Functional Hypothalamic Amenorrhea and Preclinical Cardiovascular Disease

CONTEXT

Endothelial dysfunction is a preclinical cardiovascular disease (CVD) marker. Due to various neuroendocrine aberrations, functional hypothalamic amenorrhea (FHA) may be a sex-specific risk factor for CVD in young women.

OBJECTIVE

To investigate endothelial function in women with FHA, compared with eumenorrheic controls and recently menopausal women.

METHODS

We performed a cross-sectional analysis among women with FHA (n = 30), eumenorrheic controls (n = 29), and recently menopausal women (n = 30). FHA was defined as amenorrhea ≥3 consecutive months, estradiol <50 pg/mL, follicle-stimulating hormone (FSH) < 10 mIU/mL, and luteinizing hormone (LH) < 10 mIU/mL, excluding other etiologies. Participants were recruited through obstetrics and gynecology referrals, social media advertising, and review of electronic health records. Preclinical CVD was measured using EndoPAT 2000 to calculate reactive hyperemic index (RHI). RHI ≤1.67 indicates endothelial dysfunction.

RESULTS

Mean estradiol levels in women with FHA, as compared with eumenorrheic controls and recently menopausal women, were 29.0 ± 18.1, 46.4 ± 15.7, and 10.9 ± 14.4 pg/mL (P < .0001), respectively. Women with FHA had lower insulin (P = .0095) and higher cortisol (P = .0004) compared with controls. RHI was significantly lower in women with FHA compared with eumenorrheic controls and recently menopausal women (1.8 ± 0.5 vs 2.2 ± 0.5 vs 2.2 ± 0.6, respectively; P = .008), and 35% of women with FHA had RHI ≤1.67, consistent with endothelial dysfunction.

CONCLUSION

These results demonstrate endothelial dysfunction in 1 out of 3 young women with FHA. FHA may be a contributor to preclinical CVD, and it is not explained by hypoestrogenemia alone.

Differentiation between Descending Thoracic Aortic Diseases using Machine Learning and Plasma Proteomic Signatures

Background

Descending thoracic aortic aneurysms and dissections can go undetected until severe and catastrophic, and few clinical indices exist to screen for aneurysms or predict risk of dissection.

Methods

This study generated a plasma proteomic dataset from 75 patients with descending type B dissection (Type B) and 62 patients with descending thoracic aortic aneurysm (DTAA). Standard statistical approaches were compared to supervised machine learning (ML) algorithms to distinguish Type B from DTAA cases. Quantitatively similar proteins were clustered based on linkage distance from hierarchical clustering and ML models were trained with uncorrelated protein lists across various linkage distances with hyperparameter optimization using 5-fold cross validation. Permutation importance (PI) was used for ranking the most important predictor proteins of ML classification between disease states and the proteins among the top 10 PI protein groups were submitted for pathway analysis.

Results

Of the 1,549 peptides and 198 proteins used in this study, no peptides and only one protein, hemopexin (HPX), were significantly different at an adjusted p-value <0.01 between Type B and DTAA cases. The highest performing model on the training set (Support Vector Classifier) and its corresponding linkage distance (0.5) were used for evaluation of the test set, yielding a precision-recall area under the curve of 0.7 to classify between Type B from DTAA cases. The five proteins with the highest PI scores were immunoglobulin heavy variable 6-1 (IGHV6-1), lecithin-cholesterol acyltransferase (LCAT), coagulation factor 12 (F12), HPX, and immunoglobulin heavy variable 4-4 (IGHV4-4). All proteins from the top 10 most important correlated groups generated the following significantly enriched pathways in the plasma of Type B versus DTAA patients: complement activation, humoral immune response, and blood coagulation.

Conclusions

We conclude that ML may be useful in differentiating the plasma proteome of highly similar disease states that would otherwise not be distinguishable using statistics, and, in such cases, ML may enable prioritizing important proteins for model prediction.

