, and Immune Activation Biomarkers in Women With and Without HIV

OBJECTIVES

Estrogens may protect the gut barrier and reduce microbial translocation and immune activation, which are prevalent in HIV infection. We investigated relationships of the menopausal transition and estrogens with gut barrier, microbial translocation, and immune activation biomarkers in women with and without HIV.

DESIGN

Longitudinal and cross-sectional studies nested in the Women's Interagency HIV Study.

METHODS

Intestinal fatty acid binding protein, lipopolysaccharide binding protein, and soluble CD14 (sCD14) levels were measured in serum from 77 women (43 with HIV) before, during, and after the menopausal transition (∼6 measures per woman over ∼13 years). A separate cross-sectional analysis was conducted among 72 postmenopausal women with HIV with these biomarkers and serum estrogens.

RESULTS

Women in the longitudinal analysis were a median age of 43 years at baseline. In piecewise, linear, mixed-effects models with cutpoints 2 years before and after the final menstrual period to delineate the menopausal transition, sCD14 levels increased over time during the menopausal transition (Beta [95% CI]: 38 [12 to 64] ng/mL/yr, P = 0.004), followed by a decrease posttransition (-46 [-75 to -18], P = 0.001), with the piecewise model providing a better fit than a linear model (P = 0.0006). In stratified analyses, these results were only apparent in women with HIV. In cross-sectional analyses, among women with HIV, free estradiol inversely correlated with sCD14 levels (r = -0.26, P = 0.03). Lipopolysaccharide binding protein and intestinal fatty acid binding protein levels did not appear related to the menopausal transition and estrogen levels.

CONCLUSIONS

Women with HIV may experience heightened innate immune activation during menopause, possibly related to the depletion of estrogens.

Improved Gut Health May Be a Potential Therapeutic Approach for Managing Prediabetes: A Literature Review

Given the growing global threat and rising prevalence of type 2 diabetes mellitus (T2DM), addressing this metabolic disease is imperative. T2DM is preceded by prediabetes (PD), an intermediate hyperglycaemia that goes unnoticed for years in patients. Several studies have shown that gut microbial diversity and glucose homeostasis in PD or T2DM patients are affected. Therefore, this review aims to synthesize the existing literature to elucidate the association between high-calorie diets, intestinal permeability and their correlation with PD or T2DM. Moreover, it discusses the beneficial effects of different dietary interventions on improving gut health and glucose metabolism. The primary factor contributing to complications seen in PD or T2DM patients is the chronic consumption of high-calorie diets, which alters the gut microbial composition and increases the translocation of toxic substances from the intestinal lumen into the bloodstream. This causes an increase in inflammatory response that further impairs glucose regulation. Several dietary approaches or interventions have been implemented. However, only a few are currently in use and have shown promising results in improving beneficial microbiomes and glucose metabolism. Therefore, additional well-designed studies are still necessary to thoroughly investigate whether improving gut health using other types of dietary interventions can potentially manage or reverse PD, thereby preventing the onset of T2DM.

Effect of Sugar- and Polyphenol-Rich, Diluted Cloudy Apple Juice on the Intestinal Barrier after Moderate Endurance Exercise and in Ultra-Marathon Runners

BACKGROUND

Exercise and the consumption of sugars result in a dysfunction of the intestinal barrier (IB). Here, we determined the effect of sugar in a natural matrix on the intestinal barrier after moderate (A) and intensive endurance exercise (B).

METHOD

The IB function was determined before (pre) and after running (post), and 120 and 180 min after consuming the drink by measuring serum endotoxin concentrations (lipopolysaccharides-LPS), IL-6, CD14, and i-FABP. In study A, nonspecifically trained participants (n = 24, males and females, age 26 ± 4) ran for one hour at 80% of their individual anaerobic threshold (IAT). After finishing, the runners consumed, in a crossover setup, either 500 mL of water, diluted cloudy apple juice (test drink), or an identical drink (placebo) without the fruit juice matrix (FJM). In study B, the participants (n = 30, males and females, age 50 ± 9) completed an ultra-marathon run, were divided into groups, and consumed one of the above-mentioned drinks.

RESULTS

Study A: Exercise resulted in a significant increase in serum LPS, i-FABP, and IL-6, which decreased fast after finishing. No impact of the different drinks on LPS i-FABP, or IL-6 could be observed, but there was an impact on CD14. Study B: The ultra-marathon resulted in a strong increase in serum LPS, which decreased fast after finishing in the water and test drink groups, but not in the placebo group.

CONCLUSIONS

The consumed drinks did not affect the kinetics of IB regeneration after moderate exercise, but impacted CD14 serum concentrations, indicating possible beneficial effects of the FJM on the immune system. After an ultra-marathon, IB function regenerates very fast. The intake of sugar (placebo) seems to have had a negative impact on IB regeneration, which was diminished by the presence of the FJM.

Soluble Factors CD14, CD163, and Migration Inhibitory Factor Are Associated with Endometriosis-Related Infertility

OBJECTIVES

Myeloid cell-derived factors contribute to the immunopathology of endometriosis. Soluble CD14 (sCD14), CD163 (sCD163), and MIF serve as in vivo markers of myeloid function. However, these soluble molecules are largely unexplored in women with endometriosis-related infertility cases. We investigated three soluble markers, namely sCD14, sCD163, and MIF, in cases of infertility associated with endometriosis and correlated its level to the stage of endometriosis.

DESIGN

Eighty-seven women newly diagnosed with endometriosis or other benign gynecologic control cases linked to infertility were prospectively recruited and underwent diagnostic laparoscopy.

PARTICIPANTS

Forty-four patients with endometriosis were included in this study, comprising 19 patients with early-endometriosis (stages I and II) and 25 late-endometriosis (stages III and IV) based on the revised American Society for Reproductive Medicine (rASRM) classification. The remaining 43 patients constituted a control group with infertility due to other causes.

METHODS

The levels of sCD14, sCD163, and MIF in serum and peritoneal fluid were assessed using ELISA.

RESULTS

Endometriosis women exhibited significantly higher serum levels of sCD163 and MIF levels compared to the control group. Both sCD163 and MIF levels displayed a positive correlation with the rASRM adhesion score. Moreover, the MIF level in serum had a positive correlation with the rASRM endometriosis score. In receiver operating characteristic analysis, serum sCD163 and MIF could significantly discriminate endometriosis and non-endometriosis in infertility cases.

LIMITATIONS

Some limitations of the current study deserve to be underlined. First, the sensitive ELISA method was the sole-validated tool for detecting the markers in patient samples. Second, healthy or fertile women were not involved as the control group.

CONCLUSIONS

The elevated systemic levels of sCD163 and MIF correlated with the severity of endometriosis. These soluble molecules have a potential diagnostic capacity as a non-invasive biomarker. Furthermore, our data warrants future studies on the underlying mechanism of sCD163 and MIF in endometriosis-related infertility.

Intestinal immunological events of acute and resolved SARS-CoV-2 infection in non-human primates

SARS-CoV-2 infection has been associated with intestinal mucosal barrier damage, leading to microbial and endotoxin translocation, heightened inflammatory responses, and aggravated disease outcomes. This study aimed to investigate the immunological mechanisms associated with impaired intestinal barrier function. We conducted a comprehensive analysis of gut damage and inflammation markers and phenotypic characterization of myeloid and lymphoid populations in the ileum and colon of SARS-CoV-2-exposed macaques during both the acute and resolved infection phases. Our findings revealed a significant accumulation of terminally differentiated and activated CD4+ and CD8+ T cells, along with memory B cells, within the gastrointestinal tract up to 43 days after exposure to SARS-CoV-2. This robust infection-induced immune response was accompanied by a notable depletion of plasmacytoid dendritic cells, myeloid dendritic cells, and macrophages, particularly affecting the colon during the resolved infection phase. Additionally, we identified a population of CX3CR1Low inflammatory macrophages associated with intestinal damage during active viral replication. Elevated levels of immune activation and gut damage markers, and perturbation of macrophage homeostasis, persisted even after the resolution of the infection, suggesting potential long-term clinical sequelae. These findings enhance our understanding of gastrointestinal immune pathology following SARS-CoV-2 infection and provide valuable information for developing and testing medical countermeasures.

Accelerated Neuroimmune Dysfunction in Aged HIV-1-Infected Humanized Mice

Disordered immunity, aging, human immunodeficiency virus type one (HIV-1) infection, and responses to antiretroviral therapy are linked. However, how each factor is linked with the other(s) remains incompletely understood. It has been reported that accelerated aging, advanced HIV-1 infection, inflammation, and host genetic factors are associated with host cellular, mitochondrial, and metabolic alterations. However, the underlying mechanism remains elusive. With these questions in mind, we used chronically HIV-1-infected CD34-NSG humanized mice (hu-mice) to model older people living with HIV and uncover associations between HIV-1 infection and aging. Adult humanized mice were infected with HIV-1 at the age of 20 weeks and maintained for another 40 weeks before sacrifice. Animal brains were collected and subjected to transcriptomics, qPCR, and immunofluorescence assays to uncover immune disease-based biomarkers. CD4+ T cell decline was associated with viral level and age. Upregulated C1QA, CD163, and CXCL16 and downregulated LMNA and CLU were identified as age-associated genes tied to HIV-1 infection. Ingenuity pathway analysis affirmed links to innate immune activation, pyroptosis signaling, neuroinflammation, mitochondrial dysfunction, cellular senescence, and neuronal dysfunction. In summary, CD34-NSG humanized mice are identified as a valuable model for studying HIV-1-associated aging. Biomarkers of immune senescence and neuronal signaling are both age- and virus-associated. By exploring the underlying biological mechanisms that are linked to these biomarkers, interventions for next generation HIV-1-infected patients can be realized.

