Perinatally acquired HIV (PHIV) and antiretroviral therapy (ART) can alter innate immune cells, (monocytes and natural killer [NK] cells) which are important in the pathogenesis of cardiovascular disease (CVD). We compare cardiovascular biomarkers and immune signatures between adolescents with PHIV (APHIV) on suppressive ART and HIV-unexposed, adolescents without HIV in Uganda. Carotid intima-media thickness (IMT) is increased in APHIV, suggesting a higher CVD risk. Flow cytometry analysis reveals greater activation, memory, and migratory capabilities of NK cells, and increased pro-inflammatory intermediate monocytes in APHIV, and these observations are supported by transcriptomics. Many of these innate immune cell subsets are associated with carotid IMT. Plasma oxidized-LDL (Ox-LDL) is significantly lower among APHIV, and negatively correlates with pro-inflammatory, memory-like NK subsets. We demonstrate increased uptake of Ox-LDL by macrophages in the presence of activated, memory-like NK cells in vitro, suggesting a possible mechanism for greater CVD risk in APHIV. Collectively, our data demonstrate associations between dysregulated NK cell signatures and increased CVD risk among APHIV.
Oral tenofovir is a key antiretroviral used for treatment and pre-exposure prophylaxis (PrEP) of human immunodeficiency virus (HIV). A gel form has been tested for vaginal and rectal PrEP. We have shown that 7 days of tenofovir 1% gel had broad-ranging effects on gene expression in the rectum, especially suppression of anti-inflammatory mediators and induction of cell proliferation. Similarly, oral PrEP induced type I/III interferon-stimulated genes in the gut. It is unknown how long these effects last and whether they occur in other relevant body compartments. We measured the transcriptomes and proteomes of tissue samples obtained before and after daily topical tenofovir 1% gel application for 14 days (Microbicide Trials Network [MTN]-014 trial, rectal and vaginal) or 56 days (MTN-017 trial, rectal). While many changes seen after 7 days diminish after 14 and 56 days, some remain, notably increases in cell proliferation- and type I/III interferon-related genes. Vaginal gel uniquely induces changes related to epithelial-mesenchymal transition and angiogenesis. Induction of type I/III interferon-related genes is the most consistent and persistent mucosal response to tenofovir, occurring after both oral and topical use and at all tested time points. Hypothetically, interferon induction could improve antiviral efficacy, but also contribute to an increased chronic disease burden in people with HIV.IMPORTANCEAnalyzing gene expression data from three separate clinical trials, we find that the antiretroviral drug tenofovir, which belongs to the class of nucleotide analogue reverse transcriptase inhibitors, induces the type I/III interferon system of innate immunity in the mucosa. This effect occurs in the absence of HIV infection and manifests itself over various treatment durations and after both oral and topical drug delivery. Tenofovir and other related medications are important components of long-term antiretroviral treatment taken by people living with HIV. Therefore, this unexpected immunological effect might need to be considered as a potential contributor to comorbidities in people living with HIV, as well as an immunopharmacological co-factor when testing novel HIV cure interventions.CLINICAL TRIALSThis study is registered with ClinicalTrials.gov as NCT01768962, NCT01687218, and NCT01232803.
Chronic skin inflammation is sustained by reciprocal interactions between epidermal dysfunction and immune activation, yet whether epithelial state actively governs restoration of tissue homeostasis remains unclear. Using a murine model of inflammatory skin disease, we modulated epidermal lipid metabolism and examined its effects on tissue organization. Transcriptomic profiling revealed coordinated reversal of inflammatory, metabolic, and structural gene programs accompanied by normalization of epidermal architecture. Single-cell RNA sequencing showed that this remodeling was concentrated in differentiated keratinocytes, with suppression of IL-17 and neutrophil-associated responses and restoration of barrier and mitochondrial-lipid programs, while stromal and myeloid compartments displayed secondary adaptation. Cross-species analysis demonstrated that resolution-associated gene networks are inversely regulated in human psoriasis. Integrated proteomic and transcriptomic analyses further identified a conserved epithelial regulatory triad whose concordant regulation in psoriasis and atopic dermatitis, and whose in vivo silencing, establish mechanistic control of disease severity. Together, these findings indicate that inflammatory resolution reflects reorganization of epidermal transcriptional networks and position epithelial state as a determinant of inflammatory persistence.