Impaired tolerance to the autoantigen LL-37 in acute coronary syndrome

Background

LL-37 is the only member of the cathelicidin family of antimicrobial peptides in humans and is an autoantigen in several autoimmune diseases and in acute coronary syndrome (ACS). In this report, we profiled the specific T cell response to the autoimmune self-antigen LL-37 and investigated the factors modulating the response in peripheral blood mononuclear cells (PBMCs) of healthy subjects and ACS patients.

Methods and results

The activation induced marker (AIM) assay demonstrated differential T cell profiles characterized by the persistence of CD134 and CD137, markers that impair tolerance and promote immune effector and memory response, in ACS compared to Controls. Specifically, CD8+CD69+CD137+ T cells were significantly increased by LL-37 stimulation in ACS PBMCs. T effector cell response to LL-37 were either HLA dependent or independent as determined by blocking with monoclonal antibody to either Class-I HLA or Class-II HLA. Blocking of immune checkpoints PD-1 and CTLA-4 demonstrated the control of self-reactive T cell response to LL-37 was modulated predominantly by CTLA-4. Platelets from healthy controls down-modulated CD8+CD69+CD137+ T cell response to LL-37 in autologous PBMCs. CD8+CD69+CD137+ T cell AIM profile negatively correlated with platelet count in ACS patients.

Conclusions

Our report demonstrates that the immune response to the autoantigen LL-37 in ACS patients is characterized specifically by CD8+CD69+CD137+ T cell AIM profile with persistent T cell activation and the generation of immunologic memory. The results provide potentially novel insight into mechanistic pathways of antigen-specific immune signaling in ACS.

Electrocardiograms in Critical Care Cardiology

Patients with critical illness may present with electrocardiogram (ECG) findings with bizarre QRS morphology or abnormal amplitude. This article provides ECG examples from such clinical scenarios and discusses their clinical characteristics and significance. (Level of Difficulty: Beginner.).

Electrocardiograms in Critical Care Cardiology: Is it Acute Coronary Syndrome?

Patients with critical illness may present with electrocardiogram (ECG) findings difficult for physicians to distinguish them from acute coronary syndrome. This article provides three cases of such clinical scenarios. Examples of ECGs and their clinical characteristics and significance are discussed. (Level of Difficulty: Beginner.).

ECGs in Critical Care Cardiology: Do Not Miss That Myocardial Infarction

This paper provides clinical cases of acute myocardial infarction that do not show ST-segment elevation on 12-lead electrocardiogram, but should be clinically treated as ST-segment elevation myocardial infarction with early diagnostic coronary angiogram followed by appropriate strategy of revascularization. (Level of Difficulty: Beginner.).

Abstract P3132: High-salt Diet Increases Blood Cholesterol: Potential Role Of Hepatic Enzyme CYP51

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, p<0.0001; Tm7sf2 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.

Immunization using ApoB-100 peptide-linked nanoparticles reduces atherosclerosis

Active immunization with the apolipoprotein B-100 (ApoB-100) peptide P210 reduces experimental atherosclerosis. To advance this immunization strategy to future clinical testing, we explored the possibility of delivering P210 as an antigen using nanoparticles, given this approach has been used clinically. We first characterized the responses of T cells to P210 using PBMCs from patients with atherosclerotic cardiovascular disease (ASCVD). We then investigated the use of P210 in self-assembling peptide amphiphile micelles (P210-PAMs) as a vaccine formulation to reduce atherosclerosis in B6.129P2-Apoe^tm1Unc/J (ApoE^–/–) mice and P210’s potential mechanisms of action. We also generated and characterized a humanized mouse model with chimeric HLA-A*02:01/Kb in ApoE^–/– background to test the efficacy of P210-PAM immunization as a bridge to future clinical testing. P210 provoked T cell activation and memory response in PBMCs of patients with ASCVD. Dendritic cell uptake of P210-PAM and its costaining with MHC-I molecules supported its use as a vaccine formulation. In ApoE^–/– mice, immunization with P210-PAMs dampened P210-specific CD4⁺ T cell proliferative response and CD8⁺ T cell cytolytic response, modulated macrophage phenotype, and significantly reduced aortic atherosclerosis. Potential clinical relevance of P210-PAM immunization was demonstrated by reduced atherosclerosis in the humanized ApoE^–/– mouse model. Our data support experimental and translational use of P210-PAM as a potential vaccine candidate against human ASCVD.