Early cellular and molecular signatures correlate with severity of West Nile virus infection

Infection with West Nile virus (WNV) drives a wide range of responses, from asymptomatic to flu-like symptoms/fever or severe cases of encephalitis and death. To identify cellular and molecular signatures distinguishing WNV severity, we employed systems profiling of peripheral blood from asymptomatic and severely ill individuals infected with WNV. We interrogated immune responses longitudinally from acute infection through convalescence employing single-cell protein and transcriptional profiling complemented with matched serum proteomics and metabolomics as well as multi-omics analysis. At the acute time point, we detected both elevation of pro-inflammatory markers in innate immune cell types and reduction of regulatory T cell activity in participants with severe infection, whereas asymptomatic donors had higher expression of genes associated with anti-inflammatory CD16+ monocytes. Therefore, we demonstrated the potential of systems immunology using multiple cell-type and cell-state-specific analyses to identify correlates of infection severity and host cellular activity contributing to an effective anti-viral response.

Autonomic Neuropathy is Associated with More Densely Interconnected Cytokine Networks in People with HIV

The autonomic nervous system (ANS) plays a complex role in the regulation of the immune system, with generally inhibitory effects via activation of β-adrenergic receptors on immune cells. We hypothesized that HIV-associated autonomic neuropathy (HIV-AN) would result in immune hyperresponsiveness which could be depicted using network analyses. Forty-two adults with well-controlled HIV underwent autonomic testing to yield the Composite Autonomic Severity Score (CASS). The observed range of CASS was 2-5, consistent with normal to moderate HIV-AN. To construct the networks, participants were divided into 4 groups based on the CASS (i.e., 2, 3, 4 or 5). Forty-four blood-based immune markers were included as nodes in all networks and the connections (i.e., edges) between pairs of nodes were determined by their bivariate Spearman's Rank Correlation Coefficient. Four centrality measures (strength, closeness, betweenness and expected influence) were calculated for each node in each network. The median value of each centrality measure across all nodes in each network was calculated as a quantitative representation of network complexity. Graphical representation of the four networks revealed greater complexity with increasing HIV-AN severity. This was confirmed by significant differences in the median value of all four centrality measures across the networks (p ≤ 0.025 for each). Among people with HIV, HIV-AN is associated with stronger and more numerous positive correlations between blood-based immune markers. Findings from this secondary analysis can be used to generate hypotheses for future studies investigating HIV-AN as a mechanism contributing to the chronic immune activation observed in HIV.

Pharmacological and Behavioral Interventions to Mitigate Premature Aging in Patients with HIV

PURPOSE OF REVIEW

We sought to review pharmacological and behavioral interventions that have been publicly presented, published, or are currently ongoing to prevent or mitigate the effect of premature HIV-associated comorbidities.

RECENT FINDINGS

Multiple studies have been conducted in hopes of finding an effective intervention. While the choice of antiretroviral regimen influences recovery of immune function, several drugs used as adjunct treatments have proven effective to mitigate premature aging. Additionally, few behavioral interventions have exhibited some efficacy. Statins, angiotensin-receptor blockers, and anti-hyperglycemic agents as well as optimal adherence, exercise, and intermittent fasting among others have had beneficial impact on markers of immune activation and levels of inflammatory biomarkers. However, several investigations had inconclusive outcomes so further studies with larger sample sizes are warranted.

Identification of drug candidates targeting monocyte reprogramming in people living with HIV

Introduction

People living with HIV (PLHIV) are characterized by functional reprogramming of innate immune cells even after long-term antiretroviral therapy (ART). In order to assess technical feasibility of omics technologies for application to larger cohorts, we compared multiple omics data layers.

Methods

Bulk and single-cell transcriptomics, flow cytometry, proteomics, chromatin landscape analysis by ATAC-seq as well as ex vivo drug stimulation were performed in a small number of blood samples derived from PLHIV and healthy controls from the 200-HIV cohort study.

Results

Single-cell RNA-seq analysis revealed that most immune cells in peripheral blood of PLHIV are altered in their transcriptomes and that a specific functional monocyte state previously described in acute HIV infection is still existing in PLHIV while other monocyte cell states are only occurring acute infection. Further, a reverse transcriptome approach on a rather small number of PLHIV was sufficient to identify drug candidates for reversing the transcriptional phenotype of monocytes in PLHIV.

Discussion

These scientific findings and technological advancements for clinical application of single-cell transcriptomics form the basis for the larger 2000-HIV multicenter cohort study on PLHIV, for which a combination of bulk and single-cell transcriptomics will be included as the leading technology to determine disease endotypes in PLHIV and to predict disease trajectories and outcomes.

Investigating the Association Between Diet-Induced "Leaky Gut" and the Development of Prediabetes

INTRODUCTION

Chronic consumption of a high-calorie diet compromises the gut microbiota and the integrity of the intestinal wall, which causes translocation of bacterial lipopolysaccharides (LPS) into the blood. This elicits the secretion of pro-inflammatory cytokines, resulting in inflammation. However, how a high-fat high carbohydrate diet affects intestinal permeability and its possible role in the development of prediabetes have not been investigated. This study investigated the effects of HFHC diet-induced prediabetes on gut microbiota and intestinal permeability in male Sprague Dawley rats.

METHODS

The animals were randomly assigned into the non-prediabetic (NPD) and diet-induced prediabetic (PD) groups (n=6) for 20 weeks. Then, the fecal samples were analyzed to measure the gut microbiota level of Firmicutes, Bacteroidetes, and Proteobacteria in both animal groups. Blood glucose, plasma insulin, serum zonulin, plasma LPS, soluble CD14, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), C-reactive protein (CRP), and intestinal fatty-acid binding protein (IFABP) concentrations were measured.

RESULTS

The PD group had a reduction in the Firmicutes and an increase in Bacteroidetes and Proteobacteria levels compared to those in the NPD group. Blood glucose, insulin concentration, serum zonulin, and plasma sCD14 concentrations in the PD group increased significantly, while plasma LPS concentrations were similar to the NPD group. Concentrations of plasma TNF-α, IL-6, CRP, and IFABP, an intracellular protein expressed in the intestine, increased in PD compared to the NPD group.

CONCLUSIONS

the study results cumulatively suggest that chronic consumption of the HFHC diet may be associated with the dysregulation of gut microbiota, leading to increased intestinal permeability.

Increased Peripheral Inflammation Is Associated With Structural Brain Changes and Reduced Blood Flow in People With Virologically Controlled HIV

BACKGROUND

While antiretroviral therapy (ART) has improved outcomes for people with HIV (PWH), brain dysfunction is still evident. Immune activation and inflammation remain elevated in PWH receiving ART, thereby contributing to morbidity and mortality. Previous studies demonstrated reduced functional and structural changes in PWH; however, underlying mechanisms remain elusive.

METHODS

Our cohort consisted of PWH with ART adherence and viral suppression ( < 50 copies/mL; N = 173). Measurements included immune cell markers of overall immune health (CD4/CD8 T-cell ratio) and myeloid inflammation (CD16+ monocytes), plasma markers of inflammatory status (soluble CD163 and CD14), and structural and functional neuroimaging (volume and cerebral blood flow [CBF], respectively).

RESULTS

Decreased CD4/CD8 ratios correlated with reduced brain volume, and higher levels of inflammatory CD16+ monocytes were associated with reduced brain volume in total cortex and gray matter. An increase in plasma soluble CD14-a marker of acute peripheral inflammation attributed to circulating microbial products-was associated with reduced CBF within the frontal, parietal, temporal, and occipital cortices and total gray matter.

CONCLUSIONS

CD4/CD8 ratio and number of CD16+ monocytes, which are chronic immune cell markers, are associated with volumetric loss in the brain. Additionally, this study shows a potential new association between plasma soluble CD14 and CBF.

Stimulant use, HIV, and immune dysregulation among sexual minority men

BACKGROUND

Sexual minority men (SMM) report high rates of stimulant use (e.g., crystal methamphetamine, cocaine) and HIV infection. Stimulant use contributes to immune dysfunction, which enhances risk for HIV acquisition and pathogenesis. Research is needed to examine the independent and interactive relationships of stimulant use and HIV infection with systemic immune dysregulation among SMM, especially during the COVID-19 pandemic.

METHODS

From 2020-2022, 75 SMM in Miami, Florida with and without HIV completed an online survey and provided biospecimens to assess HIV status and viral load (VL), recent stimulant use, and soluble markers of immune activation and inflammation in plasma, including soluble CD14 (sCD14) and elevated high-sensitivity C-reactive protein (hs-CRP > 1.0mg/L). Sociodemographics and prior SARS-CoV-2 infection were compared across HIV status/stimulant use groups. Moderation models examined the independent and interactive associations of stimulant use and HIV status with sCD14 and elevated hs-CRP.

RESULTS

Thirty participants were persons living with HIV (PWH) (50% with stimulant use), and 45 were HIV-negative (44% with stimulant use). SARS-CoV-2 infection was not associated with stimulant use/HIV groups or immune outcomes. HIV-negative SMM without stimulant use had lower sCD14 compared to other SMM, as well as lower odds of elevated hs-CRP compared to PWH who used stimulants. Stimulant use showed independent associations with immune dysregulation that persisted after controlling for HIV status and VL, whereas HIV status was only independently associated with elevated hs-CRP in one model not controlling for VL.