The immune response to COVID-19 vaccines is diminished in older individuals. To understand the underlying immunobiology, we analyzed single-cell RNA-seq data from PBMCs of SARS-CoV-2 naive nursing home residents with varying humoral responses following BNT162b2 vaccination and validated via flow cytometry. Responders (R) (>4500 AU/mL anti-spike titers) showed enrichment for naive B cell (IGHD, BACH2, CD22) and naive CD4 T cell and early T follicular helper (Tfh)-related genes (CCR7, TCF7, LEF1, IL6ST, and TGFBR2). Non-responders (NR) (<20 AU/mL) displayed elevated markers of T cell senescence (KLRG1, CCL4, CCL5, and IL32), immune exhaustion (PD-1), and inflammation (TNF-α, IFN-γ). Flow cytometry revealed reduced CD4 T and B cell frequencies but higher CD8 T and NK cells in NR. Despite reduced B cell frequency, NR upregulated plasma B cell genes (PRDM1, XPB1, IRF4), suggesting dysregulated B cell differentiation. Our findings point to impaired lymphocyte responses and increased immunosenescence in NR, emphasizing the need for enhanced vaccine strategies in aging populations.
Alpha-tocopherol (vitamin E) is a plant-derived dietary lipid that is essential for the health of most animals, including humans. Originally discovered as a fertility factor in rodents, the primary health-promoting properties of the vitamin in humans was shown to be protection of neuromuscular functions. Heritable vitamin E deficiency manifests in spinocerebellar ataxia that can be stabilized by timely supplementation with high-dose α-tocopherol. The molecular basis for α-tocopherol's biological activities has been attributed primarily to the vitamin's efficacy in preventing lipid peroxidation in membranes and lipoproteins, but the possibility that the vitamin possesses additional biological activities has been postulated and debated in the literature without conclusive resolution. We designed and synthesized a novel analog of α-tocopherol, 6-hydroxymethyl α-tocopherol (6-HMTC), which retains most of the vitamin's structural, physical, and biochemical properties, yet lacks measurable radical-trapping antioxidant activity. 6-HMTC bound to the tocopherol transfer protein with high (nanomolar) affinity, like that of the natural vitamin, attesting to the analog's preservation of structural integrity. Yet, 6-HMTC did not inhibit lipid peroxidation or associated ferroptotic cell death. Notably, 6-HMTC modulated the expression of some genes in a manner essentially identical to that exhibited by α-tocopherol. These findings support the notion that α-tocopherol modulates gene expression via an antioxidant-independent mechanism.
ObjectiveMicroglia/macrophages line the border of demyelinated lesions in both cerebral white matter and the cortex in the brains of multiple sclerosis patients. Microglia/macrophages associated with chronic white matter lesions are thought to be responsible for slow lesion expansion and disability progression in progressive multiple sclerosis, whereas those lining gray matter lesions are less studied. Profiling these microglia/macrophages could help to focus therapies on genes or pathways specific to lesion expansion and disease progression.MethodsWe compared the morphology and transcript profiles of microglia/macrophages associated with borders of white matter (WM line) and subpial gray matter lesions (GM line) using laser capture microscopy. We performed RNA sequencing on isolated cells followed by immunocytochemistry to determine the distribution of translational products of transcripts increased in WM line microglia.ResultsCells in the WM line appear activated, with shorter processes and larger cell bodies, whereas those in the GM line appear more homeostatic, with smaller cell bodies and multiple thin processes. Transcript profiling revealed 176 genes in WM lines and 111 genes in GM lines as differentially expressed. Transcripts associated with immune activation and iron homeostasis were increased in WM line microglia, whereas genes belonging to the canonical Wnt signaling pathway were increased in GM line microglia.InterpretationWe propose that the mechanisms of demyelination and dynamics of lesion expansion are responsible for differential transcript expression in WM lines and GM lines, and posit that increased expression of the Fc epsilon receptor, spleen tyrosine kinase, and Bruton's tyrosine kinase, play a key role in regulating microglia/macrophage function at the border of chronic active white matter lesions. ANN NEUROL 2024
Background Vaccines and vaccine boosting have blunted excess morbidity and mortality from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in older nursing home residents (NHR). However, the impact of repeated vaccination on the T-cell response based on biological sex and prior infection of NHR remain understudied.Methods We examined T-cell responses to SARS-CoV-2 mRNA vaccines in a cohort of NHR and healthcare workers (HCW) over 2 years. We used interferon-gamma ELIspot and flow cytometry to assess T-cell response before, 2 weeks, and 6 months after the initial series and each of 2 booster vaccines. We analyzed these data longitudinally with mixed-effect modeling and also examined subsets of our cohorts for additional changes in T-cell effector function.Results Prior SARS-CoV-2 infection and female sex contributed to higher T-cell response in NHR but not HCW. When looking across time points, NHR but not HCW with prior infection had significantly higher T-cell responses than infection-naive subjects. These patterns of response were maintained across multiple booster vaccinations.Conclusions These results suggest that the age, multimorbidity, and/or frailty of the NHR cohort may accentuate sex and infection status differences in T-cell response to mRNA vaccination. T-cells responses in nursing home residents (NHR) and health care workers (HCW) after SARS-CoV-2 mRNA vaccination show that both groups have vaccine-induced responses, but prior infection and female sex contribute to higher responses in NHR but not HCW.
