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Descending thoracic aortic aneurysms may go undetected until severe and catastrophic complications such as rupture or dissection occur. Few clinical indicators exist to screen for aneurysms or predict risk of dissection or rupture. This study generated a plasma proteomic dataset from 150 patients with descending thoracic aortic disease and 52 controls to identify proteomic signatures capable of differentiating descending thoracic aortic disease from controls, as well as aneurysm from descending aortic dissections. Of the 1,468 peptides and 195 proteins quantified, 853 peptides and 99 proteins were significantly different between disease and controls. Using machine learning to classify disease from control, the highest precision-recall area under the curve (PR AUC) was achieved using significantly different proteins (PR AUC 0.99), followed by significant peptides (PR AUC 0.96). Despite no statistically significant protein signatures between aneurysm and dissection, use of all proteins was able to modestly classify between the disease states (PR AUC 0.77). To address correlation between proteins, a disease versus control classifier was optimized using only seven unique protein clusters, which achieved comparable performance to models trained on all/significant proteins (PR AUC 0.90). Model interpretation with permutation importance revealed that proteins differentiating disease and control function in coagulation, protein-lipid complex remodeling, and acute inflammatory response.

Immune responses activated by LDL particles that have been trapped and oxidized in the arterial wall play an important role in atherosclerosis. Some of these immune responses are protective by facilitating the removal of pro-inflammatory and toxic lipid species formed as result of LDL oxidation. However, should these protective immune responses be insufficient, other more potent pro-inflammatory immune responses instead contributing to disease progression will gradually become dominant. The importance of the balance between protective and pathogenic immunity is particularly apparent when it comes to the adaptive immune system where pro-inflammatory T helper 1 (Th1) type T cells aggravate atherosclerosis, while regulatory T cells (Tregs) have an opposing role. As oxidized LDL is a key autoantigen in atherosclerosis, it has become an interesting possibility that immune-modulatory therapy that favors the activity of apolipoprotein B peptide-specific Tregs could be developed into a novel treatment strategy for prevention/stabilization of atherosclerosis and ischemic cardiovascular events. Indeed, several such oxidized LDL tolerance vaccines have shown promising results in animal models of atherosclerosis. This review will discuss the experimental background for development of atherosclerosis vaccines based on LDL-derived antigens as well as the challenges involved in translating these findings into clinical application.

Introduction: The increased consumption of dietary fat has been well established to lead to cardiovascular disease via the elevation of lipids in serum. High blood pressure is also commonly associated with high serum cholesterol levels, but the relationships among blood pressure, dietary sodium intake and serum cholesterol have not been fully elucidated. Hypothesis: An increase in the intake of salt causes an elevation of serum cholesterol through the activation of hepatic enzymes critical to cholesterol synthesis. Methods: Dahl salt-sensitive rats (n=6) were fed a high-salt (HS) diet (8% NaCl) from 7 weeks of age to induce hypertension. Rats fed a normal-salt (NS) diet (0.3% NaCl; n=6) served as controls. Blood pressure was measured non-invasively using a tail artery cuff. Blood was withdrawn from 6-hour fasting HS and NS-fed rats to check serum cholesterol levels. Low-density lipoprotein (LDL), high-density lipoprotein (HDL), and very-low density lipoprotein (VLDL) cholesterols were measured. Gene expression array and western blot were performed in liver protein extracts from HS and NS-fed rats. Results: Systolic blood pressure was elevated in HS-fed rats compared to NS-fed rats at 16 weeks of age (225±23 vs. 156±18 mmHg, p=0.0002). Serum fasting cholesterol was higher in hypertensive rats compared to normotensive rats (194±49 vs. 102±12 mg/dL, p=0.0013). LDL cholesterol was higher in HS-fed rats compared to NS-fed rats (83±9 vs. 60±10 mg/dL, p=0.0024), while HDL and VLDL cholesterol were not. Hepatic cholesterol synthesis gene array revealed significant up-regulation of 3 genes in hypertensive rats in comparison to normotensive rats ( Apoa1 fold change [FC] 2.84, pTm7sf2 FC 2.45, p=0.0004; Cyp51 FC 2.44, p=0.0002). Western blot of hepatic protein extracts showed a definitive increase in CYP51 in HS-fed rats compared to NS-fed rats (normalized against GAPDH, 2.7-fold increase, p=0.0018). Conclusions: A high-salt diet increased serum cholesterol levels, potentially via activation of liver enzyme CYP51, which is crucial for the synthesis of cholesterol in the liver. Further research is warranted to investigate the mechanisms of how high-salt diets can increase CYP51 in the liver.

Epicardial adipose tissue has a paracrine effect, enhancing coronary artery atherosclerotic plaque development. This study evaluated epicardial fat volume (EFV), adipokines, coronary atherosclerosis, and adverse cardiovascular events in a cohort of asymptomatic patients with type 2 diabetes mellitus (T2DM). Epicardial fat volume was calculated using data from computed tomography coronary angiograms. Adipokines and inflammatory cytokines were also assayed and correlated with EFV. Epicardial fat volume was also assessed as a predictor of coronary artery calcium (CAC) score, number of coronary artery plaques, and significant plaque (>50% luminal stenosis). Data from the EFV analysis were available for 221 (85.7%) participants. Median EFV was 97.4 cm3, mean body mass index was 28.1 kg/m2, and mean duration of T2DM was 13 years. Statistically significant, but weak, correlations were observed between several adipokines, inflammatory cytokines, and EFV. Epicardial fat volume was a significant univariate ( P = .01), but not multivariate, predictor of the number of coronary plaques, but not of CAC score or significant plaque. After a mean follow-up of 22.8 months, 12 adverse cardiovascular events were reported, exclusively in participants with EFV >97.4 cm3. Epicardial fat volume has limited utility as a marker of coronary artery plaque in patients with T2DM and is weakly correlated with adipokine expression.