CONCLUSIONS

Among SMM, stimulant use was independently associated with elevated immune activation and inflammation.

Combined effects of loneliness and inflammation on depression in people with HIV

OBJECTIVE

Loneliness is prevalent in people with HIV (PWH) and associated with adverse health-related consequences, including depression. Chronic inflammation has been linked to depression in PWH, though its association with loneliness is less well established. Simultaneous examination of inflammation, loneliness and depression is needed to clarify these relationships. This study investigated the relationship between loneliness and inflammation, and the effects of loneliness and inflammation on depression in PWH.

METHODS

82 PWH who were on suppressive ART (mean age [SD] = 53.2 [9.0]) completed the UCLA Loneliness Scale-Version 3 and the Center for Epidemiologic Studies Depression Scale as part of a comprehensive evaluation. Biomarkers of systemic inflammation (CRP, IL-6, CCL2/MCP-1, sCD14) and coagulation (D-dimer) were measured in blood using commercial immunoassays.

RESULTS

Multivariable linear regression analyses revealed that higher D-dimer, CCL2/MCP-1, and sCD14 were significant predictors of loneliness (ps < .05) while accounting for relevant covariates. Stepwise multiple linear regression models that included loneliness, biomarkers, and their interactions as predictors of depressive symptoms revealed significant main effects of loneliness and CCL2/MCP-1 levels (ps < .05), and a significant loneliness by D-dimer interaction (p < .05) whereby higher D-dimer was associated with increased depressive symptoms only at higher levels of loneliness.

CONCLUSIONS

Increased coagulation activity is associated with loneliness, and in the context of loneliness, may increase risk for depression. Increased inflammation was associated with depression suggesting potentially dissociable underlying biological processes. To the extent that these processes are modifiable, such findings could have important implications in the treatment of loneliness and depression in PWH.

Fetal and neonatal alloimmune thrombocytopenia: No evidence of systemic inflammation as a modulator of disease severity. Could placental inflammation be key?

In fetal/neonatal alloimmune thrombocytopenia (FNAIT), maternal alloantibodies against paternal human platelet antigens (HPA) cross the placenta and lead to platelet destruction. The extent of thrombocytopenia varies among neonates, and inflammation may constitute an important trigger. A set of stable inflammatory markers was measured in serum samples from neonates with low platelet counts, of which n = 50 were diagnosed with FNAIT due to anti-HPA-1a antibodies and n = 50 were thrombocytopenic without detectable maternal HPA antibodies. Concentrations of C-reactive protein, soluble CD14, procalcitonin, and sFlt-1 did not differ between the two cohorts. There was no correlation between C-reactive protein or soluble CD14 and the platelet count, but a negative correlation between procalcitonin concentrations and the neonatal platelet count in both cohorts. sFlt-1 concentration and the platelet count were correlated in FNAIT cases exclusively. None of the inflammatory markers was statistically different between cases with and without intracranial haemorrhage. We were unable to identify systemic inflammation as a relevant factor for thrombocytopenia in FNAIT. The antiangiogenic enzyme sFlt-1, released by the placenta, did correlate with the platelet count in FNAIT cases. Our findings may give rise to the hypothesis that placental inflammation rather than systemic inflammation modulates disease severity in FNAIT.

Preliminary Study of sCD14 and sCD163 as Predictors of Disease Severity and ICU Admission in COVID-19: Relation to Hematological Parameters, Blood Morphological Changes and Inflammatory Biomarkers

Background and Objectives

Research supports the role of monocyte/macrophage activation in COVID-19 immunopathology. This study aimed to evaluate sCD14 and sCD163 - the monocyte activation markers - and to investigate their relation to hematological parameters and blood morphology in COVID-19 infection.

Methods

This is a case-control study that included 70 COVID-19 patients. Patients were subdivided into two groups: 23 severely diseased ICU-admitted patients and another group of 47 non-ICU-admitted patients. sCD163 and sCD14 levels were determined using ELISA.

Results

sCD163 and sCD14 showed significantly higher levels in sera of patients compared to the control group, with significantly higher levels of sCD163 in ICU-admitted patients than non-ICU admitted patients. Receiver operating characteristic curve analysis demonstrated the usefulness of sCD163 with a cut-off value of 734 ng/mL as a potential marker to discriminate between ICU and non-ICU admitted COVID-19 patients (sensitivity of 81.16%; specificity of 96.67% and positive predictive value of 98% with area under the curve of 0.930). sCD163 levels showed a positive correlation with total white blood cells, absolute neutrophilic count, Neutrophil/Lymphocyte ratio, and a negative correlation with platelet count. sCD14 levels positively correlated with D-dimer values associated with a shift to the left and neutrophilic toxic granulations in blood morphology.

Conclusion

High sCD163 and sCD14 levels, hematological parameters, and blood morphology reflect monocyte activation in COVID-19 infection. sCD163 is a potential marker of disease severity. These findings support further study of therapeutics targeting macrophage activity in COVID-19 patients with high sCD163 levels.

Depression and HIV: a scoping review in search of neuroimmune biomarkers

People with HIV are at increased risk for depression, though the neurobiological mechanisms underlying this are unclear. In the last decade, there has been a substantial rise in interest in the contribution of (neuro)inflammation to depression, coupled with rapid advancements in the resolution and sensitivity of biomarker assays such as Luminex, single molecular array and newly developed positron emission tomography radioligands. Numerous pre-clinical and clinical studies have recently leveraged these next-generation immunoassays to identify biomarkers that may be associated with HIV and depression (separately), though few studies have explored these biomarkers in co-occurring HIV and depression. Using a systematic search, we detected 33 publications involving a cumulative N = 10 590 participants which tested for associations between depressive symptoms and 55 biomarkers of inflammation and related processes in participants living with HIV. Formal meta-analyses were not possible as statistical reporting in the field was highly variable; future studies must fully report test statistics and effect size estimates. The majority of included studies were carried out in the United States, with samples that were primarily older and primarily men. Substantial further work is necessary to diversify the geographical, age, and sex distribution of samples in the field. This review finds that alterations in concentrations of certain biomarkers of neuroinflammation (interleukin-6, tumour necrosis factor-α, neopterin) may influence the association between HIV and depression. Equally, the chemokines monocyte chemoattractant protein-1 (MCP-1) and interleukin-8 (IL-8) or the metabolic index kynurenine:tryptophan (Kyn:Trp), which have been the focus of several studies, do not appear to be associated with depressive symptoms amongst people living with HIV, as all (MCP-1) or most (IL-8 and Kyn:Trp) available studies of these biomarkers reported non-significant associations. We propose a biomarker-driven hypothesis of the neuroimmunometabolic mechanisms that may precipitate the increased risk of depression among people with HIV. Chronically activated microglia, which trigger key neuroinflammatory cascades shown to be upregulated in people with HIV, may be the central link connecting HIV infection in the central nervous system with depressive symptoms. Findings from this review may inform research design in future studies of HIV-associated depression and enable concerted efforts towards biomarker discovery.

Endotoxemia Associated with Liver Disease Correlates with Systemic Inflammation and T Cell Exhaustion in Hepatitis C Virus Infection

Both acute and chronic hepatitis C virus (HCV) infections are characterized by inflammation. HCV and reduced liver blood filtration contribute to inflammation; however, the mechanisms of systemic immune activation and dysfunction as a result of HCV infection are not clear. We measured circulating inflammatory mediators (IL-6, IP10, sCD163, sCD14), indices of endotoxemia (EndoCab, LBP, FABP), and T cell markers of exhaustion and senescence (PD-1, TIGIT, CD57, KLRG-1) in HCV-infected participants, and followed a small cohort after direct-acting anti-viral therapy. IL-6, IP10, Endocab, LBP, and FABP were elevated in HCV participants, as were T cell co-expression of exhaustion and senescence markers. We found positive associations between IL-6, IP10, EndoCab, LBP, and co-expression of T cell markers of exhaustion and senescence. We also found numerous associations between reduced liver function, as measured by plasma albumin levels, and T cell exhaustion/senescence, inflammation, and endotoxemia. We found positive associations between liver stiffness (TE score) and plasma levels of IL-6, IP10, and LBP. Lastly, plasma IP10 and the proportion of CD8 T cells co-expressing PD-1 and CD57 decreased after initiation of direct-acting anti-viral therapy. Although associations do not prove causality, our results support the model that translocation of microbial products, resulting from decreased liver blood filtration, during HCV infection drives chronic inflammation that results in T cell exhaustion/senescence and contributes to systemic immune dysfunction.

Recent advances in poor HIV immune reconstitution: what will the future look like?

Combination antiretroviral therapy has demonstrated proved effectiveness in suppressing viral replication and significantly recovering CD4+ T cell count in HIV type-1 (HIV-1)-infected patients, contributing to a dramatic reduction in AIDS morbidity and mortality. However, the factors affecting immune reconstitution are extremely complex. Demographic factors, co-infection, baseline CD4 cell level, abnormal immune activation, and cytokine dysregulation may all affect immune reconstitution. According to report, 10-40% of HIV-1-infected patients fail to restore the normalization of CD4+ T cell count and function. They are referred to as immunological non-responders (INRs) who fail to achieve complete immune reconstitution and have a higher mortality rate and higher risk of developing other non-AIDS diseases compared with those who achieve complete immune reconstitution. Heretofore, the mechanisms underlying incomplete immune reconstitution in HIV remain elusive, and INRs are not effectively treated or mitigated. This review discusses the recent progress of mechanisms and factors responsible for incomplete immune reconstitution in AIDS and summarizes the corresponding therapeutic strategies according to different mechanisms to improve the individual therapy.