IntroductionSelf-antigens abnormally expressed on tumors, such as MUC1, have been targeted by therapeutic cancer vaccines. We recently assessed in two clinical trials in a preventative setting whether immunity induced with a MUC1 peptide vaccine could reduce high colon cancer risk in individuals with a history of premalignant colon adenomas. In both trials, there were immune responders and non-responders to the vaccine.MethodsHere we used PBMC pre-vaccination and 2 weeks after the first vaccine of responders and non-responders selected from both trials to identify early biomarkers of immune response involved in long-term memory generation and prevention of adenoma recurrence. We performed flow cytometry, phosflow, and differential gene expression analyses on PBMCs collected from MUC1 vaccine responders and non-responders pre-vaccination and two weeks after the first of three vaccine doses.ResultsMUC1 vaccine responders had higher frequencies of CD4 cells pre-vaccination, increased expression of CD40L on CD8 and CD4 T-cells, and a greater increase in ICOS expression on CD8 T-cells. Differential gene expression analysis revealed that iCOSL, PI3K AKT MTOR, and B-cell signaling pathways are activated early in response to the MUC1 vaccine. We identified six specific transcripts involved in elevated antigen presentation, B-cell activation, and NF-κB1 activation that were directly linked to finding antibody response at week 12. Finally, a model using these transcripts was able to predict non-responders with accuracy.DiscussionThese findings suggest that individuals who can be predicted to respond to the MUC1 vaccine, and potentially other vaccines, have greater readiness in all immune compartments to present and respond to antigens. Predictive biomarkers of MUC1 vaccine response may lead to more effective vaccines tailored to individuals with high risk for cancer but with varying immune fitness.
Abstract Background/Introduction Mineralocorticoid receptor (MR) antagonists (MRA) are beneficial in cardiorenal outcomes in randomized controlled trials but the mechanisms are unclear. MAGMA was an NHLBI sponsored randomized, double-blind, placebo controlled, 12-month trial comparing Spironolactone (n = 37) vs. placebo (n = 42) in Type 2 diabetics with CKD stages 3-4 on maximal renin-angiotensin system (RAS) blockade and a prior atherosclerotic event and/or left ventricular (LV) hypertrophy. The primary outcome of percent (%) change in total aortic wall volume (TWV) at 12 months, measured by magnetic resonance imaging (MRI), was significantly reduced by Spironolactone. Purpose/Originality The purpose of this analysis was to understand mechanistic pathways of MRAs using a multi-omics approach that could help tease out molecular mechanisms of benefit. Revealing for the first time which of these integrated pathways are predictive of the primary outcome will help design treatments for targeted interventions. Methods Plasma and peripheral blood mononuclear cells from patients randomized to Spironolactone or placebo at baseline and 3-months were measured for aptamer-based proteomic biomarkers (7,596 proteins) and 10-X platform-based single-cell RNA-sequencing (scRNAseq), respectively. Pre-selected candidate predictors were used as inputs of a predictive model of changes of TWV. We fit a Mixed-Multivariate Random Forest (RF) model, a variation of the RF supervised tree-based machine learning method to take the experimental design into account in the regression formulation. The two sources of "omics predictors" were integrated into a supervised multi-omics model to jointly explain the outcome using an extension of Sparse Generalized Canonical Correlation Analysis (SGCCA). Integrated multiome functional analyses with graphical visualizations were carried out by statistical enrichment analysis using Over Representation Analysis (ORA) and Gene Set Enrichment Analysis (GSEA) against databases of gene ontologies, biological pathways, putative regulatory motifs, proteins, or disease annotations. Results The plasma proteome in response to Spironolactone revealed downregulation of MR targets including fibrosis, immune activation/inflammation, leukocyte activation, proliferation and pathways involved in cytokine stimulation. scRNAseq pathways revealed negative regulation of cytokines production such as IL-2 and redistribution of multiple cell types. Predictors of plaque progression involved cytokine-receptor, complement-coagulation, cell adhesion and axonal guidance targets. Multiome integrated functional analyses results of predictive pathways will be presented. Conclusions The changes in plasma proteomic profile with Spironolactone were consistent with the phenotype of reduced atherosclerosis and downregulation of multiple inflammatory, immune response and profibrotic pathways.
