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Background: Peripheral arterial disease (PAD) is a manifestation of systemic atherosclerosis characterized by chronic inflammation and immune dysregulation. Single-cell RNA sequencing (scRNA-seq) studies of human atherosclerotic plaques have identified distinct transcriptional programs within plaque-associated immune cells. We sought to determine whether transcriptional features described within these plaque-resident cells can be identified in peripheral blood mononuclear cells (PBMCs). Methods: PBMCs from patients with PAD (n = 4) and healthy controls (HC) (n = 5) were profiled using scRNA-seq using the Parse Biosciences platform, yielding approximately 135,000 high-quality cells. Data analysis was conducted in R, using Seurat for quality control, dimensionality reduction and clustering. Cell-type annotation was performed using Azimuth reference-based mapping. Plaque-associated inflammatory and metabolic gene programs were curated from published human plaque single-cell atlases. Results: Gene expression differences between HC and PAD cells were visualized using UMAP plots. CD14+ mononuclear phagocytes (MNPs) exhibited the most prominent and consistent transcriptional differences between HC and PAD samples (Figure 1). Within CD14+ MNPs, genes involved in lipid handling and macrophage metabolic function demonstrated a higher median percentage of expressing cells in PAD compared with HC (Figure 2). Further analysis of AQP9 and CD36, genes implicated in macrophage metabolic activation and lipid uptake in atherosclerotic plaques, with z-score normalization and subject-level averaging revealed modest but consistent increases in relative expression in PAD across subjects. These findings support the relevance of these circulating transcriptional shifts to PAD pathophysiology. Conclusions: Circulating CD14+ MNPs in PAD have detectable transcriptional features consistent with potential engagement of plaque-associated myeloid activation programs. In PAD, increased expression of CD36, which encodes the immune cell scavenger receptor for oxidized LDL, and AQP9, associated with unstable plaques and the endothelial-to-mesenchymal transition, suggest altered immunometabolism states in circulating MNPs. Although effect sizes are modest, they are consistent across subjects and statistically robust. These findings highlight PBMC scRNA-seq as a minimally invasive approach to interrogate systemic immune programs relevant to PAD pathobiology.

Introduction: Co-stimulatory proteins are master regulators of the immune system. We identified the co-stimulatory CD40-CD40L dyad as a key driver of inflammation during atherosclerosis and have shown that CD40 and CD40L exert cell-type divergent functions. Hypothesis: CD40 is abundantly expressed on endothelial cells (EC) undergoing endothelial mesenchymal transition (EndMT). We hypothesize that EC CD40 drives atherosclerosis via EndMT. Methods: We analyzed scRNAseq data from human carotid plaques, performed multiplex IHC, and used human aortic endothelial cells (HAECs) for in vitro studies. A tamoxifen-inducible EC specific CD40 deficient atherosclerotic mouse model (cadherin5 (cdh5)ERT2-CD40 flfl -ApoE -/- ) was generated. Results: Besides its presence on immune cells, CD40 is expressed on endothelial cells in both human and mouse atherosclerotic plaques. Analysis of scRNAseq data of human carotid atherosclerotic plaques showed that CD40 is highly expressed in COL1A2/FN1 expressing endothelial cells (ECs), a subset undergoing EndMT. Multiplex staining revealed that CD40 colocalized with the EndMT markers αSMA, NOTCH3, TWIST and VCAM1 in human plaques. In vitro , stimulation of human arterial endothelial cells (HAECs) with CD40L resulted in an increase in the EndMT markers markers fibronectin, vimentin, sm22α, FSP1 and snail. Using phosphoproteomics, CD40L was found to decrease phosphorylation of the junctional integrity proteins CTNNA1 [S652; S655] and ARHGAP21 [S1383]. To investigate the endothelial-specific effects of CD40 in atherosclerosis, 8-week-old cdh5ERT2-CD40 flfl -ApoE -/- mice and their CD40 flfl -ApoE -/- littermate controls were treated with tamoxifen and fed a high cholesterol diet for 10 wks. Deletion of EC-CD40 resulted in a significant reduction in plaque size. This reduction was accompanied by a shift from fibrous cap atheromas (FCA) towards intimal xanthoma (IX) and pathological intimal thickening (PIT). Flow cytometry analysis of the spleen showed that CD40 deletion in ECs results in a significant decrease in CD8 and CD4 effector T cells. This decrease in CD8 and CD4 effector T cells was accompanied by a diminished activation status, shown by a decrease in CD69 + CD8 + CD62 - CD44 + T cells, CD40L + CD8 + CD62 - CD44 + T cells and CD40L + CD4 + CD62 - CD44 + T cells. These findings demonstrate that endothelial CD40 drives atherosclerosis by inducing EndMT-driven plaque inflammation.