Cervical and systemic innate immunity predictors of HIV risk linked to genital herpes acquisition and time from HSV-2 seroconversion

OBJECTIVES

To examine innate immunity predictors of HIV-1 acquisition as biomarkers of HSV-2 risk and biological basis for epidemiologically established HIV-1 predisposition in HSV-2 infected women.

METHODS

We analysed longitudinal samples from HIV-1 negative visits of 1019 women before and after HSV-2 acquisition. We measured cervical and serum biomarkers of inflammation and immune activation previously linked to HIV-1 risk. Protein levels were Box-Cox transformed and ORs for HSV-2 acquisition were calculated based on top quartile or below/above median levels for all HSV-2 negative visits. Bivariate analysis determined the likelihood of HSV-2 acquisition by biomarker levels preceding infection. Linear mixed-effects models evaluated if biomarkers differed by HSV-2 status defined as negative, incident or established infections with an established infection cut-off starting at 6 months.

RESULTS

In the cervical compartment, two biomarkers of HIV-1 risk (low SLPI and high BD-2) also predicted HSV-2 acquisition. In addition, HSV-2 acquisition was associated with IL-1β, IL-6, IL-8, MIP-3α, ICAM-1 and VEGF when below median levels. Systemic immunity predictors of HSV-2 acquisition were high sCD14 and IL-6, with highest odds when concomitantly increased (OR=2.23, 1.49-3.35). Concomitant systemic and mucosal predictors of HSV-2 acquisition risk included (1) serum top quartile sCD14 with cervical low SLPI, VEGF and ICAM-1, or high BD-2; (2) serum high IL-6 with cervical low VEGF and ICAM-1, SLPI, IL-1β and IL-6; and (3) serum low C reactive protein with cervical high BD-2 (the only combination also predictive of HIV-1 acquisition). Most cervical biomarkers were decreased after HSV-2 acquisition compared with the HSV-2 negative visits, with incident infections associated with a larger number of suppressed cervical biomarkers and lower serum IL-6 levels compared with established infections.

CONCLUSIONS

A combination of systemic immunoinflammatory and cervical immunosuppressed states predicts HSV-2 acquisition. A persistently suppressed innate immunity during incident HSV-2 infection may add to the increased HIV-1 susceptibility.

2-Hydroxypropyl-β-Cyclodextrin Treatment Induces Modest Immune Activation in Healthy Rhesus Macaques

Experimental simian immunodeficiency virus (SIV) infection of Asian macaques is an excellent model for HIV disease progression and therapeutic development. Recent coformulations of nucleoside analogs and an integrase inhibitor have been used for parenteral antiretroviral (ARV) administration in SIV-infected macaques, successfully resulting in undetectable plasma SIV RNA. In a cohort of SIVmac239-infected macaques, we recently observed that administration of coformulated ARVs resulted in an unexpected increase in plasma levels of soluble CD14 (sCD14), associated with stimulation of myeloid cells. We hypothesized that the coformulation solubilizing agent Kleptose (2-hydroxypropyl-β-cyclodextrin [HPβCD]) may induce inflammation with myeloid cell activation and the release of sCD14. Herein, we stimulated peripheral blood mononuclear cells (PBMCs) from healthy macaques with HPβCD from different commercial sources and evaluated inflammatory cytokine production in vitro. Treatment of PBMCs resulted in increased sCD14 release and myeloid cell interleukin-1β (IL-1β) production-with stimulation varying significantly by HPβCD source-and destabilized lymphocyte CCR5 surface expression. We further treated healthy macaques with Kleptose alone. In vivo, we observed modestly increased myeloid cell activation in response to Kleptose treatment without significant perturbation of the immunological transcriptome or epigenome. Our results demonstrate a need for vehicle-only controls and highlight immunological perturbations that can occur when using HPβCD in pharmaceutical coformulations. IMPORTANCE SIV infection of nonhuman primates is the principal model system for assessing HIV disease progression and therapeutic development. HPβCD has recently been incorporated as a solubilizing agent in coformulations of ARVs in SIV-infected nonhuman primates. Although HPβCD has historically been considered inert, recent findings suggest that HPβCD may contribute to inflammation. Herein, we investigate the contribution of HPβCD to healthy macaque inflammation in vitro and in vivo. We observe that HPβCD causes an induction of sCD14 and IL-1β from myeloid cells in vitro and demonstrate that HPβCD stimulatory capacity varies by commercial source. In vivo, we observe modest myeloid cell activation in blood and bronchoalveolar lavage specimens absent systemic immune activation. From our findings, it is unclear whether HPβCD stimulation may improve or diminish immune reconstitution in ARV-treated lentiviral infections. Our results demonstrate a need for vehicle-only controls and highlight immunological perturbations that can occur when using HPβCD in pharmaceutical coformulations.

The Potential Role of Gut Bacteriome Dysbiosis as a Leading Cause of Periprosthetic Infection: A Comprehensive Literature Review

(1) Background: Periprosthetic joint infections (PJIs) represent a small yet important risk when undertaking a joint arthroplasty; they occur in approximately 1-2% of treatments. These infections create a medical and financial burden for patients and healthcare systems. Despite the introduction of recognized best clinical practices during arthroplasty operations, it is not yet possible to further reduce the risk of infection after surgery. The purpose of this review is to raise awareness of the potential role of gut dysbiosis in the development of PJIs and to highlight the potential of the gut bacteriome as a possible target for preventing them. (2) Methods: We compiled all the available data from five databases, examining the effects of gut dysbiosis in human and murine studies, following PRISMA guidelines, for a total of five reviewed studies. (3) Results: One human and one murine study found the Trojan horse theory applicable. Additionally, inflammatory bowel diseases, gut permeability, and oral antibiotic ingestion all appeared to play a role in promoting gut dysbiosis to cause PJIs, according to the other three studies. (4) Conclusions: Gut dysbiosis is linked to an increased risk of PJI.

sCD14 and Intestinal Fatty Acid Binding Protein Are Elevated in the Serum of Patients With Idiopathic Anaphylaxis

BACKGROUND

Intestinal epithelial integrity compromise has been identified in gastrointestinal (GI), atopic, and autoimmune diseases.

OBJECTIVE

Episodes of idiopathic anaphylaxis (IA) are often accompanied by GI manifestations. We, therefore, sought to determine whether surrogate markers of GI permeability were aberrant in this patient population.

METHODS

Serum concentrations of zonulin, intestinal fatty acid binding protein (I-FABP), and soluble CD14 (sCD14) measured in 54 patients with IA were compared with concentrations in healthy controls (HCs); and correlated with clinical and laboratory parameters.

RESULTS

The I-FABP was elevated in sera of patients with IA compared with HCs (median 1,378.0 pg/mL vs 479.0 pg/mL, respectively; P < .001). The sCD14 was also elevated compared with HCs (median 2,017.0 ng/mL and 1,189.0 ng/mL, respectively; P < .001), whereas zonulin was comparable between patients with IA and HCs (median 49.6 ng/mL vs 52.4 ng/mL, respectively; P = .40). The I-FABP was elevated in patients with IA who experienced vomiting and/or diarrhea compared with patients with IA who did not (P = .0091).

CONCLUSIONS

The I-FABP and sCD14 are elevated in the serum of patients with IA. Elevations in these biomarkers of IA provides evidence that increased GI permeability, as is observed in other allergic conditions such as food allergy, is a common finding in those with IA and offers possible insight into the pathogenesis of this disease.

Biomarkers of gut barrier dysfunction and risk of hepatocellular carcinoma in the REVEAL-HBV and REVEAL-HCV cohort studies

Gut barrier dysfunction can result in the liver being exposed to an elevated level of gut-derived bacterial products via portal circulation. Growing evidence suggests that systemic exposure to these bacterial products promotes liver diseases including hepatitis, cirrhosis, and hepatocellular carcinoma (HCC). However, prospective studies have not examined the association between biomarkers of gut barrier dysfunction and HCC risk in a population of hepatitis B or C viral (HBV/HCV) carriers. We investigated whether prediagnostic, circulating biomarkers of gut barrier dysfunction were associated with HCC risk, using the Risk Evaluation of Viral Load Elevation and Associated Liver Disease/Cancer (REVEAL)-HBV and REVEAL-HCV cohorts from Taiwan. REVEAL-HBV included 185 cases and 161 matched controls, and REVEAL-HCV 96 cases and 96 matched controls. The biomarkers quantitated were immunoglobulin A (IgA), IgG, and IgM against lipopolysaccharide (LPS) and flagellin, soluble CD14 (an LPS coreceptor), and LPS-binding protein (LBP). Odds ratios (ORs) and 95% confidence intervals (CIs) for associations between biomarker levels and HCC were calculated using multivariable-adjusted logistic regression. A doubling of the circulating levels of antiflagellin IgA or LBP was associated with a 76% to 93% increased risk of HBV-related HCC (OR per one unit change in log2 antiflagellin IgA = 1.76, 95% CI: 1.06-2.93; OR for LBP = 1.93, 95% CI: 1.10-3.38). None of the other markers were associated with an increased risk of HBV-related or HCV-related HCC. Results were similar when cases diagnosed in the first 5 years of follow-up were excluded. Our findings contribute to understanding the interplay of gut barrier dysfunction and primary liver cancer etiology.