Current pharmacologic treatments for atherosclerosis do not completely protect patients; additional protection can be achieved by dietary modifications, such as a low-cholesterol/low-fat diet (LCLFD), that mediate plaque stabilization and inflammation reduction. However, this lifestyle modification can be challenging for patients. Unfortunately, incomplete understanding of the underlying mechanisms has thwarted efforts to mimic the protective effects of a LCLFD. Here, we report that the tricarboxylic acid cycle intermediate itaconate (ITA), produced by plaque macrophages, is key to diet-induced plaque resolution. ITA is produced by immunoresponsive gene 1 (IRG1), which we observe is highly elevated in myeloid cells of vulnerable plaques and absent from early or stable plaques in mice and humans. We additionally report development of an ITA-conjugated lipid nanoparticle that accumulates in plaque and bone marrow myeloid cells, epigenetically reduces inflammation via H3K27ac deacetylation, and reproduces the therapeutic effects of LCLFD-induced plaque resolution in multiple atherosclerosis models.
BACKGROUND: Persistent mineralocorticoid receptor activation is a pathologic response in type 2 diabetes and chronic kidney disease. Whereas mineralocorticoid receptor antagonists are beneficial in reducing cardiovascular complications, direct mechanistic pathways for these effects in humans are lacking. METHODS: The MAGMA trial (Mineralocorticoid Receptor Antagonism Clinical Evaluation in Atherosclerosis) was a randomized, double-blind, placebo-controlled trial in patients with high-risk type 2 diabetes with chronic kidney disease (not receiving dialysis) on maximum tolerated renin-angiotensin system blockade. The primary end point was change in thoracic aortic wall volume, expressed as absolute or percent value (ΔTWV or ΔPWV), using 3T magnetic resonance imaging at 12 months. Secondary end points were changes in left ventricle (LV) mass; LV fibrosis, measured as a change in myocardial native T1; and 24-hour ambulatory and central aortic blood pressures. Tertiary end points included plasma proteomic changes in 7596 plasma proteins using an aptamer-based assay. RESULTS: A total of 79 patients were randomized to placebo (n=42) or 25 mg of spironolactone daily (n=37). After a modified intent-to-treat, including available baseline data of study end points, patients who completed the trial protocol were included in the final analyses. At the 12-month follow-up, the average change in PWV was 7.1±10.7% in the placebo group and 0.87±10.0% in the spironolactone group ( P =0.028), and ΔTWV was 1.2±1.7 cm 3 in the placebo group and 0.037±1.9 cm 3 in the spironolactone group ( P =0.022). Change in LV mass was 3.1±8.4 g in the placebo group and −5.8±8.4 g in the spironolactone group ( P =0.001). Changes in LV T1 values were significantly different between the placebo and spironolactone groups (26.0±41.9 ms in the placebo group versus a decrease of −10.1±36.3 ms in the spironolactone group; P =6.33×10 −4 ). Mediation analysis revealed that the spironolactone effect on thoracic aortic wall volume and myocardial mass remained significant after adjustment for ambulatory and central blood pressures. Proteomic analysis revealed a dominant effect of spironolactone on pathways involving oxidative stress, inflammation, and leukocyte activation. CONCLUSIONS: Among patients with diabetes with moderate to severe chronic kidney disease at elevated cardiovascular risk, treatment with spironolactone prevented progression of aortic wall volume and resulted in regression of LV mass and favorable alterations in native T1, suggesting amelioration of left-ventricular fibrosis. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT02169089.