Background High-density lipoprotein cholesterol (HDL-C) concentration is inversely related to risk of major adverse cardiovascular events (MACE) in epidemiologic studies but is a poorer predictor of MACE in patients with established coronary heart disease. HDL particle concentration (HDLP) has been proposed as a better predictor of risk. We investigated whether HDLP is associated with risk of MACE after acute coronary syndrome (ACS). Methods The dal-Outcomes trial compared the CETP inhibitor dalcetrapib with placebo in patients with recent ACS. In a nested case-cohort analysis, total, large, medium, and small HDLPs were measured by nuclear magnetic resonance spectroscopy at baseline (4-12 weeks after ACS) in 476 cases with MACE and 902 controls. Hazard ratios (HRs; case-control) for 1-SD increment of HDLP or HDL-C at baseline were calculated with and without adjustment for demographic, clinical, laboratory, and treatment variables. Similarly, HRs for MACE were calculated for changes in HDLP or HDL-C from baseline to month 3 of assigned treatment. Results Over median follow-up of 28 months, the risk of MACE was not associated with baseline HDLP (adjusted HR = 0.98, 95% CI = 0.84-1.15, P = .81), any HDLP subclass, or HDL-C. Dalcetrapib increased HDL-C and total, medium, and large HDLP and decreased small HDLP but had no effect on MACE compared with placebo. There were no association of risk of MACE with change in HDLP or HDL-C and no interaction with assigned study treatment. Conclusions Neither baseline HDLP nor the change in HDLP on treatment with dalcetrapib or placebo was associated with risk of MACE after ACS.

Background: The use of nanoparticles for efficient delivery of therapeutic modalities in humans is rapidly increasing. We have previously reported that a nanovaccine consisting of apoB-100 peptide P210 complexed with amphiphilic micelles (P210-PAM) significantly reduces atherosclerosis in apoE-/- mice. In this study, we defined the mechanistic pathway for the atheroprotective effect of P210-PAM. Methods and Results: Seven-week male apoE-/- mice were immunized with P210-PAM or mouse serum albumin peptide amphiphile micelles (MSA-PAM) at a dose of 100ug per injection at 7, 10, and 12 weeks of age. One week after the second booster, mice were euthanized and the splenocytes were collected for immune profiling and immune assays. A second group of immunized mice were injected with thioglycolate to elicit peritoneal macrophages. Splenocytes from P210-PAM mice collected 1 week after the second booster had significantly increased CD4+CD25+FoxP3+ Treg cells and CD8+CTLA-4+ T cells compared to MSA-PAM mice (N=9 each; P≤0.05). Splenocytes from P210-PAM mice had reduced CD4+ T cell proliferation and CD8+CD107a+ T cells in response to P210 recall compared to MSA-PAM (N=8 and 9, respectively; P Conclusion: The mechanism of the protective effect of P210-PAM nanoparticles in reducing the immune-inflammatory response in atherosclerosis is at the level of both adaptive T cell response as well as innate macrophage response. The use of P210-PAM in future investigations as potential clinical therapy for atherosclerosis is thus warranted.

Background: Antibodies to the apoB-100 peptide P210 have been reported in coronary artery disease (CAD) patients yet the nature of intrinsic self-reactive T cell response in these patients remains to be investigated. Given the reported presence of antibodies to P210 in CAD, we hypothesized that the P210 peptide would provoke T cell activation in peripheral blood mononuclear cells (PBMCs) of acute coronary syndrome (ACS) patients and would manifest as T Effector/Memory cells, previously demonstrated to correlate with atherosclerotic disease. Methods and Results: PBMCs from ACS patients were collected under an approved IRB and kept viable in cryo-preservation until assays. Cryo-preserved viable PBMCs from self-reported controls were purchased from a commercial vendor with their own IRB. T cell activation was assessed by stimulating PBMCs in vitro for 16 hours with P210 peptide. Negative control was no treatment and positive controls were stimulation with pooled CMV peptides or PMA/ionomycin cocktail. The Activation Induced Marker (AIM) flow cytometric assay was performed with the following antibodies: CD4, CD8, CD25, CD69, CD134, CD137, and CD154 using non-viable cells and CD14, CD16 and CD19 as dump gates. AIM+ cells were expressed as the ratio relative to no stimulation. T Effector/Memory responses were assessed after 72 hours of stimulation with P210. Negative control was no stimulation and positive control was stimulation with PMA/ionomycin. Viable T Effector/Memory cells were identified as positive for CD3, CD4, CD8, and CD45RO, but CD45RA(-), CD62L(-) and CCR7(-) by flow cytometry. T Effector/Memory cells were expressed as Response Index (negative control subtracted from P210 stimulation divided by the positive control for each sample). P210 stimulation significantly increased CD4+CD69+CD134+ (AIM+) cells in ACS (P Conclusion: P210 provokes self-reactive T cell activation and Effector/Memory responses in ACS patients consistent with the immunogenic role of P210 in coronary artery disease pathophysiology.