Assessment of interleukin-10 promoter variant (-1082A/G) and cytokine production in patients with hemolytic uremic syndrome

Introduction

Hemolytic uremic syndrome (HUS) is a condition that results in acute kidney failure mainly in children, which is caused by Shiga toxin-producing Escherichia coli and inflammatory response. Although anti-inflammatory mechanisms are triggered, studies on the implication in HUS are scarce. Interleukin-10 (IL-10) regulates inflammation in vivo, and the interindividual differences in its expression are related to genetic variants. Notably, the single nucleotide polymorphism (SNP) rs1800896 -1082 (A/G), located in the IL-10 promoter, regulates cytokine expression.

Methods

Plasma and peripheral blood mononuclear cells (PBMC) were collected from healthy children and HUS patients exhibiting hemolytic anemia, thrombocytopenia, and kidney damage. Monocytes identified as CD14⁺ cells were analyzed within PBMC by flow cytometry. IL-10 levels were quantified by ELISA, and SNP -1082 (A/G) was analyzed by allele-specific PCR.

Results

Circulating IL-10 levels were increased in HUS patients, but PBMC from these patients exhibited a lower capacity to secrete this cytokine compared with those from healthy children. Interestingly, there was a negative association between the circulating levels of IL-10 and inflammatory cytokine IL-8. We observed that circulating IL-10 levels were threefold higher in HUS patients with -1082G allele in comparison to AA genotype. Moreover, there was relative enrichment of GG/AG genotypes in HUS patients with severe kidney failure.

Discussion

Our results suggest a possible contribution of SNP -1082 (A/G) to the severity of kidney failure in HUS patients that should be further evaluated in a larger cohort.

Characterization of soluble TLR2 and CD14 levels during acute dengue virus infection

Dengue virus infection results in a broad spectrum of diseases ranging from mild dengue fever (DF) to severe dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Hitherto, there is no consensus biomarker for the prediction of severe dengue disease in patients. Yet, early identification of patients who progress to severe dengue is pivotal for better clinical management. We have recently reported that an increased frequency of classical (CD14 ⁺⁺CD16^-) monocytes with sustained high TLR2 expression in acutely infected dengue patients correlates with severe dengue development. Here, we hypothesized that the relatively lower TLR2 and CD14 expression in mild dengue patients is due to the shedding of their soluble forms (sTLR2 and sCD14) and that these could be used as indicators of disease progression. Therefore, using commercial sandwich ELISAs, we evaluated the release of sTLR2 and sCD14 by peripheral blood mononuclear cells (PBMCs) in response to in vitro dengue virus (DENV) infection and assessed their levels in acute-phase plasma of 109 dengue patients. We show that while both sTLR2 and sCD14 are released by PBMCs in response to DENV infection in vitro, their co-circulation in an acute phase of the disease is not always apparent. In fact, sTLR2 was found only in 20% of patients irrespective of disease status. In contrast, sCD14 levels were detected in all patients and were significantly elevated in DF patients when compared to DHF patients and age-matched healthy donors. Altogether, our results suggest that sCD14 may help in identifying patients at risk of severe dengue at hospital admittance.

Enhanced Mouse Susceptibility to Endotoxin Shock after Plasmodium yoelii Infection Is Correlated with Increased Serum Levels of Lipopolysaccharide Soluble Receptors

Sepsis is a common disease in sub-Saharan Africa and Asia, where malaria is also prevalent. To determine whether Plasmodium infection might enhance susceptibility to endotoxin shock, we used a mouse model of lipopolysaccharide (LPS) administration. Our results indicated that Plasmodium yoelii infection in mice strongly enhanced the susceptibility of the host to develop endotoxin shock. This increased susceptibility to endotoxin shock was correlated with a synergistic effect of Plasmodium and LPS on the secretion of Tumor Necrosis Factor (TNF). TNF contributed mostly to lethality after the dual challenge since neutralization with an anti-TNF antibody provided protection from death. Plasmodium infection also induced an enhancement of the serum levels of LPS soluble ligands, sCD14 and Lipopolysaccharide Binding Protein. In this regard, our data confirm that Plasmodium infection can profoundly modify responses to secondary bacteria challenges, resulting in dysregulated cytokine expression and pathological effects. If confirmed in humans, LPS soluble receptors might serve as markers of susceptibility to septic shock.

Autonomic Neuropathy is Associated with More Densely Interconnected Cytokine Networks in People with HIV

Introduction

The autonomic nervous system (ANS) plays a complex role in the regulation of the immune system, with generally inhibitory effects via activation of β-adrenergic receptors on immune cells. We hypothesized that HIV-associated autonomic neuropathy (HIV-AN) would result in immune hyperresponsiveness which could be depicted using network analyses.

Methods

Forty-two adults with well-controlled HIV underwent autonomic testing to yield the Composite Autonomic Severity Score (CASS). The observed range of CASS was 2-5, consistent with normal to moderate HIV-AN. To construct the networks, participants were divided into 4 groups based on the CASS (i.e., 2, 3, 4 or 5). Forty-four blood-based immune markers were included as nodes in all networks and the connections (i.e., edges) between pairs of nodes were determined by their bivariate Spearman's Rank Correlation Coefficient. Four centrality measures (strength, closeness, betweenness and expected influence) were calculated for each node in each network. The median value of each centrality measure across all nodes in each network was calculated as a quantitative representation of network complexity.

Results

Graphical representation of the four networks revealed greater complexity with increasing HIV-AN severity. This was confirmed by significant differences in the median value of all four centrality measures across the networks (p≤0.025 for each).

Conclusion

Among people with HIV, HIV-AN is associated with stronger and more numerous positive correlations between blood-based immune markers. Findings from this secondary analysis can be used to generate hypotheses for future studies investigating HIV-AN as a mechanism contributing to the chronic immune activation observed in HIV.

Sex modulates the association between inflammation and coronary atherosclerosis among older Ugandan adults with and without HIV

OBJECTIVE

Inflammation is key in the pathogenesis of atherosclerotic coronary artery disease (CAD). Distinct sex-specific inflammatory mechanisms may contribute to CAD in sub-Saharan Africa (SSA), where environmental and biological determinants of systemic inflammation may differ from those in high-income settings.

APPROACH AND RESULTS

We investigated sex differences in inflammatory markers and CAD in a 2-year prospective cohort of Ugandan adults enriched for cardiometabolic risk factors (RFs) and HIV. Seven plasma biomarkers were quantified at the baseline visit among 125 females and 75 males (50% with HIV) at least 45 years old at enrollment with one or more major cardiovascular RF. In year 2, coronary CT angiography (CCTA) was performed in 82 females and 50 males returning for follow-up (52% with HIV). In sex-specific models adjusted for cardiovascular RFs and HIV, tumor necrosis factor-alpha (TNF-α) RII and sCD163 predicted subsequent CAD in females, while only fibrinogen was predictive in males ( P  < 0.05). Interleukin-6 (IL-6) and sCD14 were inversely associated with CAD in males ( P  < 0.05). Sex modified the associations of TNF-α RII, sCD14, and sCD163 with CAD ( P  < 0.05 for interaction). In multivariable multiple imputation models applied to missing year 2 CCTA data to test associations between serum biomarkers in the baseline cohort ( n  = 200) and subsequent CAD, higher sCD163 was predictive in females only ( P  < 0.05).

CONCLUSIONS

The positive link between inflammation and subclinical CAD was stronger among females than males in Uganda. Mechanisms by which sex modulates the relationship between inflammation and CAD should be further investigated in SSA.

Unique Profile of Inflammation and Immune Activation in Pregnant People With HIV in the United States

BACKGROUND

Little is known about inflammation/immune activation during pregnancy in people with HIV (PWH) and growth in their children who are HIV-exposed and uninfected (CHEU).

METHODS

Using data from the Pediatric HIV/AIDS Cohort Study and an HIV-seronegative comparison group, we assessed associations of (1) HIV status, mode of HIV acquisition (perinatally vs nonperinatally acquired), and type of antiretroviral therapy (ART) with inflammation/immune activation in pregnancy; and (2) inflammation/immune activation in pregnancy with growth of CHEU at 12 months. Interleukin 6 (IL-6), high-sensitivity C-reactive protein (hs-CRP), soluble(s) TNF-α receptor 1 and 2 (sTNFR1, sTNFR2), sCD14, and sCD163 were measured between 13 and 27 weeks' gestation. Linear regression models were fit to estimate differences between groups for each log-transformed biomarker, adjusted for confounders.

RESULTS

Pregnant PWH (188 total, 39 perinatally acquired, 149 nonperinatally acquired) and 76 HIV-seronegative persons were included. PWH had higher IL-6, sTNFR1, sCD14, and sCD163 and lower sTNFR2 compared to HIV-seronegative persons in adjusted models. Among PWH, sCD163 was higher in those with perinatally versus nonperinatally acquired HIV and on PI-based versus INSTI-based ART. Higher maternal concentrations of IL-6, sTNFR2, and hs-CRP were associated with poorer growth at 12 months.

CONCLUSIONS

Maternal HIV status is associated with a distinct profile of inflammation/immune activation during pregnancy, which may influence child growth.

The significance of CD14 in clear cell renal cell carcinoma progression and survival prognosis

Purpose: CD14-positive tumour and immune cells have been implicated in cancer progression. This study evaluated the prognostic significance of CD14 immunostaining in clear cell renal cell carcinoma (ccRCC) compared to the adjacent non-cancer kidney, and serum soluble CD14 (sCD14) levels in patients versus controls.Methods: Immunohistochemistry was performed for CD14 on ccRCC and the corresponding adjacent non-cancer kidney tissue from 88 patients. Staining intensity was determined using Aperio ImageScope morphometry. Serum sCD14 was evaluated for 39 ccRCC patients and 38 non-cancer controls using ELISA. CD14 levels were compared with tumour characteristics and survival status.Results: CD14 overall and nuclear immunostaining was higher in ccRCC compared to the adjacent non-cancer kidney tissue. CD14 nuclear immunostaining in the adjacent non-cancer kidney was significantly associated with advanced stage and adverse RCC survival prognosis. Serum sCD14 concentration was elevated in ccRCC patients compared to non-cancer controls and was also significantly associated with tumour stage and worse survival prognosis. Higher CD14 expression, in particular CD14 positive immune cell infiltrates found in the adjacent non-RCC kidney tissue, were associated with tumour progression and poorer prognosis.Conclusion: The levels of CD14 in non-RCC adjacent kidney and serum could be potential prognostic indicators.