Abstract 511: Intrinsic Self-reactive T Cells To ApoB-100 Peptide P210 In Acute Coronary Syndrome Patients Are Associated With T Effector/Memory Response

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<0.05; n=12) compared to controls (N=6). No other AIM+ cells were noted. P210 stimulation induced persistent CD8+ T Effector and T Effector Memory responses in ACS (N=13; P<0.05) compared to controls (N=14).

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.

Abstract 510: Immune-regulatory Mechanism Of P210-complexed Nanoparticle Immunization For Atherosclerosis

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<0.05). No effects were observed with non-specific PMA/ionomycin stimulation indicating antigen-specificity. Splenic mRNA expression of IL-1β was unchanged but there was significant reduction in IL-1R1, IL-6, and IL-17a in P210-PAM mice (N=12 each; P<0.05). Flow cytometric analysis indicated that the reduced IL-1R1 expression was specific to F4/80+ macrophages (N=10 each; P<0.05). Macrophages enriched from the peritoneal exudate showed significantly reduced iNOS, IL-6, IL-12 and IL-10 mRNA expression in P210-PAM mice compared to MSA-PAM (N=4 each; P<0.05).

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.

Intramyocardial Hemorrhage and the "Wave Front" of Reperfusion Injury Compromising Myocardial Salvage

BACKGROUND

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.

OBJECTIVES

Hemorrhage is known to occur in reperfused MIs, but whether hemorrhage plays a role in reperfusion-mediated MI expansion is not known.

METHODS

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.

RESULTS

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).

CONCLUSIONS

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.

A protocol for the Development of Core Outcome Sets for Endodontic Treatment modalities (COSET): an international consensus process

Background

The outcome of endodontic treatment is generally assessed using a range of patient and clinician-centred, non-standardised clinical and radiographic outcome measures. This makes it difficult to synthesise evidence for systematic analysis of the literature and the development of clinical guidelines. Core outcome sets (COS) represent a standardised list of outcomes that should be measured and reported in all clinical studies in a particular field. Recently, clinical researchers and guideline developers have focussed on the need for the integration of a patient-reported COS with clinician-centred measures. This study aims to develop a COS that includes both patient-reported outcomes and clinician-centred measures for various endodontic treatment modalities to be used in clinical research and practice.

Methods

To identify reported outcomes (including when and how they are measured), systematic reviews and their included clinical studies, which focus on the outcome of endodontic treatment and were published between 1990 and 2020 will be screened. The COSs will be defined by a consensus process involving key stakeholders using semi-structured interviews and an online Delphi methodology followed by an interactive virtual consensus meeting. A heterogeneous group of key ‘stakeholders’ including patients, general dental practitioners, endodontists, endodontic teachers, clinical researchers, students and policy-makers will be invited to participate. Patients will establish, via interactive interviews, which outcomes they value and feel should be included in a COS. In the Delphi process, other stakeholders will be asked to prioritise outcomes identified from the literature and patient interviews and will have the opportunity at the end of the first round to add outcomes that are not included, but which they consider relevant. Feedback will be provided in the second round, when participants will be asked to prioritise the list again. If consensus is reached, the remaining outcomes will be discussed at an online meeting and agreement established via defined consensus rules of outcome inclusion. If consensus is not reached after the second round, a third round will be conducted with feedback, followed by the online meeting. Following the identification of a COS, we will proceed to identify how and when these outcomes are measured.