Background Eukaryotic cells can respond to diverse stimuli by converging at serine-51 phosphorylation on eukaryotic initiation factor 2 alpha (eIF2α) and activate the integrated stress response (ISR). This is a key step in translational control and must be tightly regulated; however, persistent eIF2α phosphorylation is observed in mouse and human atheroma. Objectives Potent ISR inhibitors that modulate neurodegenerative disorders have been identified. Here, the authors evaluated the potential benefits of intercepting ISR in a chronic metabolic and inflammatory disease, atherosclerosis. Methods The authors investigated ISR’s role in lipid-induced inflammasome activation and atherogenesis by taking advantage of 3 different small molecules and the ATP-analog sensitive kinase allele technology to intercept ISR at multiple molecular nodes. Results The results show lipid-activated eIF2α signaling induces a mitochondrial protease, Lon protease 1 (LONP1), that degrades phosphatase and tensin-induced putative kinase 1 and blocks Parkin-mediated mitophagy, resulting in greater mitochondrial oxidative stress, inflammasome activation, and interleukin-1β secretion in macrophages. Furthermore, ISR inhibitors suppress hyperlipidemia-induced inflammasome activation and inflammation, and reduce atherosclerosis. Conclusions These results reveal endoplasmic reticulum controls mitochondrial clearance by activating eIF2α-LONP1 signaling, contributing to an amplified oxidative stress response that triggers robust inflammasome activation and interleukin-1β secretion by dietary fats. These findings underscore the intricate exchange of information and coordination of both organelles’ responses to lipids is important for metabolic health. Modulation of ISR to alleviate organelle stress can prevent inflammasome activation by dietary fats and may be a strategy to reduce lipid-induced inflammation and atherosclerosis., Central Illustration

Reperfusion therapy for acute myocardial infarction (MI) is lifesaving. However, the benefit of reperfusion therapy can be paradoxically diminished by reperfusion injury, which can increase MI size.Hemorrhage is known to occur in reperfused MIs, but whether hemorrhage plays a role in reperfusion-mediated MI expansion is not known.We studied cardiac troponin kinetics (cTn) of ST-segment elevation MI patients (n = 70) classified by cardiovascular magnetic resonance to be hemorrhagic (70%) or nonhemorrhagic following primary percutaneous coronary intervention. To isolate the effects of hemorrhage from ischemic burden, we performed controlled canine studies (n = 25), and serially followed both cTn and MI size with time-lapse imaging.CTn was not different before reperfusion; however, an increase in cTn following primary percutaneous coronary intervention peaked earlier (12 hours vs 24 hours; P 0.05) and was significantly higher in patients with hemorrhage (P 0.01). In hemorrhagic animals, reperfusion led to rapid expansion of myocardial necrosis culminating in epicardial involvement, which was not present in nonhemorrhagic cases (P 0.001). MI size and salvage were not different at 1 hour postreperfusion in animals with and without hemorrhage (P = 0.65). However, within 72 hours of reperfusion, a 4-fold greater loss in salvageable myocardium was evident in hemorrhagic MIs (P 0.001). This paralleled observations in patients with larger MIs occurring in hemorrhagic cases (P 0.01).Myocardial hemorrhage is a determinant of MI size. It drives MI expansion after reperfusion and compromises myocardial salvage. This introduces a clinical role of hemorrhage in acute care management, risk assessment, and future therapeutics.

After HSV-1 infection, macrophages infiltrate early into the cornea, where they play an important role in HSV-1 infection. Macrophages are divided into M1 or M2 groups based on their activation. M1 macrophages are pro-inflammatory, while M2 macrophages are anti-inflammatory. Macrophage phenotypes can shift between M1 or M2 in vitro and in vivo following treatment with specific cytokines. In this study we looked at the effect of M2 macrophages on HSV-1 infectivity using mice either lacking M2 (M2-/-) or overexpressing M2 (M2-OE) macrophages. While presence or absence of M2 macrophages had no effect on eye disease, we found that over expression of M2 macrophages was associated with increased phagocytosis, increased primary virus replication, increased latency, and increased expression of pro- and anti-inflammatory cytokines. In contrast, in mice lacking M2 macrophages following infection phagocytosis, replication, latency, and cytokine expression were similar to wild type mice. Our results suggest that enhanced M2 responses lead to higher phagocytosis, which affected both primary and latent infection but not reactivation., Author summary Macrophages are one of the major infiltrates into the cornea of ocularly infected mice and may contribute to both disease and protection. Similar to TH1/TH2 T cells, macrophages also are divided into M1/M2 subtypes. However, very little is known about the role, if any, that M1/M2 macrophages play in HSV-1 primary and latent infection. Here we investigated the role of M1/M2 macrophages in HSV-1 latency-reactivation by generating M2-/- mice as well as conditional transgenic mice that overexpress M2 macrophages. We found that higher expression of M2 macrophages correlated with higher phagocytosis, higher primary virus replication and latency, and higher IL-4 and IFN-γ expression, while the absence of M2 macrophages did not significantly alter HSV-1 infectivity compared with wild type mice. Thus, maintaining a balanced proportion of M1/M2 macrophage phenotype may be an effective way to control both primary and latent infection.