Cardiovascular Disease and Thrombosis in HIV Infection

HIV infection has transitioned from an acute, fatal disease to a chronic one managed by antiretroviral therapy. Thus, the aging population of people living with HIV (PLWH) continues to expand. HIV infection results in a dysregulated immune system, wherein CD4+ T cells are depleted, particularly in the gastrointestinal tract, disrupting the gut epithelial barrier. Long-term HIV infection is associated with chronic inflammation through potentially direct mechanisms caused by viral replication or exposure to viral proteins and indirect mechanisms resulting from increased translocation of microbial products from the intestine or exposure to antiretroviral therapy. Chronic inflammation (as marked by IL [interleukin]-6 and CRP [C-reactive protein]) in PLWH promotes endothelial cell dysfunction and atherosclerosis. PLWH show significantly increased rates of cardiovascular disease, such as myocardial infarction (risk ratio, 1.79 [95% CI, 1.54-2.08]) and stroke (risk ratio, 2.56 [95% CI, 1.43-4.61]). In addition, PLWH have increased levels of the coagulation biomarker D-dimer and have a two to ten-fold increased risk of venous thromboembolism compared with the general population. Several small clinical trials analyzed the effect of different antithrombotic agents on platelet activation, coagulation, inflammation, and immune cell activation. Although some markers for coagulation were reduced, most agents failed to reduce inflammatory markers in PLWH. More studies are needed to understand the underlying mechanisms driving inflammation in PLWH to create better therapies for lowering chronic inflammation in PLWH. Such therapies can potentially reduce atherosclerosis, cardiovascular disease, and thrombosis rates in PLWH and thus overall mortality in this population.

The Gut Microbiome, Microbial Metabolites, and Cardiovascular Disease in People Living with HIV

PURPOSE OF REVIEW

To synthesize recent evidence relating the gut microbiome and microbial metabolites to cardiovascular disease (CVD) in people living with HIV (PLWH).

RECENT FINDINGS

A few cross-sectional studies have reported on the gut microbiome and cardiovascular outcomes in the context of HIV, with no consistent patterns emerging. The largest such study found that gut Fusobacterium was associated with carotid artery plaque. More studies have evaluated microbial metabolite trimethylamine N-oxide with CVD risk in PLWH, but results were inconsistent, with recent prospective analyses showing null effects. Studies of other microbial metabolites are scarce. Microbial translocation biomarkers (e.g., lipopolysaccharide binding protein) have been related to incident CVD in PLWH. Microbial translocation may increase CVD risk in PLWH, but there is insufficient and/or inconsistent evidence regarding specific microbial species and microbial metabolites associated with cardiovascular outcomes in PLWH. Further research is needed in large prospective studies integrating the gut microbiome, microbial translocation, and microbial metabolites with cardiovascular outcomes in PLWH.

Trained immunity is induced in humans after immunization with an adenoviral vector COVID-19 vaccine

BackgroundHeterologous effects of vaccines are mediated by "trained immunity," whereby myeloid cells are metabolically and epigenetically reprogrammed, resulting in heightened responses to subsequent insults. Adenovirus vaccine vector has been reported to induce trained immunity in mice. Therefore, we sought to determine whether the ChAdOx1 nCoV-19 vaccine (AZD1222), which uses an adenoviral vector, could induce trained immunity in vivo in humans.MethodsTen healthy volunteers donated blood on the day before receiving the ChAdOx1 nCoV-19 vaccine and on days 14, 56, and 83 after vaccination. Monocytes were purified from PBMCs, cell phenotype was determined by flow cytometry, expression of metabolic enzymes was quantified by RT-qPCR, and production of cytokines and chemokines in response to stimulation ex vivo was analyzed by multiplex ELISA.ResultsMonocyte frequency and count were increased in peripheral blood up to 3 months after vaccination compared with their own prevaccine controls. Expression of HLA-DR, CD40, and CD80 was enhanced on monocytes for up to 3 months following vaccination. Moreover, monocytes had increased expression of glycolysis-associated enzymes 2 months after vaccination. Upon stimulation ex vivo with unrelated antigens, monocytes produced increased IL-1β, IL-6, IL-10, CXCL1, and MIP-1α and decreased TNF, compared with prevaccine controls. Resting monocytes produced more IFN-γ, IL-18, and MCP-1 up to 3 months after vaccination compared with prevaccine controls.ConclusionThese data provide evidence for the induction of trained immunity following a single dose of the ChAdOx1 nCoV-19 vaccine.FundingThis work was funded by the Health Research Board (EIA-2019-010) and Science Foundation Ireland Strategic Partnership Programme (proposal ID 20/SPP/3685).

Distinct phenotype of neutrophil, monocyte, and eosinophil populations indicates altered myelopoiesis in a subset of patients with multiple myeloma

Hematologic malignancies, including multiple myeloma (MM), promote systemic immune dysregulation resulting in an alteration and increased plasticity of myeloid cell subsets. To determine the heterogeneity of the myeloid cell compartment in the peripheral blood of patients with MM, we performed a detailed investigation of the phenotype and function of myeloid subpopulations. We report that a subset of MM patients exhibits a specific myeloid cell phenotype indicative of altered myelopoiesis characterized by significant changes in the properties of circulating granulocytic, monocytic, and eosinophilic populations. The subset, referred to as MM2, is defined by a markedly elevated level of CD64 (FcγRI) on the surface of circulating neutrophils. Compared to healthy controls or MM1 patients displaying intermediate levels of CD64, neutrophils from MM2 patients exhibit a less differentiated phenotype, low levels of CD10 and CXC chemokine receptor 2 (CXCR2), increased capacity for the production of mitochondrial reactive oxygen species, and an expansion of CD16^neg immature neutrophil subset. Classical and patrolling monocytes from MM2 patients express elevated levels of CD64 and activation markers. MM2 eosinophils display lower levels of C-C Chemokine receptor 3 (CCR3), Toll-like receptor 4 (TLR4, CD284), and tissue factor (TF, CD142). The MM2 (CD64^high) phenotype is independent of age, race, sex, and treatment type. Characteristic features of the MM2 (CD64^high) phenotype are associated with myeloma-defining events including elevated involved/uninvolved immunoglobulin free light chain (FLC) ratio at diagnosis. Detailed characterization of the altered myeloid phenotype in multiple myeloma will likely facilitate the identification of patients with an increased risk of disease progression and open new avenues for the rational design of novel therapeutic approaches.

The Effect of PEGylated Graphene Oxide Nanoparticles on the Th17-Polarization of Activated T Helpers

We investigated the direct effect of PEGylated graphene oxide (P-GO) nanoparticles on the differentiation, viability, and cytokine profile of activated T helper type 17 (Th17) in vitro. The subject of the study were cultures of "naive" T-helpers (CD4+) isolated by immunomagnetic separation and polarized into the Th17 phenotype with a TCR activator and cytokines. It was found that P-GO at low concentrations (5 µg/mL) had no effect on the parameters studied. The presence of high concentrations of P-GO in T-helper cultures (25 μg/mL) did not affect the number and viability of these cells. However, the percentage of proliferating T-helpers in these cultures was reduced. GO nanoparticles modified with linear polyethylene glycol (PEG) significantly increased the percentage of Th17/22 cells in cultures of Th17-polarized T helpers and the production of IFN-γ, whereas those modified with branched PEG suppressed the synthesis of IL-17. Thus, a low concentration of PEGylated GO nanoparticles (5 μg/mL), in contrast to a concentration of 25 μg/mL, has no effect on the Th17-polarization of T helpers, allowing their further use for in-depth studies of the functions of T lymphocytes and other immune cells. Overall, we have studied for the first time the direct effect of P-GO nanoparticles on the conversion of T helper cells to the Th17 phenotype.

Cognitive impairment and biomarkers of gut microbial translocation in testicular germ cell tumor survivors

Background

Survivors of testicular germ cell tumors (GCT) may suffer from late cognitive impairment. We hypothesized that disruption of intestinal barrier during chemotherapy and/or radiotherapy may be a contributing factor of cognitive dysfunction within the gut-blood-brain axis.

Methods

GCT survivors (N = 142) from National Cancer Institute of Slovakia completed the Functional Assessment of Cancer Therapy Cognitive Function questionnaires during their annual follow-up visit at 9-year median (range 4-32). Biomarkers of gut microbial translocation and dysbiosis high mobility group box-1 (HMGB-1), lipopolysaccharide, d-lactate and sCD14 were measured from peripheral blood obtained during the same visit. Each questionnaire score was correlated with biomarkers. Survivors were treated with orchiectomy only (N = 17), cisplatin-based chemotherapy (N = 108), radiotherapy to the retroperitoneum (N = 11) or both (N = 6).