Background: The adjuvanted recombinant zoster vaccine (RZV) is highly effective even in adults over 80 years old. The high efficacy of RZV is attributed to its highly reactogenic adjuvant, AS01, but limited studies have been done on AS01's activation of human immune cells. Methods: We stimulated peripheral blood mononuclear cells (PBMC) with AS01 and used flow cytometry and RNA Sequencing (RNAseq) to analyze the impacts on human primary cells. Results: We found that incubation of PBMC with AS01 activated monocytes to a greater extent than any other cell population, including dendritic cells. Both classical and non-classical monocytes demonstrated this activation. RNASeq showed that TNF-alpha and IL1R pathways were highly upregulated in response to AS01 exposure, even in older adults. Conclusions: In a PBMC co-culture, AS01 strongly activates human monocytes to upregulate costimulation markers and induce cytokines that mediate systemic inflammation. Understanding AS01's impacts on human cells opens possibilities to further address the reduced vaccine response associated with aging.
Background: Mineralocorticoid receptor (MR) antagonists (MRA) benefit patients with diabetic chronic kidney disease (CKD) and heart failure, and may act upstream on multiple cardioprotective pathways. The NHLBI-sponsored MAGMA trial, a 12-month, randomized, double-blind, placebo-controlled trial compared Spironolactone vs. placebo in Type 2 diabetics with CKD stages 3-4 on maximal renin-angiotensin system blockade and a prior atherosclerotic event and/or left ventricular (LV) hypertrophy. Methods: Seventy-nine patients were randomized to Spironolactone 25 mg (n = 37) or placebo (n = 42) for 12 months. The primary outcome was % change in total aortic wall volume (TWV) at 12 months by magnetic resonance imaging (MRI). Baseline, 3-month, and 12-month plasma samples were measured for 7,596 protein biomarkers. We used the general linear hypothesis framework and Linear mixed-effect models to generate lists of differentially expressed proteins by effect. A multi-visit matching approach was used to model the association of proteomic expression changes with TWV changes. We fit a Mixed Multivariate Random Forest model to take the experimental design into account and build predictive proteomic predictors associated with primary outcome changes of TWV. Results: Patients had a mean age of 64±8 years with 50% African Americans and 46% women. Spironolactone reduced PWV versus placebo. Plasma proteome revealed downregulation of MR targets including fibrosis, immune activation/inflammation, leukocyte activation, proliferation and pathways involved in cytokine stimulation. Predictors of plaque progression involved cytokine-receptor, complement-coagulation, cell adhesion and axonal guidance targets. Conclusions: The changes in plasma proteomic profile with Spironolactone were consistent with downregulation in multiple inflammatory, immune response and profibrotic pathways. Disclosure A. Vergara-Martel: None. J. Dazard: None. M. Dobre: None. K.A. Connelly: Research Support; AstraZeneca. J. Edwards-Glenn: None. G. Tensol: None. C. Cameron: None. M. Cameron: None. S.G. Al-Kindi: None. R.D. Brook: Advisory Panel; Alnylam Pharmaceuticals, Inc. M.R. Weir: Advisory Panel; AstraZeneca, Bayer Inc., Novo Nordisk, Vifor Pharma Management Ltd., Boehringer-Ingelheim. S. Rajagopalan: Consultant; Novo Nordisk, Bayer Inc. Funding NHLBI
Hematopoietic stem cells (HSCs) adapt to organismal blood production needs by balancing self-renewal and differentiation, adjusting to physiological demands and external stimuli. Although sex differences have been implicated in differential hematopoietic function in males versus females, the mediators responsible for these effects require further study. Here, we characterized hematopoiesis at a steady state and during regeneration following hematopoietic stem cell transplantation (HST). RNA sequencing of lineage(-) bone marrow cells from C57/Bl6 mice revealed a broad transcriptional similarity between the sexes. However, we identified distinct sex differences in key biological pathways, with female cells showing reduced expression of signatures involved in inflammation and enrichment of genes related to glycolysis, hypoxia, and cell cycle regulation, suggesting a more quiescent and less inflammatory profile compared with male cells. To determine the functional impacts of the observed transcriptomic differences, we performed sex-matched and mismatched transplantation studies of lineage(-) donor cells. During short-term 56-day HST recovery, we found a male donor cell proliferative advantage, coinciding with elevated serum TNF-α, and a male recipient engraftment advantage, coinciding with increased serum CXCL12. Together, we show that sex-specific cell responses, marked by differing expression of pathways regulating metabolism, hypoxia, and inflammation, shape normal and regenerative hematopoiesis, with implications for the clinical understanding of hematopoietic function.