Atherosclerosis is a complex disease process with lipid as a traditional modifiable risk factor and therapeutic target in treating atherosclerotic cardiovascular disease (ACVD). Recent evidence indicates that genetic influence and host immune response also are vital in this process. How these elements interact and modify each other and if immune response may emerge as a novel modifiable target remain poorly understood. Numerous preclinical studies have clearly demonstrated that hypercholesterolemia is essential for atherogenesis, but genetic variations and host immune-inflammatory responses can modulate the pro-atherogenic effect of elevated LDL-C. Clinical studies also suggest that a similar paradigm may also be operational in atherogenesis in humans. More importantly each element modifies the biological behavior of the other two elements, forming a triangular relationship among the three. Modulating any one of them will have downstream impact on atherosclerosis. This brief review summarizes the relationship among lipids, genes, and immunity in atherogenesis and presents evidence to show how these elements affect each other. Modulation of immune response, though in its infancy, has a potential to emerge as a novel clinical strategy in treating ACVD.

The human cationic anti-microbial peptide LL-37 is a T cell self-antigen in patients with psoriasis, who have increased risk of cardiovascular events. However, the role of LL-37 as a T cell self-antigen in the context of atherosclerosis remains unclear. The objective of this study was to test for the presence of T cells reactive to LL-37 in patients with acute coronary syndrome (ACS). Furthermore, the role of T cells reactive to LL-37 in atherosclerosis was assessed using apoE−/− mice immunized with the LL-37 mouse ortholog, mCRAMP. Peripheral blood mononuclear cells (PBMCs) from patients with ACS were stimulated with LL-37. PBMCs from stable coronary artery disease (CAD) patients or self-reported subjects served as controls. T cell memory responses were analyzed with flow cytometry. Stimulation of PBMCs with LL-37 reduced CD8+ effector T cell responses in controls and patients with stable CAD but not in ACS and was associated with reduced programmed cell death protein 1 (PDCD1) mRNA expression. For the mouse studies, donor apoE−/− mice were immunized with mCRAMP or adjuvant as controls, then T cells were isolated and adoptively transferred into recipient apoE−/− mice fed a Western diet. Recipient mice were euthanized after 5 weeks. Whole aortas and hearts were collected for analysis of atherosclerotic plaques. Spleens were collected for flow cytometric and mRNA expression analysis. Adoptive transfer experiments in apoE−/− mice showed a 28% reduction in aortic plaque area in mCRAMP T cell recipient mice (P < 0.05). Fifty six percent of adjuvant T cell recipient mice showed calcification in atherosclerotic plaques, compared to none in the mCRAMP T cell recipient mice (Fisher’s exact test P = 0.003). Recipients of T cells from mice immunized with mCRAMP had increased IL-10 and IFN-γ expression in CD8+ T cells compared to controls. In conclusion, the persistence of CD8+ effector T cell response in PBMCs from patients with ACS stimulated with LL-37 suggests that LL-37-reactive T cells may be involved in the acute event. Furthermore, studies in apoE−/− mice suggest that T cells reactive to mCRAMP are functionally active in atherosclerosis and may be involved in modulating plaque calcification.

Despite growing evidence for the characteristic signs of Alzheimer's disease (AD) in the neurosensory retina, our understanding of retina–brain relationships, especially at advanced disease stages and in response to therapy, is lacking. In transgenic models of AD (APPSWE/PS1∆E9; ADtg mice), glatiramer acetate (GA) immunomodulation alleviates disease progression in pre‐ and early‐symptomatic disease stages. Here, we explored the link between retinal and cerebral AD‐related biomarkers, including response to GA immunization, in cohorts of old, late‐stage ADtg mice. This aged model is considered more clinically relevant to the age‐dependent disease. Levels of synaptotoxic amyloid β‐protein (Aβ)1–42, angiopathic Aβ1–40, non‐amyloidogenic Aβ1–38, and Aβ42/Aβ40 ratios tightly correlated between paired retinas derived from oculus sinister (OS) and oculus dexter (OD) eyes, and between left and right posterior brain hemispheres. We identified lateralization of Aβ burden, with one‐side dominance within paired retinal and brain tissues. Importantly, OS and OD retinal Aβ levels correlated with their cerebral counterparts, with stronger contralateral correlations and following GA immunization. Moreover, immunomodulation in old ADtg mice brought about reductions in cerebral vascular and parenchymal Aβ deposits, especially of large, dense‐core plaques, and alleviation of microgliosis and astrocytosis. Immunization further enhanced cerebral recruitment of peripheral myeloid cells and synaptic preservation. Mass spectrometry analysis identified new parallels in retino‐cerebral AD‐related pathology and response to GA immunization, including restoration of homeostatic glutamine synthetase expression. Overall, our results illustrate the viability of immunomodulation‐guided CNS repair in old AD model mice, while shedding light onto similar retino‐cerebral responses to intervention, providing incentives to explore retinal AD biomarkers., In this study, Doustar et al. revealed that retinal Abeta burden predicts its brain levels in old, late‐stage murine models of Alzheimer's disease and further in response to immunotherapy. Substantial therapeutic effects are detected even at such advanced disease stage; immunomodulation effectively mitigates vascular and parenchymal amyloid‐beta deposition, diminishes neuroinflammation, as well as restores synaptic density and retino‐cerebral glutamine synthetase levels.