Discussion

Using a rigorous methodology, the proposed consensus process aims to develop a COS for endodontic treatment that will be relevant to stakeholders. The results of the study will be shared with participants and COS users. To increase COS uptake, it will also be actively shared with clinical guideline developers, research funders and the editors of general dental and endodontology journals.

Trial registration

COMET 1879. 21 May 2021.

Association of Epicardial Fat Volume With the Extent of Coronary Atherosclerosis and Cardiovascular Adverse Events in Asymptomatic Patients With Diabetes

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.

Parallels between retinal and brain pathology and response to immunotherapy in old, late-stage Alzheimer's disease mouse models

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.

The Role of T Cells Reactive to the Cathelicidin Antimicrobial Peptide LL-37 in Acute Coronary Syndrome and Plaque Calcification

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.

Increased phagocytosis in the presence of enhanced M2-like macrophage responses correlates with increased primary and latent HSV-1 infection

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.

Targeting hypertriglyceridemia to mitigate cardiovascular risk: A review

A causal relationship between elevated triglycerides and cardiovascular disease is controversial, as trials of triglyceride-lowering treatments have not shown significant impact on cardiovascular outcomes. However, hypertriglyceridemia is associated with atherogenesis and risk for acute cardiovascular events that persist despite optimal statin treatment. Although most trials of triglyceride-lowering treatments have been negative, in trials of niacin and fibrates, subgroup analyses in patients with higher baseline triglycerides and lower HDL-C levels suggest reduced incidence of cardiovascular endpoints. The REDUCE-IT trial demonstrated that addition of purified prescription eicosapentaenoic acid (icosapent ethyl) 4 ​g/day in high-risk patients with triglyceride levels 135–499 ​mg/dL and optimized statin treatment significantly reduced cardiovascular events versus placebo (hazard ratio 0.75; 95% confidence interval 0.68–0.83; P ​< ​0.001). Benefit was seen regardless of baseline and on-treatment triglyceride levels, suggesting that other effects of eicosapentaenoic acid besides triglyceride reduction may have played a role.

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Hypertriglyceridemia is associated with atherogenesis & cardiovascular event risk.

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Most triglyceride treatment cardiovascular outcomes trials have been negative.

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However, icosapent ethyl significantly reduced cardiovascular events in REDUCE-IT.

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Effects of icosapent ethyl beyond triglyceride reduction may play a role.

PRICE 2020 guidelines for reporting case reports in Endodontics: explanation and elaboration

Case reports play a key role in showcasing new, unusual or rare disease(s), and the impact of newer therapeutic approaches or interventions. The Preferred Reporting Items for Case reports in Endodontics (PRICE) 2020 guidelines are being introduced exclusively for Endodontics by adapting and integrating the CAse REport (CARE) guidelines and Clinical and Laboratory Images in Publications principles. The PRICE 2020 guidelines have been developed to help authors improve the completeness, accuracy and transparency of case reports in Endodontics and thus enhance the standard of manuscripts submitted for publication. The aim of this document is to provide a comprehensive explanation for each item in the PRICE 2020 checklist along with examples from the literature that demonstrate compliance with these guidelines. This information will highlight the importance of each item and provide practical examples to help authors understand the necessity of providing comprehensive information when preparing case reports. A link to this PRICE 2020 explanation and elaboration document is available on the Preferred Reporting Items for study Designs in Endodontology website at http://www.pride-endodonticguidelines.org.

Dalcetrapib Reduces Risk of New-Onset Diabetes in Patients With Coronary Heart Disease

OBJECTIVE

Incident type 2 diabetes is common among patients with recent acute coronary syndrome and is associated with an adverse prognosis. Some data suggest that cholesteryl ester transfer protein (CETP) inhibitors reduce incident type 2 diabetes. We compared the effect of treatment with the CETP inhibitor dalcetrapib or placebo on incident diabetes in patients with recent acute coronary syndrome.