Despite numerous available psoriasis treatments, no "one size fits all" regimen provides complete disease control without side effects, logistical obstacles, and/or expense. Despite increasingly efficacious drugs, only 20-25% of patients treated with biologic therapies achieve completely clear skin (PASI 100) and even fewer achieve this if they have experienced failures of multiple biologics.
Aging people living with HIV (PWH) frequently manifest impaired antibody (Ab) responses to seasonal flu vaccination which has been attributed to ongoing inflammation and immune activation. We have recently reported a similar scenario in old simian immunodeficiency virus (SIV) infected rhesus macaques (RM) with controlled viremia and have been able to compensate for this deficiency by immunotherapy with interleukin (IL)-21-IgFc. To understand the underlying mechanisms of IL-21-induced immunomodulation leading to enhanced flu vaccine response in aging and SIV, we have investigated draining lymph node (LN) cells of IL-21-treated and -untreated animals at postvaccination. We observed IL-21-induced proliferation of flu-specific LN memory CD4 T cells, expansion of B cells expressing IL-21 receptor (IL-21R), and modest expansion of T follicular helper cells (Tfh) co-expressing T-cell immunoreceptor with Ig and ITIM domains (TIGIT) and DNAX accessory molecule (DNAM-1). Transcriptional analysis of LN cells of IL-21-treated animals revealed significant inhibition of germinal center (GC) Tfh and B-cell interferon signaling pathways along with enhanced B-cell development and antigen presentation pathways. We conclude that IL-21 treatment at the time of flu vaccination in aging SIV-infected animals modulates the inductive LN GC activity, to reverse SIV-associated LN Tfh and B-cell dysfunction. IL-21 is a potential candidate molecule for immunotherapy to enhance flu vaccine responses in aging PWH who have deficient antibody responses.
Human immunodeficiency virus 1 (HIV-1) exposed seronegative (HESN) individuals may have unique characteristics that alter susceptibility to HIV-1 infection. However, identifying truly exposed HESN is challenging. We utilized stored data and biospecimens from HIV-1 serodifferent couple cohorts, in which couples' HIV-1 exposures were quantified based on unprotected sex frequency and viral load of the partner with HIV-1. We compared peripheral blood gene expression between 15 HESN and 18 seroconverters prior to infection. We found PTPRC (encoding CD45 antigen) and interferon-response pathways had significantly higher expression among individuals who went on to become seropositive and thus may be a signature for increased acquisition risk.
Chronic immune activation during HIV-1 infection contributes to morbidity and mortality in people living with HIV. To elucidate the underlying biological pathways, we evaluated whole blood gene expression trajectories from before, through acute, and into chronic HIV-1 infection. Interferon-stimulated genes, including MX1, IFI27 and ISG15, were upregulated during acute infection, remained elevated into chronic infection, and were strongly correlated with plasma HIV-1 RNA as well as TNF-α and CXCL10 cytokine levels. In contrast, genes involved in cellular immune responses, such as CD8A, were upregulated during acute infection before reaching a peak and returning to near pre-infection levels in chronic infection. Our results indicate that chronic immune activation during HIV-1 infection is characterized by persistent elevation of a narrow set of interferon-stimulated genes and innate cytokines. These findings raise the prospect of devising a targeted intervention to restore healthy immune homeostasis in people living with HIV-1.