Background Macrophages are highly plastic cells that play an important role in the pathogenesis of cardiovascular disease. Objectives This study investigated the role of GATA3-positive macrophages in modulating cardiac function after myocardial infarction (MI) or in response to pressure overload hypertrophy. Methods Myeloid-specific GATA3-deficient (mGATA3KO) mice were generated, MI or pressure overload was induced, and cardiac function was determined by echocardiography. GATA3-sufficient Cre mice were used as a control. Immunohistochemical staining, flow cytometry, MILLIPLEX Mouse Cytokine/Chemokine Assay, cultured macrophages, quantitative real-time polymerase chain reaction, and western blot were used to determine the role of GATA3 in macrophages. Results GATA3-positive macrophages rapidly accumulated in the infarcted region of the myocardium after acute MI. Deficiency of GATA3-positive macrophages led to a significant improvement of cardiac function in response to acute MI or pressure overload hypertrophy compared with the control mice. This improvement was associated with the presence of a large number of proinflammatory Ly6Chi monocytes/macrophages and fewer reparative Ly6Clo macrophages in the myocardium of mGATA3KO mice compared with control mice. Analysis of serum proteins from the 2 mouse genotypes revealed no major changes in the profile of serum growth factors and cytokines between the 2 mice genotypes before and after MI. GATA3 was found to be specifically and transiently induced by interleukin 4 in cultured macrophages through activity of the proximal promoter, whereas the distal promoter remained silent. In addition, the absence of GATA3 in macrophages markedly attenuated arginase-1 expression in cultured macrophages. Conclusions We demonstrated that the presence of GATA3-positive macrophages adversely affects remodeling of the myocardium in response to ischemia or pressure overload, whereas the absence of these macrophages led to a significant improvement in cardiac function. Targeting of signaling pathways that lead to the expression of GATA3 in macrophages may have favorable cardiac outcomes.

Background Recent studies indicate that Toll-like receptor 4 (TLR4) and myeloid differentiation factor 88 (MyD88) signaling promote the development of high fat diet–induced atherosclerosis in hypercholesterolemic mice. Objectives The authors investigated the role of TLR4/MyD88 signaling in hematopoietic and stromal cells in the development and infection-mediated acceleration of atherosclerosis. Methods The authors generated bone marrow chimeras between wild-type and Tlr4–/– mice, as well as wild-type and Myd88–/– mice. All mice were on the Apoe–/– background and fed high fat diet. The authors infected the chimeric mice with C. pneumoniae (CP) and fed them high fat diet. Results Aortic sinus plaques and lipid content were significantly reduced in Apoe–/– mice that received Tlr4–/–or Myd88–/– bone marrow compared with control animals despite similar cholesterol levels. Similarly, Tlr4 or Myd88 deficiency in stromal cells also led to a reduction in the lesion area and lipid in aortic sinus plaques. MyD88 expression only in CD11c+ dendritic cells (myeloid cells) in cells was sufficient in otherwise MyD88-deficient mice to induce CP infection–mediated acceleration of atherosclerosis, underlining the key role of MyD88 in CD11c+ dendritic cells (myeloid cells). Whereas CP infection markedly accelerated atherosclerosis in TLR4- or MyD88-positive chimeras, CP infection had a minimal effect on atherosclerosis in TLR4- or MyD88-deficient mice (either in the hematopoietic or stromal cell compartments). Conclusions The authors show that both CP infection and metabolic stress associated with dyslipidemia use the same innate immune response pathway, utilizing TLR4/MyD88 signaling, with similar relative contributions in bone marrow–derived hematopoietic cells and in stromal cells. Further studies are required to understand this intricate and complex cross talk among innate and adaptive immune systems in various conditions to more effectively design dendritic cell–mediated atheroprotective vaccines and other therapeutic strategies.

Patients with previous atherosclerotic cardiovascular disease (ASCVD) and/or heterozygous familial hypercholesterolemia (HeFH) are at high risk of future cardiovascular events. Despite maximally tolerated doses of statins, many patients still have elevated low-density lipoprotein cholesterol (LDL-C) levels. We evaluated the efficacy and safety of alirocumab in patients with ASCVD and/or HeFH on a maximally tolerated dose of statin (rosuvastatin 20 or 40 mg, atorvastatin 40 or 80 mg, or simvastatin 80 mg, or lower doses with an investigator-approved reason) ± other lipid-lowering therapies from 5 placebo-controlled phase 3 trials (52 to 78 weeks). Patients with (n = 2,449) and without (n = 1,050) ASCVD were pooled from the FH I, FH II, HIGH FH, LONG TERM, and COMBO I trials. Patients with HeFH with (n = 575) and without ASCVD (n = 682) were pooled from all trials except COMBO I. High-intensity statins were utilized in 55.7% to 59.0% and in 72.4% to 87.6% of the ASCVD and the HeFH groups, respectively. Efficacy end points included LDL-C percent change from baseline to week 24 stratified by alirocumab dose. Mean baseline demographics and lipid levels were comparable in alirocumab- and placebo-treated patients. LDL-C reductions from baseline at week 24 ranged from 46.6% to 51.3% for alirocumab 75/150 mg and from 54.1% to 61.9% for alirocumab 150 mg in ASCVD and HeFH groups and were sustained for up to 78 weeks. LDL-C reductions with alirocumab were independent of ASCVD and/or HeFH status (interaction p value >0.05). Concordant results were observed for other lipids analyzed. The overall safety in the subgroups analyzed was similar in both treatment arms. Injection-site reactions were observed more frequently with alirocumab versus placebo.