RESEARCH DESIGN AND METHODS

In the dal-OUTCOMES trial, 15,871 patients were randomly assigned to treatment with dalcetrapib 600 mg daily or placebo, beginning 4-12 weeks after an acute coronary syndrome. Absence of diabetes at baseline was based on medical history, no use of antihyperglycemic medication, and hemoglobin A_1c and serum glucose levels below diagnostic thresholds. Among these patients, incident diabetes after randomization was defined by any diabetes-related adverse event, new use of antihyperglycemic medication, hemoglobin A_1c ≥6.5%, or a combination of at least two measurements of serum glucose ≥7.0 mmol/L (fasting) or ≥11.1 mmol/L (random).

RESULTS

At baseline, 10,645 patients (67% of the trial cohort) did not have diabetes. During a median follow-up of 30 months, incident diabetes was identified in 403 of 5,326 patients (7.6%) assigned to dalcetrapib and in 516 of 5,319 (9.7%) assigned to placebo, corresponding to absolute risk reduction of 2.1%, hazard ratio of 0.77 (95% CI 0.68-0.88; P < 0.001), and a need to treat 40 patients for 3 years to prevent 1 incident case of diabetes. Considering only those with prediabetes at baseline, the number needed to treat for 3 years to prevent 1 incident case of diabetes was 25. Dalcetrapib also decreased the number of patients who progressed from normoglycemia to prediabetes and increased the number who regressed from diabetes to no diabetes.

CONCLUSIONS

In patients with a recent acute coronary syndrome, incident diabetes is common and is reduced substantially by treatment with dalcetrapib.

Sex as a Determinant of Responses to a Coronary Artery Disease Self-Antigen Identified by Immune-Peptidomics

A significant body of work implicates the adaptive immune response in atherosclerosis, the main underlying cause of coronary artery disease (CAD), yet specific antigens involved remain to be fully identified. The pathobiology of CAD is influenced by sex with many factors that may be involved in the underlying mechanisms. Given the reported sexual dimorphic nature of immune-inflammatory responses, we investigated the influence of sex on potential CAD self-antigens from acute coronary syndrome (ACS) patients using immune-precipitation of soluble HLA Class-I/peptide complexes and mass spectrometry. Relevance of identified self-antigens to atherosclerosis, the major underlying cause of CAD, was tested in the apoE–/– atherosclerotic mouse model. Soluble HLA Class-I complexes from ACS patients and self-reported controls were immune-precipitated and subjected to elution, denaturation and size-exclusion to obtain HLA-bound peptides. Peptides were then subjected to mass spectrometry and patient-unique self-peptides were grouped as common to both female and male, or unique to either sex. Three peptides common to both female and male patients (COL6A1, CDSN, and SAA2), and 2 peptides each unique to female (COL1A1 and COL5A2) or male (SAA1 and KRT 9) patients were selected and mouse homologs of the peptides were screened for self-reactive immune responses in apoE–/– mice. The screening step revealed potential sex-influenced immune responses which was associated with differential immune profiles. Based on the frequency in patient plasma, COL6A1, COL5A2, and KRT 9 peptides were then tested in immunization studies. Neither COL5A2 nor KRT 9 peptide immunization resulted in significant effects on atherosclerosis compared to controls. On the other hand, female mice immunized with COL6A1 peptide had significantly reduced atherosclerosis whereas male mice had significantly increased atherosclerosis, associated with differential immune profiles. Our study identified potential self-antigens involved in atherosclerosis using the immune peptidome of CAD patients. Altering self-reactive immune responses to COL6A1 in apoE–/– mice resulted in differential effects on atherosclerosis burden with sex as a determinant of outcome.

Association of high-density lipoprotein particle concentration with cardiovascular risk following acute coronary syndrome: A case-cohort analysis of the dal-Outcomes trial

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.