Background: Increased arterial stiffness, a marker of cardiovascular disease (CVD), is prevalent among African American (AA) adults and contributes to persistent CVD disparities. The Cardio-Ankle Vascular Index (CAVI) is a validated measure of arterial stiffness and predictor of adverse CVD outcomes. However, its relationship with the novel American Heart Association’s Life’s Essential 8 (LE8) cardiovascular health (CVH) construct has not been examined among AAs. Hypothesis: We hypothesized that increased arterial stiffness would be associated with lower CVH among AA adults. Methods: We analyzed baseline data from AA adults in the Techquity by FAITH! Trial, a 2-arm cluster randomized controlled trial conducted across 18 AA churches in Rochester and Minneapolis–St. Paul, Minnesota. Eligible participants (age ≥18 years with suboptimal diet or physical activity [PA]) completed validated electronic surveys (e.g., PA patterns) and clinical assessments (e.g., blood pressure [BP], lipids). CAVI was summarized as mean and categorized as normal (<8), borderline (8 to <9), or abnormal (≥9). CVH was assessed using the LE8 score (range 0-100 points) and categorized as low (<50), moderate (50-79), or high (≥80). Associations between CAVI and LE8 were assessed using multivariable linear regression adjusted for age, sex, and income (continuous) and Fisher’s exact test (categorical). LE8 components were compared across CAVI categories using Kruskal–Wallis tests. Results: Among 140 participants (mean age 53.0 years [SD 14.6]; 68% female), the mean LE8 score was 62.7 (SD 14.0). Nicotine exposure LE8 score was the highest (84.6 [SD 26.6]) and diet was the lowest (40.7 [SD 13.7]). Mean CAVI was 7.9 (SD 1.5), with 50% of participants classified as normal, 22% borderline, and 28% abnormal. No association between continuous CAVI and LE8 scores was observed after adjustment (unadjusted R 2 = 3.5%). All participants with high LE8 had normal CAVI, while abnormal CAVI was more prevalent among those with low (40%) and moderate (30%) LE8 scores (p<0.001). LE8 scores differed across CAVI categories for BP (median 50 in normal CAVI vs 30 in borderline/abnormal CAVI; p=0.003) and glucose LE8 scores (median 100 vs 60; p=0.014). Conclusions: Greater arterial stiffness was associated with lower CVH categories, with notable component-level differences in BP and glucose. Although not independently associated with overall LE8, integrating CAVI and LE8 categories may improve CVD risk stratification among AAs.

Introduction: V-domain Immunoglobulin Suppressor of T-cell Activation (VISTA), a co-inhibitory immune checkpoint protein, is known for regulating adaptive immune responses. Here, we investigated the role of VISTA in atherosclerosis. Hypothesis: VISTA is constitutively expressed on hematopoietic cells, particularly T cells. VISTA functions as both a ligand and receptor to maintain T cell quiescence. We hypothesize that VISTA expression is protective against plaque formation by inhibiting CD4 + T cell activation. Methods: Cellular indexing of transcriptomes and epitopes by sequencing (CITE-seq) was performed on aortic CD45 + cells of HCD fed ApoE-/- mice. Spatial transcriptomics (VISIUM) was performed on carotid plaques from patients with either asymptomatic or symptomatic cerebrovascular disease. Plaque burden, characterization, and flow cytometry of blood and lymphoid organs were performed on VISTA -/- ApoE -/- (VISTA KO) and VISTA +/+ ApoE -/- (WT) mice that were fed a HCD for 10 weeks. ApoE -/- mice treated with VISTA agonist 8G8 or IgG control (200ug, intra-peritoneal, 3 times per week for the last 6/10 weeks of HCD feeding). In vitro proliferation, migration, and functional T cell assays were performed. Results: We found that VISTA is expressed on plaque T cell populations, particularly regulatory T cells, gamma-delta T cells, and naïve T cells. In humans, individuals with symptomatic CVD have significantly reduced VISTA gene expression in carotid plaques. VISTA KO mice have increased total plaque area and necrotic core area compared to littermate WT controls. VISTA KO mice have increased peripheral CD4 + and CD8 + effector memory T (T EM ) cells with a corresponding decrease in CD4 + and CD8 + naïve T (T N ) cells and CD4 + regulatory T (T reg ) cells. Further, VISTA KO mice have a higher frequency of CD4 + T H 1 (T-bet + IFNy + ) cells and lower frequencies of IL-10 + CD4 + T cells and CD4 + T H 2 (GATA-3 + IL-13 + ) cells. In vitro assays showed that VISTA suppresses CD4 + T cell proliferation, IFNγ production, and migration. Finally, VISTA agonist treatment significantly decreased plaque and necrotic core areas in atherosclerotic mice. Conclusion: Our data reveals a novel role for VISTA in reducing plaque development and in suppressing T cell activation, proliferation, and migration. Further characterization of T-cell specific VISTA-deficient mouse models and mechanistic insights into how VISTA modulates T cells are currently being investigated.