Background and aims Inflammation, particularly innate immunity, plays an important role in cardiovascular diseases. The aim of this study was to investigate whether atherogenic determinants such as oxidized LDL modulate the phenotype of eosinophils. Methods Cultured eosinophils were treated with oxidized LDL and the expression of selective inflammatory and anti-inflammatory cytokines was determined. In addition, the eosinophil receptor and signaling that mediate these events were identified. Results Treatment of cultured eosinophils with oxidized LDL (Ox-LDL) specifically induced the expression of IFNα and IFNβ without affecting expression of other proinflammatory cytokines, such as TNFα, IL-1β, and IL-6. In macrophages, Ox-LDL downregulated expression of both IFNα and IFNβ, suggesting that the effect of Ox-LDL on the expression of type I interferons is specific to eosinophils. Furthermore, we noted that eosinophils constitutively expressed IL-4 and IL-13, and Ox-LDL markedly downregulated their expression. Analysis of Ox-LDL signaling revealed that eosinophils constitutively expressed SRB2, CD36, and CD68 scavenger receptors, and Ox-LDL markedly induced the expression of CD36. Further analysis of CD36 signaling by siRNA and neutralizing antibodies showed that the induction of type I IFN by Ox-LDL is mediated by CD36 signaling whereas downregulation of IL-4 is independent of CD36 activation. We further showed that peritoneal macrophages treated with condition medium collected from Ox-LDL treated eosinophils markedly induced the expression of M1 markers such as iNOS, IL6, SOSC3 and TNFα whereas the condition medium from non-treated eosinophils significantly induced expression of M2 markers like ARG1 and CCL24. Conclusions Our data suggest that an atherogenic condition could activate eosinophils and modulate the phenotype of macrophages (from M2 to M1 phenotype), in part, through the CD36 receptor signaling.

Homozygous familial hypercholesterolemia is a genetic disorder characterized by low-density lipoprotein (LDL)-receptor dysfunction, markedly elevated levels of LDL-cholesterol (LDL-C) and premature atherosclerosis. Patients are often poorly responsive to conventional lipid-lowering therapies that upregulate LDL-receptor expression.1 Lomitapide inhibits microsomal triglyceride transfer protein, which lipidates nascent apolipoprotein (apo)B-containing lipoproteins. In a pivotal 78-week open-label trial, lomitapide, titrated to the maximal tolerable dose, decreased LDL-C by 50% at the end of the efficacy phase (week 26) in patients with homozygous familial hypercholesterolemia.2 The principal adverse events included gastrointestinal disturbances, hepatic enzyme elevations, and increased liver fat. Here we provide additional long-term efficacy and safety data, including an exploratory analysis of the potential metabolic consequences of hepatic fat accumulation from an extension trial (NCT00943306). Patients continued on lomitapide at the maximally tolerated dose until transition to commercial or compassionate lomitapide. Lipid-lowering therapies, including apheresis, could be modified at the investigator’s discretion if LDL-C was

Atherosclerosis is a chronic inflammatory disease. Pathophysiological similarities between chronic infections and atherosclerosis triggered interest in a clinical association between these conditions. Various infectious microbes have been linked to atherosclerotic vascular disease in epidemiological studies. However, this association failed to satisfy the Koch's postulates of causation with multiple clinical trials demonstrating inefficacy of anti-infective therapies in mitigating atherosclerotic cardiovascular events. Identification of underlying pathophysiological mechanisms and experience with vaccination against various infectious agents has ushered a new avenue of efforts in the development of an anti-atherosclerotic vaccine. Studies in animal models have identified various innate and adaptive immune pathways in atherosclerosis. In this review, we discuss the patho-biological link between chronic infections and atherosclerosis, evaluate existing evidence of animal and human trials on the association between infections and cardiovascular disease and introduce the concept of an anti-atherosclerotic vaccine.

Objectives The aim of this work is the development of coronary atherosclerosis T1-weighted characterization with integrated anatomical reference (CATCH) technique and the validation by comparison with high-risk plaque features (HRPF) observed on intracoronary optical coherence tomography (OCT) and invasive coronary angiography. Background T1-weighted cardiac magnetic resonance with or without contrast media has been used for characterizing coronary atherosclerosis showing promising prognostic value. Several limitations include: 1) coverage is limited to proximal coronary segments; 2) spatial resolution is low and often anisotropic; and 3) a separate magnetic resonance angiography acquisition is needed to localize lesions. Methods CATCH acquired dark-blood T1-weighted images and bright-blood anatomical reference images in an interleaved fashion. Retrospective motion correction with 100% respiratory gating efficiency was achieved. Reference control subjects (n = 13) completed both pre- and post-contrast scans. Stable angina patients (n = 30) completed pre-contrast scans, among whom 26 eligible patients also completed post-contrast scans. After cardiac magnetic resonance, eligible patients (n = 22) underwent invasive coronary angiography and OCT for the interrogation of coronary atherosclerosis. OCT images were assessed and scored for HRPF (lipid-richness, macrophages, cholesterol crystals, and microvessels) by 2 experienced analysts blinded to magnetic resonance results. Results Per-subject analysis showed none of the 13 reference control subjects had coronary hyperintensive plaques (CHIP) in either pre-contrast or post-contrast CATCH. Five patients had CHIP on pre-contrast CATCH and 5 patients had CHIP on post-contrast CATCH. Patients with CHIP had greater lipid abnormality than those without. Per-segment analysis showed elevated pre- and post-contrast plaque to myocardium signal ratio in the lesions with HRPF versus those without. Positive correlation was observed between plaque to myocardium signal ratio and OCT HRPF scoring. CHIP on pre-contrast CATCH were associated with significantly higher stenosis level than non-CHIP on invasive coronary angiography. Conclusions CATCH provided accelerated whole heart coronary plaque characterization with simultaneously acquired anatomical reference. CHIP detected by CATCH showed positive association with high-risk plaque features on invasive imaging studies.