Intercepting the Lipid-Induced Integrated Stress Response Reduces Atherosclerosis

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.

P6193Dalcetrapib reduces incident diabetes in patients with recent acute coronary syndrome

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 <6.5%, and plasma glucose level <7 mmol/L (if measured under fasting conditions) or <11.1 mmol/L (if measured under non-fasting conditions). Among these patients, incident diabetes after randomization was defined by any diabetes-related adverse event, use of a diabetes medication, HbA1c ≥6.5%, or two measurements of plasma glucose ≥7 mmol/L (fasting) or ≥11.1 mmol/L (non-fasting). The association of incident diabetes with baseline and on-treatment HDL-C was determined.

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<0.001). This corresponds to an absolute reduction in incident diabetes of 2.1%, and a need to treat 47 patients (for 31 months) to prevent 1 case of diabetes. Kaplan-Meier estimates of the cumulative incidence of diabetes are shown in the Figure. Across both treatment groups, incident diabetes was inversely associated with baseline HDL-C (OR 0.98 for 1 mg/dL increase in baseline HDL-C; 95% CI 0.97–0.98, P<0.001). In the dalcetrapib group, there was a further inverse association of incident diabetes with the change in HDL-C on assigned treatment (OR 0.98 for 1 mg/dL increase in HDL-C from baseline; 95% CI 0.97–0.99, P=0.002). Dalcetrapib was safe and generally well-tolerated in the trial.

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

Deficiency of GATA3-Positive Macrophages Improves Cardiac Function Following Myocardial Infarction or Pressure Overload Hypertrophy

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 Ly6C^hi monocytes/macrophages and fewer reparative Ly6C^lo 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.

Association of Lipoprotein(a) With Risk of Recurrent Ischemic Events Following Acute Coronary Syndrome: Analysis of the dal-Outcomes Randomized Clinical Trial

Importance

It is uncertain whether lipoprotein(a) [Lp(a)], which is associated with incident cardiovascular disease, is an independent risk factor for recurrent cardiovascular events after acute coronary syndrome (ACS).

Objective

To determine the association of Lp(a) concentration measured after ACS with the subsequent risk of ischemic cardiovascular events.

Design, Setting, and Participants

This nested case-cohort analysis was performed as an ad hoc analysis of the dal-Outcomes randomized clinical trial. This trial compared dalcetrapib, the cholesteryl ester transfer protein inhibitor, with placebo in patients with recent ACS and was performed between April 2008 and September 2012 at 935 sites in 27 countries. There were 969 case patients who experienced a primary cardiovascular outcome, and there were 3170 control patients who were event free at the time of a case event and had the same type of index ACS (unstable angina or myocardial infarction) as that of the respective case patients. Concentration of Lp(a) was measured by immunoturbidimetric assay. Data analysis for this present study was conducted from June 8, 2016, to April 21, 2017.

Interventions

Patients were randomly assigned to receive treatment with dalcetrapib, 600 mg daily, or matching placebo, beginning 4 to 12 weeks after ACS.

Main Outcomes and Measures

Death due to coronary heart disease, a major nonfatal coronary event (myocardial infarction, hospitalization for unstable angina, or resuscitated cardiac arrest), or fatal or nonfatal ischemic stroke.

Results

The mean (SD) age was 63 (10) years for the 969 case patients and 60 (9) years for the 3170 control patients, and both cohorts were composed of predominantly male (770 case patients [79%] and 2558 control patients [81%]; P = .40) and white patients (858 case patients [89%] and 2825 control patients [89%]; P = .62). At baseline, the median (interquartile range) Lp(a) level was 12.3 (4.7-50.9) mg/dL. There was broad application of evidence-based secondary prevention strategies after ACS, including use of statins in 4030 patients (97%). The cumulative distribution of baseline Lp(a) levels did not differ between cases and controls at P = .16. Case-cohort regression analysis showed no association of baseline Lp(a) level with risk of cardiovascular events. For a doubling of Lp(a) concentration, the hazard ratio (case to control) was 1.01 (95% CI, 0.96-1.06; P = .66) after adjustment for 16 baseline variables, including assigned study treatment.