Results

GCT survivors with higher sCD14 (above median) had worse cognitive function perceived by others (CogOth domain) (mean ± SEM; 14.6 ± 0.25 vs 15.4 ± 0.25, p = 0.019), lower perceived cognitive abilities (CogPCA domain) (20.0 ± 0.74 vs 23.4 ± 0.73, p = 0.025) and lower overall cognitive function score (109.2 ± 0.74 vs 116.7 ± 1.90, p = 0.021). There were no significant cognitive declines associated with HMGB-1, d-lactate and lipopolysaccharide. Survivors treated with ≥ 400mg/m2 vs < 400mg/m2 of cisplatin-based chemotherapy had a higher lipopolysaccharide (567.8 μg/L ± 42.7 vs 462.9 μg/L ± 51.9, (p = 0.03).

Conclusions

sCD14 is a marker of monocytic activation by lipopolysaccharide and may also serve as a promising biomarker of cognitive impairment in long-term cancer survivors. While chemotherapy and radiotherapy-induced intestinal injury may be the underlying mechanism, further research using animal models and larger patient cohorts are needed to explore the pathogenesis of cognitive impairment in GCT survivors within the gut-brain axis.

Intestinal Injury Biomarkers Predict Mortality in Pediatric Severe Malaria

Severe malaria (SM) increases the risk of invasive bacterial infection, and there is evidence to suggest increased gastrointestinal permeability. Studies have shown sequestration of infected erythrocytes in intestinal microvasculature, and in vivo studies of rectal mucosa have demonstrated disruption of microvascular blood flow. However, the extent of intestinal injury in pediatric malaria is not well characterized. In this study, two serum biomarkers of intestinal injury, trefoil factor 3 (TFF3) and intestinal fatty acid binding protein (I-FABP), were analyzed in 598 children with SM and 120 healthy community children (CC), 6 months to 4 years of age. Serum was collected at enrollment and 1 month for laboratory studies, and participants were monitored for 12 months. Intestinal injury biomarkers were significantly elevated in children with SM, with 18.1% having levels of TFF3 and/or I-FABP greater than the 99th percentile of CC levels. TFF3 levels continued to be elevated at 1 month, while I-FABP levels were comparable to CC levels. Both markers predicted in-hospital mortality {odds ratio (OR) (95% confidence interval [CI]), 4.4 (2.7, 7.3) and 2.3 (1.7, 3.1)} for a natural log increase in TFF3 and I-FABP, respectively. TFF3 was also associated with postdischarge mortality (OR, 2.43 [95% CI, 1.1, 4.8]). Intestinal injury was associated with acute kidney injury (AKI), acidosis (P < 0.001 for both), and angiopoietin 2, a maker of endothelial activation. In conclusion, intestinal injury is common in pediatric severe malaria and is associated with an increased mortality. It is strongly associated with AKI, acidosis, and endothelial activation. IMPORTANCE In children with severe malaria, intestinal injury is a common complication associated with increased mortality. Intestinal injury is associated with acute kidney injury, acidosis, and endothelial activation. Interventions promoting intestinal regeneration and repair represent novel approaches to improve outcomes.

Factors Associated With Systemic Immune Activation Indices in a Global Primary Cardiovascular Disease Prevention Cohort of People With Human Immunodeficiency Virus on Antiretroviral Therapy

BACKGROUND

Among antiretroviral therapy (ART)-treated people with human immunodeficiency virus (PWH), persistent systemic immune activation contributes to atherogenesis atherosclerotic, cardiovascular disease (CVD) events, and mortality. Factors associated with key immune activation indices have not previously been characterized among a global primary CVD prevention cohort of PWH.

METHODS

Leveraging baseline Randomized Trial to Prevent Vascular Events in HIV (REPRIEVE) data, we evaluated factors associated with soluble CD14 (sCD14) and oxidized low-density lipoprotein (oxLDL).

RESULTS

The primary analysis cohort included 4907 participants from 5 global-burden-of-disease regions (38% female, 48% Black, median age 50 years). In fully adjusted models for sCD14, female sex and White race (among those in high-income regions) were associated with higher sCD14 levels, while higher body mass index (BMI) and current use of nucleoside reverse transcriptase inhibitor + integrase strand transfer inhibitor ART were associated with lower sCD14 levels. In fully adjusted models for oxLDL, male sex, residence in high-income regions, White race (among those in high-income regions), and higher BMI were associated with higher oxLDL levels. In a subanalysis cohort of 1396 women with HIV, increased reproductive age was associated with higher sCD14 levels but not with higher oxLDL levels.

CONCLUSIONS

Factors associated with sCD14 and oxLDL, 2 key indices of immune-mediated CVD risk, differ. Future studies will elucidate ways in which medications (eg, statins) and behavioral modifications influence sCD14 and oxLDL and the extent to which dampening of these markers mediates CVD-protective effects.

CLINICAL TRIALS REGISTRATION

NCT0234429.

Resistin Modulates the Functional Activity of Colostral Macrophages from Mothers with Obesity and Diabetes

Background: Obesity and diabetes are major public health problems. Resistin is an adipokine that links the two diseases. There are few reports regarding colostrum cells and resistin from mothers with obesity and diabetes. Thus, this study aimed to determine the functional activity of macrophages present in the breast milk and colostrum of diabetic mothers with obesity and the effects of resistin on these cells. Methods: The women were divided according to BMI and glycemic status into normal weight non-diabetic, obese non-diabetic, normal weight type 2 diabetic, or obese type 2 diabetic groups. ELISA determined the resistin in colostrum. The cell subsets and apoptosis were determined by flow cytometry and the functional activity of cells by fluorescence microscopy. Results: The resistin levels were higher in the colostrum from diabetic mothers with obesity. The frequencies of CD14+ cells and cells expressing CD95+, independent of resistin treatment, were higher in the colostrum from diabetic mothers with obesity. The frequency of cells expressing CD14+CD95+ was higher in cells not treated with resistin in the colostrum from diabetic mothers with obesity. Apoptosis, irrespective of the presence of resistin, increased, whereas microbicidal activity decreased in cells from diabetic mothers with obesity. Conclusion: The data suggest that hyperglycemia associated with low-grade inflammation caused by obesity affects the percentage of cells expressing CD14+CD95+, death by apoptosis, and microbicidal indices; meanwhile, resistin restored the microbicidal activity of colostrum cells.

Gut permeability may be associated with periprosthetic joint infection after total hip and knee arthroplasty

A growing number of recent investigations on the human genome, gut microbiome, and proteomics suggests that the loss of mucosal barrier function, particularly in the gastrointestinal tract, may substantially affect antigen trafficking, ultimately influencing the close bidirectional interaction between the gut microbiome and the immune system. This cross-talk is highly influential in shaping the host immune system function and ultimately affecting the outcome of interventions. We hypothesized that the loss of mucosal barrier in the gut may be associatedto acute and chronic periprosthetic joint infections (PJI). Zonulin, soluble CD14 (sCD14), and lipopolysaccharide (LPS) were tested in plasma as part of a prospective cohort study of patients undergoing primary arthroplasty or revision arthroplasty because of an aseptic failure or PJI (as defined by the 2018 criteria). All blood samples were collected before antibiotic administration. Samples were tested using commercially available enzyme-linked immunosorbent assays as markers for gut permeability. A total of 134 patients were included in the study of which 44 patients had PJI (30 chronic and 14 acute), and the remaining 90 patients were categorized as non-infected that included 64 patients revised for aseptic failure, and 26 patients undergoing primary total joint arthroplasty. Both Zonulin (7.642 ± 6.077 ng/mL vs 4.560 ± 3.833 ng/mL; p < 0.001) and sCD14 levels (555.721 ± 216.659 ng/mL vs 396.872 ± 247.920 ng/mL; p = 0.003) were significantly elevated in the PJI group compared to non-infected cases. Higher levels of Zonulin were found in acute infections compared to chronic PJI (11.595 ± 6.722 ng/mL vs. 5.798 ± 4.841 ng/mL; p = 0.005). This prospective study reveals a possible link between gut permeability and the ‘gut-immune-joint axis’ in PJI. If this association continues to be borne out with a larger cohort and more in-depth analysis, it will have a clinically significant implication in managing patients with PJI. It may be that in addition to the administration of antimicrobials, patients with PJI and other orthopaedic infections may benefit from administration of gastrointestinal modulators such as pro and prebiotics.

Neuropathogenesis of HIV-1: insights from across the spectrum of acute through long-term treated infection

This review outlines the neuropathogenesis of HIV, from initial HIV entry into the central nervous system (CNS) to chronic infection, focusing on key advancements in the last 5 years. Discoveries regarding acute HIV infection reveal timing and mechanisms of early HIV entry and replication in the CNS, early inflammatory responses, and establishment of genetically distinct viral reservoirs in the brain. Recent studies additionally explore how chronic HIV infection is maintained in the CNS, examining how the virus remains in a latent "hidden" state in diverse cells in the brain, and how this leads to sustained pathological inflammatory responses. Despite viral suppression with antiretroviral therapy, HIV can persist and even replicate in the CNS, and associate with ongoing neuropathology including CD8 + T-lymphocyte mediated encephalitis. Crucial investigation to advance our understanding of the immune mechanisms that both control viral infection and lead to pathological consequences in the brain is necessary to develop treatments to optimize long-term neurologic health in people living with HIV.