BACKGROUND: To quantify the association between effects of interventions on carotid intima-media thickness (cIMT) progression and their effects on cardiovascular disease (CVD) risk. METHODS: We systematically collated data from randomized controlled trials. cIMT was assessed as the mean value at the common-carotid-artery; if unavailable, the maximum value at the common-carotid-artery or other cIMT measures were utilized. The primary outcome was a combined CVD endpoint defined as myocardial infarction, stroke, revascularization procedures, or fatal CVD. We estimated intervention effects on cIMT progression and incident CVD for each trial, before relating the two using a Bayesian meta-regression approach. RESULTS: We analyzed data of 119 randomized controlled trials involving 100,667 patients (mean age 62 years, 42% female). Over an average follow-up of 3.7 years, 12,038 patients developed the combined CVD endpoint. Across all interventions, each 10 μm/year reduction of cIMT progression resulted in a relative risk for CVD of 0.91 (95% credible interval 0.87-0.94), with an additional relative risk for CVD of 0.92 (0.87-0.97) being achieved independent of cIMT progression. Taken together, we estimated that interventions reducing cIMT progression by 10, 20, 30, or 40 μm/year would yield relative risks of 0.84 (0.75-0.93), 0.76 (0.67-0.85), 0.69 (0.59-0.79), or 0.63 (0.52-0.74). Results were similar when grouping trials by type of intervention, time of conduct, time to ultrasound follow-up, availability of individual-participant data, primary vs. secondary prevention trials, type of cIMT measurement, and proportion of female patients. CONCLUSIONS: The extent of intervention effects on cIMT progression predicted the degree of CVD risk reduction. This provides a missing link supporting the usefulness of cIMT progression as a surrogate marker for CVD risk in clinical trials.

Background Among patients with acute coronary syndrome (ACS) who do not have diabetes, incident diabetes is common and associated with an adverse prognosis. Some data suggest that high density lipoprotein (HDL) has favourable effects on beta cell function and that cholesteryl ester transfer protein (CETP) inhibitors reduce incident type 2 diabetes in conjunction with increased HDL cholesterol (HDL-C) concentration. Dalcetrapib is a CETP inhibitor under ongoing evaluation as a potential cardiovascular therapy. Purpose We compared the effect of treatment with dalcetrapib or placebo on incident diabetes in patients with recent acute coronary syndrome (ACS). Methods In the dal-OUTCOMES trial, 15,871 patients were randomly assigned to treatment with dalcetrapib 600 mg or placebo daily, beginning 4–12 weeks after ACS. Absence of diabetes at baseline was based upon medical history, no use of diabetes medication, haemoglobin A1c Results At baseline, 10621 patients (67% of the trial cohort) did not have diabetes and formed the analysis cohort. Over median follow-up of 31 months, incident diabetes was identified in 392 of 5314 patients (7.4%) assigned to dalcetrapib and 505 of 5307 (9.5%) assigned to placebo (odds ratio [OR] 0.76; 95% confidence interval [CI] 0.66–0.87; P Conclusions In patients with recent ACS who do not have diabetes at baseline, incident diabetes is common. Dalcetrapib treatment reduced the relative risk of incident diabetes by 24% and the absolute risk by 2.1% over a median of 31 months. The reduction in incident diabetes with dalcetrapib was associated with increased HDL-C on treatment. Acknowledgement/Funding The dal-OUTCOMES trial was funded by F. Hoffmann LaRoche

Atherosclerotic cardiovascular disease is a leading cause of death and morbidity globally. Over the past several years, arterial inflammation has been implicated in the pathophysiology of athero-thrombosis, substantially confirming what pathologist Rudolf Virchow had observed in the 19th century. Lipid lowering, lifestyle changes, and modification of other risk factors have reduced cardiovascular complications of athero-thrombosis, but a substantial residual risk remains. In view of the pathogenic role of inflammation in athero-thrombosis, directly targeting inflammation has emerged as an additional potential therapeutic option; and some early promising results have been suggested by the Canakinumab Anti-inflammatory Thrombosis Outcome Study (CANTOS), in which canakinumab, a fully human monoclonal antibody targeting the pro-inflammatory and pro-atherogenic cytokine interleukin 1 beta, was shown to reduce cardiovascular events.