Background: Alterations in cardiovascular function are key features of severe acute pancreatitis (AP) and contribute substantially to mortality. Although sex differences in cardiovascular diseases are well recognized, with males generally exhibiting higher risk and poorer outcomes, their influence on AP-associated cardiovascular responses remains poorly defined. Therefore, we hypothesized that cerulein-induced AP causes severity-dependent and sex-specific changes in vascular integrity and cardiac function. Methods: Obesity has been associated with more severe forms of AP. Thus, mild and severe AP were induced by cerulein injections (100µg/kg/h×12) in lean (n=10 males, n=13 females) and obese (n=9 males, n=12 females) C57BL/6J mice, respectively. Vascular permeability was assessed by FITC-dextran extravasation. Cardiac function was assessed by echocardiography before and after cerulein injection. Cytokines were measured with multi-plex cytokine array and the role of angiopoietin-2 (Angpt2), an endothelial-derived regulator of vascular and cardiac responses, was evaluated using a neutralizing antibody. Results: Vascular permeability did not differ significantly between sexes in either AP model. In mild AP, males and females showed comparable increases in systolic function; however, in severe AP, only female mice maintained this adaptive systolic augmentation, assessed by fractional shortening (FS; 25.78±0.27% at baseline vs. 43.44±0.57% at endpoint, n=12, p<0.0001). This impaired cardiac adaptation in males was accompanied by increased myocardial inflammatory cytokines and elevated circulating free fatty acids. Among ten circulating cytokines measured, Angpt2 levels were significantly higher in males than females (male: 63.50±1.52ng/mL, n=9 vs. female: 41.37±2.68ng/mL, n=6, p=0.013) and were negatively correlated with systolic performance (FS; R 2 =0.75, p<0.0001), while positively associated with preload (end-diastolic volume; R 2 =0.55, p=0.0015). Unexpectedly, Angpt2 neutralization did not improve the cardiac adaptations in males and instead worsened cardiac performance as reflected by reduced FS (control IgG: 32.83±1.47%, n=4 vs. Anti-Angpt2: 22.88±0.64%, n=5, p=0.013) in severe AP. Conclusions: AP elicits both sex-dependent and sex-independent cardiovascular responses, with female mice exhibiting preserved cardiac adaptation, and Angpt2 is a potential compensatory mediator of cardiac protection in severe AP.