Conclusions and Relevance

For patients with recent ACS who are treated with statins, Lp(a) concentration was not associated with adverse cardiovascular outcomes. These findings call into question whether treatment specifically targeted to reduce Lp(a) levels would thereby lower the risk for ischemic cardiovascular events after ACS.

Trial Registration

clinicaltrials.gov Identifier: NCT00658515.

Inflammation in atherosclerotic cardiovascular disease

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.

Nanogel-Based Filler-Matrix Interphase for Polymerization Stress Reduction

A novel filler-resin matrix interphase structure was developed and evaluated for dental composite restoratives. Nanogel additives were chemically attached to the filler surface to use this created interphase as a potential source of compliance to minimize stress development during polymerization. In addition, we evaluated the effects of free nanogel dispersion into the resin matrix, combined or not with nanogel-modified fillers. Nanogels with varied characteristics were synthesized (i.e., size, 5 and 11 nm; glass transition temperature, 28 °C to 65 °C). Glass fillers were treated with trimethoxyvinylsilane and further reacted with thiol-functionalized nanogels via a free radical thiol-ene reaction. γ-Methacryloxypropyltrimethoxysilane-surface treated fillers were used as a control. Composites were formulated with BisGMA/TEGDMA resin blend with 60 wt% fillers with nanogel-modified fillers and/or free nanogel additives at 15 wt% in the resin phase. Polymerization kinetics, polymerization stress, volumetric shrinkage, and rheological and mechanical properties were evaluated to provide comprehensive characterization. Nanogel-modified fillers significantly reduced the polymerization stress from 2.2 MPa to 1.7 to 1.4 MPa, resulting in 20% stress reduction. A significantly greater nanogel content was required to generate the same magnitude stress reduction when the nanogels were dispersed only in the resin phase. When the nanogel-modified filler surface treatment and resin-dispersed nanogel strategies were combined, there was a stress reduction of 50% (values of 1.2 to 1.1 MPa). Polymerization rate and volumetric shrinkage were significantly reduced for systems with nanogel additives into the resin. Notably, the flexural modulus of the materials was not compromised, although a slight reduction in flexural strength associated with the nanogel-modified interphase was observed. Overall, modest amounts of free nanogel additives in the resin phase can be effectively combined with a limited nanogel content filler-resin interphase to lower volumetric shrinkage and dramatically reduce overall polymerization stress of composites.

Coronary artery calcium testing: A call for universal coverage

Heart attacks kill more Americans than all cancers combined. Fatal heart attack victims have no symptoms until minutes before they die, hence early detection of high-risk asymptomatic individuals is needed. Even though heart attacks kill and cost more than cancers, as a nation we spend over 20 times more on screening for asymptomatic cancer than for asymptomatic atherosclerotic cardiovascular disease (ASCVD), the underlying cause of heart attacks. Currently, payers only cover screening for risk factors of ASCVD such as blood pressure and blood cholesterol. This approach tends to miss high-risk and over-treat low-risk individuals. Although treadmill stress testing with ECG is not indicated for ASCVD detection in asymptomatic individuals, it is done often, and frequently leads to misleading conclusions or unnecessary downstream diagnostic procedures. For example, former President Clinton had passed his treadmill stress tests for several years during his presidential annual checkup but had a heart attack shortly after his presidency. This common practice is a waste of our limited resources. Instead, a more accurate risk assessment using coronary artery calcium (CAC) testing is available; and has just been adopted by ACC/AHA guidelines, however payers do not cover it. CAC is measured non-invasively with a 5-minute CT-scan of the heart, and costs less than $200, whereas cancer screening with colonoscopy and mammography costs over $3000. There is an opportunity to save lives and dollars if CAC testing is covered for appropriately selected individuals. Texas has already passed HB1290 to mandate CAC coverage. Other states must step up and take actions.