Modulating inflammation by targeting IL-1β reduces recurrent athero-thrombotic cardiovascular events without lipid lowering. This presents an opportunity to explore other pathways associated with the IL-1β signaling cascade to modulate the inflammatory response post-myocardial infarction (MI). IL-7 is a mediator of the inflammatory pathway involved in monocyte trafficking into atherosclerotic plaques and levels of IL-7 have been shown to be elevated in patients with acute MI. Recurrent athero-thrombotic events are believed to be mediated in part by index MI-induced exacerbation of inflammation in atherosclerotic plaques. The objective of the study was to assess the feasibility of IL-7R blockade to modulate atherosclerotic plaque inflammation following acute MI in ApoE−/- mice. Mice were fed Western diet for 12 weeks and then subjected to coronary occlusion to induce an acute MI. IL-7 expression was determined using qRT-PCR and immuno-staining, and IL-7R was assessed using flow cytometry. Plaque inflammation was evaluated using immunohistochemistry. IL-7R blockade was accomplished with monoclonal antibody to IL-7R. IL-7 mRNA expression was significantly increased in the cardiac tissue of mice subjected to MI but not in controls. IL-7 staining was observed in the coronary artery. Plaque macrophage and lipid content were significantly increased after MI. IL-7R antibody treatment but not control IgG significantly reduced macrophage and lipid content in atherosclerotic plaques. The results show that IL-7R antibody treatment reduces monocyte/macrophage and lipid content in the atherosclerotic plaque following MI suggesting a potential new target to mitigate increased plaque inflammation post-MI., Highlights • Myocardial infarction increases inflammation in atherosclerotic plaques. • IL-7 is a mediator of inflammatory cell recruitment and is expressed in the ischemic myocardium. • Monoclonal antibody blockade of IL-7Rα reduced plaque lipid and macrophage content.

Atherosclerotic cardiovascular disease is a leading cause of death in much of the world. Adoption of a healthy lifestyle and cholesterol lowering are the key measures used to prevent major complications of atherosclerosis. Recent data have identified a critical role for inflammation mediated through activation of both innate and adaptive immune pathways in the pathophysiology of atherosclerosis opening up opportunities for development of anti-inflammatory interventions that could supplement risk factor modification and lipid lowering as an approach to further reducing the burden of atherosclerotic cardiovascular disease.

BackgroundBeta-blocker therapy after acute myocardial infarction (MI) improves survival. Beta-blocker doses used in clinical practice are often substantially lower than those used in the randomized trials establishing their efficacy.ObjectivesThis study evaluated the association of beta-blocker dose with survival after acute MI, hypothesizing that higher dose beta-blocker therapy will be associated with increased survival.MethodsA multicenter registry enrolled 7,057 consecutive patients with acute MI. Discharge beta-blocker dose was indexed to the target beta-blocker doses used in randomized clinical trials, grouped as >0% to 12.5%, >12.5% to 25%, >25% to 50%, and >50% of target dose. Follow-up vital status was assessed, with the primary endpoint of time-to-death right-censored at 2 years. Multivariable and propensity score analyses were used to account for group differences.ResultsOf 6,682 patients with follow-up (median 2.1 years), 91.5% were discharged on a beta-blocker (mean dose 38.1% of the target dose). Lower mortality was observed with all beta-blocker doses (p < 0.0002) versus no beta-blocker therapy. After multivariable adjustment, hazard ratios for 2-year mortality compared with the >50% dose were 0.862 (95% confidence interval [CI]: 0.677 to 1.098), 0.799 (95% CI: 0.635 to 1.005), and 0.963 (95% CI: 0.765 to 1.213) for the >0% to 12.5%, >12.5% to 25%, and >25% to 50% of target dose groups, respectively. Multivariable analysis with an extended set of covariates and propensity score analysis also demonstrated that higher doses were not associated with better outcome.ConclusionsThese data do not demonstrate increased survival in patients treated with beta-blocker doses approximating those used in previous randomized clinical trials compared with lower doses. These findings provide the rationale to re-engage in research to establish appropriate beta-blocker dosing after MI to derive optimal benefit from this therapy. (The PACE-MI Registry Study—Outcomes of Beta-blocker Therapy After Myocardial Infarction [OBTAIN]: NCT00430612)

ObjectiveLomitapide (a microsomal triglyceride transfer protein inhibitor) is an adjunctive treatment for homozygous familial hypercholesterolaemia (HoFH), a rare genetic condition characterised by elevated low-density lipoprotein-cholesterol (LDL-C), and premature, severe, accelerated atherosclerosis. Standard of care for HoFH includes lipid-lowering drugs and lipoprotein apheresis. We conducted a post-hoc analysis using data from a Phase 3 study to assess whether concomitant apheresis affected the lipid-lowering efficacy of lomitapide.MethodsExisting lipid-lowering therapy, including apheresis, was to remain stable from Week −6 to Week 26. Lomitapide dose was escalated on the basis of individual safety/tolerability from 5 mg to 60 mg a day (maximum). The primary endpoint was mean percent change in LDL-C from baseline to Week 26 (efficacy phase), after which patients remained on lomitapide through Week 78 for safety assessment and further evaluation of efficacy. During this latter period, apheresis could be adjusted. We analysed the impact of apheresis on LDL-C reductions in patients receiving lomitapide.ResultsOf the 29 patients that entered the efficacy phase, 18 (62%) were receiving apheresis at baseline. Twenty-three patients (13 receiving apheresis) completed the Week 26 evaluation. Of the six patients who discontinued in the first 26 weeks, five were receiving apheresis. There were no significant differences in percent change from baseline of LDL-C at Week 26 in patients treated (−48%) and not treated (−55%) with apheresis (p = 0.545). Changes in Lp(a) levels were modest and not different between groups (p = 0.436).ConclusionThe LDL-C lowering efficacy of lomitapide is unaffected by lipoprotein apheresis.

Epidemiological data associate higher concentrations of high-density lipoprotein cholesterol (HDL-C) with lower cardiovascular risk. HDL-C isolated from healthy subjects exhibits potentially protective properties, including anti-inflammatory effects [(1)][1]. However, some evidence suggests that