Introduction: Atherosclerotic lesions preferentially form in arterial regions exposed to disturbed flow (DF), where ECs exhibit mitochondrial (mt) dysfunction, metabolic reprogramming, and senescence. Hippo pathway kinases LATS1/2 maintain EC homeostasis, but how DF–mediated LATS1/2 suppression drives EC metabolic remodeling remains unclear. Hypothesis: We propose that DF activates CD38, leading to mt dysfunction and metabolic reprogramming that promotes EC senescence and aberrant proliferation by LATS1/2 inhibition. Methods: EC-specific Lats1/2 knockout mice were generated using tamoxifen-inducible Cre systems, and DF was induced by partial carotid ligation. Murine and human plaques were analyzed using COMET™ immunofluorescence, and spatial metabolomics. Bioenergetic profiling included Seahorse XF analysis, 13 C-glucose/ 13 C-glutamine tracing, and pharmacologic modulation of CD38, mtROS, and ATP synthase. Results: Complete Lats1/2 deletion caused fatal edema and vascular leakage, while partial loss produced fragile, highly neovascularized plaques. Spatial proteomics revealed a CD38-driven senescence-associated stemness (SAS) phenotype under LATS1/2 deficiency. Metabolomics showed sulfite and taurine accumulation, consistent with SUOX deficiency. Mechanistically, CD38 suppressed SUOX, induced Complex V reverse-mode , increased succinate flux, and accelerated ATP consumption. Despite ATP depletion, glutamate metabolism and TCA cycle flux were enhanced, sustaining EC proliferation under energetic stress. LATS1/2 knockdown reduced mt respiratory capacity (lower OCR peak) without significantly increasing glycolysis, and DF suppressed both OCR and ECAR, indicating impaired energy metabolism under pathological shear stress. CD38 inhibition restored mt respiration and glycolytic capacity by preserving NAD, and rescuing LATS1/2 and DF-mediated defects. Blocking reverse-mode Complex V reduced DF- and LATS1/2-dependent EC senescence and proliferation. Conclusion: Complete LATS1/2 deletion causes fatal vascular leakage, while partial loss drives plaque formation with fragile neovessels through a CD38-dependent SAS phenotype. CD38 suppresses SUOX, induces Complex V reverse-mode , increases succinate flux, and accelerates ATP consumption, enabling EC proliferation despite energy stress. DF and LATS1/2 loss impair mt and glycolytic function, whereas CD38 inhibition restores mt respiration and reduces EC senescence and proliferation to prevent atherothrombosis in DF regions.

Background Hearing impairment (HI) has been identified as a potentially modifiable risk factor for dementia, yet its relationship with Alzheimer's disease (AD) neuropathology and the temporal directionality remain unclear, particularly in late life. Objective To examine cross-sectional and longitudinal associations between HI, clinical cognitive status, and AD biomarkers in community-dwelling older adults. Methods We included 474 DRIVES Project participants (mean age 73.5 ± 5.2 years). Hearing was assessed using the NIH Toolbox Words-in-Noise (WIN) test. Clinical cognitive status was assessed using Clinical Dementia Rating (CDR). AD biomarkers included cerebrospinal fluid (CSF) Aβ 42 /Aβ 40 , t-tau/Aβ 42 , and p-tau/Aβ 42 ratios and amyloid PET imaging. Multivariable linear, logistic, Cox proportional hazards, and Fine–Gray competing-risk models were used. Results HI was more prevalent among participants with mild cognitive impairment (MCI; defined as CDR = 0.5) than cognitively normal individuals (50% versus 24%, p < 0.001), and MCI status was independently associated with worse baseline WIN thresholds (β = 1.55 dB SNR; 95% CI 0.72–2.37). HI was not cross-sectionally associated with CSF amyloid or tau ratios or amyloid PET positivity. Longitudinally, baseline MCI was associated with a higher risk of incident HI (Cox HR = 2.63, 95% CI 1.48–4.67; Fine–Gray sHR = 2.79, 95% CI 1.06–7.40), whereas baseline HI was not associated with subsequent CDR progression. Conclusions In older adults, HI was associated with MCI but not core AD biomarkers or future CDR progression, suggesting that late-life HI may reflect cognitive vulnerability or broader brain aging rather than independently driving AD pathology.

Treatment of participants with intermediate-risk prostate cancer with focal irreversible electroporation and radiation therapy was technically feasible and showed acceptable patient-reported outcomes and no severe adverse events over 1 year.

Primary sternal osteomyelitis (PSO) is an exceptionally rare infection of the sternum, typically occurring in the context of trauma, surgery or immunocompromise. We report the case of a previously healthy adolescent boy in his second decade of life presenting with fever, chest pain and localised tenderness without any identifiable risk factors. Initial workup, including a chest X-ray and echocardiogram, was unremarkable, but persistent bacteraemia with methicillin-sensitive Staphylococcus aureus prompted further imaging. MRI revealed sternal osteomyelitis with a small parasternal abscess. The patient was successfully treated with intravenous antibiotics alone, avoiding surgical intervention. This case highlights the importance of thorough physical examination and maintaining a high index of suspicion for PSO in patients with unexplained fever and chest wall tenderness, even in the absence of traditional risk factors. Early diagnosis and targeted therapy are essential to optimise outcomes in this rare condition.