Soluble CD14 is subtype-dependent in serum but not in cerebrospinal fluid in people with HIV

Monocytes and macrophages activation are crucial in human immunodeficiency virus (HIV) central nervous system (CNS) infection and HIV associated neurocognitive disorders (HAND) pathogenesis. The soluble form of CD14 (sCD14) is a marker of monocyte activation. We hypothesized that sCD14 levels would be lower in people with HIV-1 subtype C (HIV-1C) than in HIV-1B owing to a variant Tat cysteine dimotif (C30S31) with reduced chemotactic activity. A total of 68 paired cerebrospinal fluid (CSF) and blood samples from people with HIV (PWH); 27 samples of the HIV-1B subtype and 40 of the non-B HIV-1 subtypes (including 26,HIV-1C), and 18 HIV-negative controls were included. sCD14 levels were quantified using a high-sensitivity enzyme-linked immunosorbent assay. sCD14 increase in serum, but not in CSF, was higher in samples from HIV-1B than HIV-1C (p = 0.002; Cohen's d, 0.7). CSF or serum sCD14 values were not correlated with global deficit score or specific cognitive domains. The impact of HIV-1 on monocyte stimulation biomarkers evaluated by sCD14 in serum was subtype-dependent, higher in HIV-1B than HIV-1C, consistent with reduced chemotactic activity as hypothesized.

Monocyte count and soluble markers of monocyte activation in people living with HIV and uninfected controls

Background

Monocytes play an important role in inflammation, and monocytosis and monocyte activation are features of chronic inflammation. We aimed to investigate if HIV status was associated with monocyte count and monocyte activation and to assess the relationship between monocyte count and monocyte activation markers and HIV-related factors.

Methods

Persons living with HIV (PLWH) with measured monocyte count and sCD14 and sCD163 were included from the Copenhagen Comorbidity in HIV infection (COCOMO) study and matched 1:5 on sex and age with uninfected controls. In addition, 74 uninfected individuals from COCOMO with measured sCD14 and sCD163 were included. Identical protocols and equipment were used to determine monocyte counts and monocyte activation in PLWH and uninfected controls. Linear regression adjusted for age, sex, smoking and waist-to-hip-ratio was used to analyze the association between possible risk factors and monocyte outcomes.

Results

We included 871 PLWH and 4355 uninfected controls. PLWH had − 0.021 [− 0.031 − 0.011] × 10⁹/L) lower monocyte count than uninfected controls, and in adjusted analyses HIV status was independently associated with − 0.035 [− 0.045, − 0.025] × 10⁹/L lower monocyte count. In contrast, PLWH had higher sCD163 and sCD14 concentrations than uninfected controls. After adjustment, HIV-status was associated with higher sCD14 and sCD163 concentrations (588 [325, 851] ng/ml, and 194 [57, 330] ng/ml, respectively).

Conclusion

PLWH had lower monocyte counts than controls, but the absolute difference was small, and any clinical impact is likely limited. In contrast, concentrations of monocyte activation markers, previously implicated as drivers of non-AIDS comorbidity, were higher in PLWH than in controls.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07450-y.

Recurrent Respiratory Syncytial Virus Infection in a CD14-Deficient Patient

BACKGROUND

Recurrent respiratory syncytial virus (RSV) infection requiring hospitalization is rare and the underlying mechanism is unknown. We aimed to determine the role of CD14-mediated immunity in the pathogenesis of recurrent RSV infection.

METHODS

We performed genotyping and longitudinal immunophenotyping of the first patient with a genetic CD14 deficiency who developed recurrent RSV infection. We analyzed gene expression profiles and interleukin (IL)-6 production by patient peripheral blood mononuclear cells in response to RSV pre- and post-fusion (F) protein. We generated CD14-deficient human nasal epithelial cells cultured at air-liquid interface (HNEC-ALI) of patient-derived cells and after CRISPR-based gene editing of control cells. We analyzed viral replication upon RSV infection.

RESULTS

Sanger sequencing revealed a homozygous single-nucleotide deletion in CD14, resulting in absence of the CD14 protein in the index patient. In vitro, viral replication was similar in wild-type and CD14-/- HNEC-ALI. Loss of immune cell CD14 led to impaired cytokine and chemokine responses to RSV pre- and post-F protein, characterized by absence of IL-6 production.

CONCLUSIONS

We report an association of recurrent RSV bronchiolitis with a loss of CD14 function in immune cells. Lack of CD14 function led to defective immune responses to RSV pre- and post-F protein without a change in viral replication.

Proteomic Profiling and T Cell Receptor Usage of Abacavir Susceptible Subjects

Type B adverse drug reactions (ADRs) represent a significant threat as their occurrence arises unpredictable and despite proper application of the drug. The severe immune reaction Abacavir Hypersensitivity Syndrome (AHS) that arises in HIV⁺ patients treated with the antiretroviral drug Abacavir (ABC) strongly correlates to the presence of the human leukocyte antigen (HLA) genotype HLA-B*57:01 and discriminates HLA-B*57:01⁺ HIV⁺ patients from ABC treatment. However, not all HLA-B*57:01⁺ HIV⁺ patients are affected by AHS, implying the involvement of further patient-specific factors in the development of AHS. The establishment of a reliable assay to classify HLA-B*57:01 carriers as ABC sensitive or ABC tolerant allowed to investigate the T cell receptor (TCR) Vβ chain repertoire of effector cells and revealed Vβ6 and Vβ24 as potential public TCRs in ABC sensitive HLA-B*57:01 carriers. Furthermore, distinct effects of ABC on the cellular proteome of ABC sensitive and tolerant volunteers were observed and suggest enhanced activation and maturation of dentritic cells (DC) in ABC sensitive volunteers. Analysis of ABC-naïve cellular proteomes identified the T cell immune regulator 1 (TCIRG1) as a potential prognostic biomarker for ABC susceptibility and the involvement of significantly upregulated proteins, particularly in peptide processing, antigen presentation, interferon (IFN), and cytokine regulation.

Elevated Cerebrospinal Fluid Anti-CD4 Autoantibody Levels in HIV Associate with Neuroinflammation

The mechanisms of persistent central nervous system (CNS) inflammation in people with HIV (PWH) despite effective antiretroviral therapy (ART) are not fully understood. We have recently shown that plasma anti-CD4 IgGs contribute to poor CD4⁺ T cell recovery during suppressive ART via antibody-mediated cytotoxicity (ADCC) against CD4⁺ T cells, and that plasma anti-CD4 IgG levels are associated with worse cognitive performance and specific brain area atrophy. However, the role of anti-CD4 IgGs in neuroinflammation remains unclear. In the current study, plasma and cerebrospinal fluid (CSF) samples from 31 ART-naive and 26 treated, virologically suppressed PWH, along with 16 HIV-seronegative controls, were evaluated for CSF levels of anti-CD4 IgG, white blood cell (WBC) counts, soluble biomarkers of neuroinflammation, and neurofilament light chain (NfL). We found that 37% of the PWH exhibited elevated CSF anti-CD4 IgG levels, but few or none of the PWH were observed with elevated CSF anti-CD4 IgM, anti-CD8 IgG, or anti-double-strand DNA IgG. CSF anti-CD4 IgG levels in PWH were directly correlated with neuroinflammation (WBC counts, neopterin, and markers of myeloid cell activation), but not with CSF NfL levels. Using cells from one immune nonresponder to ART, we generated a pathogenic anti-CD4 monoclonal IgG (JF19) presenting with ADCC activity; JF19 induced the production of soluble CD14 (sCD14) and interleukin-8 (IL-8) in human primary monocyte-derived macrophages via CD4 binding in vitro. This study demonstrates for the first time that elevated CSF anti-CD4 IgG levels present in a subgroup of PWH which may play a role in neuroinflammation in HIV.

IMPORTANCE This study reports that an autoantibody presents in the CNS of HIV patients and that its levels in the CSF correlate with some markers of neuroinflammation.

Changes in Inflammatory and Atherogenesis Biomarkers With the 2-Drug Regimen Dolutegravir Plus Lamivudine in Antiretroviral Therapy–Experienced, Virologically Suppressed People With HIV-1: A Systematic Literature Review

Background

The 2-drug regimen dolutegravir plus lamivudine has demonstrated long-term noninferior efficacy vs 3-/4-drug regimens (3/4DRs) in phase 3 trials. This systematic literature review summarizes clinical trial and real-world evidence evaluating impact of dolutegravir plus lamivudine on inflammatory and atherogenesis biomarkers in people with human immunodeficiency virus type 1 (PWH).

Methods

Using Ovid MEDLINE, Embase, PubMed, and Cochrane library databases and conference proceedings, we searched for studies published from 1 January 2013 to 14 July 2021, reporting changes in inflammatory and atherogenesis biomarkers with dolutegravir plus lamivudine in antiretroviral therapy–experienced, virologically suppressed PWH aged ≥18 years.

Results

Four records representing 2 randomized controlled trials (RCTs) and 6 records of real-world evidence met eligibility criteria. All real-world studies evaluated CD4⁺/CD8⁺ ratio, while only 1 assessed inflammatory biomarkers. Across both RCTs, no consistent pattern of change in biomarkers was observed between dolutegravir/lamivudine and 3/4DR comparators. There were significant changes in soluble CD14 favoring dolutegravir/lamivudine in TANGO at weeks 48 and 144 and SALSA at week 48, and in interleukin-6 favoring the control group in TANGO at weeks 48 and 144. In the real-world study evaluating inflammatory biomarkers, median soluble CD14 significantly decreased 48 weeks postswitch to dolutegravir plus lamivudine (P < .001), while other biomarkers remained stable. In all 6 real-world studies, increases in CD4⁺/CD8⁺ ratio were reported after switch to dolutegravir plus lamivudine (follow-up, 12–60 months).

Conclusions

Results show that dolutegravir plus lamivudine has a comparable impact on inflammatory and atherogenesis biomarkers vs 3/4DRs, with no consistent pattern of change after switch in virologically suppressed PWH.