Keratin 8 is a potential self-antigen in the coronary artery disease immunopeptidome: A translational approach

Background

Inflammation is an important risk factor in atherosclerosis, the underlying cause of coronary artery disease (CAD). Unresolved inflammation may result in maladaptive immune responses and lead to immune reactivity to self-antigens. We hypothesized that inflammation in CAD patients would manifest in immune reactivity to self-antigens detectable in soluble HLA-I/peptide complexes in the plasma.

Methods

Soluble HLA-I/peptide complexes were immuno-precipitated from plasma of male acute coronary syndrome (ACS) patients or age-matched controls and eluted peptides were subjected to mass spectrometry to generate the immunopeptidome. Self-peptides were ranked according to frequency and signal intensity, then mouse homologs of selected peptides were used to test immunologic recall in spleens of male apoE-/- mice fed either normal chow or high fat diet. The peptide detected with highest frequency in patient plasma samples and provoked T cell responses in mouse studies was selected for use as a self-antigen to stimulate CAD patient peripheral blood mononuclear cells (PBMCs).

Results

The immunopeptidome profile identified self-peptides unique to the CAD patients. The mouse homologs tested showed immune responses in apoE-/- mice. Keratin 8 was selected for further study in patient PBMCs which elicited T Effector cell responses in CAD patients compared to controls, associated with reduced PD-1 mRNA expression.

Conclusion

An immunopeptidomic strategy to search for self-antigens potentially involved in CAD identified Keratin 8. Self-reactive immune response to Keratin 8 may be an important factor in the inflammatory response in CAD.

Inflammation, infection and atherosclerosis

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.

Efficacy and Safety of Alirocumab in High-Risk Patients With Clinical Atherosclerotic Cardiovascular Disease and/or Heterozygous Familial Hypercholesterolemia (from 5 Placebo-Controlled ODYSSEY Trials)

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.

The cathelicidin protein CRAMP is a potential atherosclerosis self-antigen in ApoE(-/-) mice

Auto-immunity is believed to contribute to inflammation in atherosclerosis. The antimicrobial peptide LL-37, a fragment of the cathelicidin protein precursor hCAP18, was previously identified as an autoantigen in psoriasis. Given the reported link between psoriasis and coronary artery disease, the biological relevance of the autoantigen to atherosclerosis was tested in vitro using a truncated (t) form of the mouse homolog of hCAP18, CRAMP, on splenocytes from athero-prone ApoE(-/-) mice. Stimulation with tCRAMP resulted in increased CD8+ T cells with Central Memory and Effector Memory phenotypes in ApoE(-/-) mice, differentially activated by feeding with normal chow or high fat diet. Immunization of ApoE(-/-) with different doses of the shortened peptide (Cramp) resulted in differential outcomes with a lower dose reducing atherosclerosis whereas a higher dose exacerbating the disease with increased neutrophil infiltration of the atherosclerotic plaques. Low dose Cramp immunization also resulted in increased splenic CD8+ T cell degranulation and reduced CD11b+CD11c+ conventional dendritic cells (cDCs), whereas high dose increased CD11b+CD11c+ cDCs. Our results identified CRAMP, the mouse homolog of hCAP-18, as a potential self-antigen involved in the immune response to atherosclerosis in the ApoE(-/-) mouse model.

Identification of apoB-100 Peptide-Specific CD8+ T Cells in Atherosclerosis

Background

T cells are found in atherosclerotic plaques, with evidence supporting a potential role for CD8+ T cells in atherogenesis. Prior studies provide evidence of low‐density lipoprotein and apoB‐100 reactive T cells, yet specific epitopes relevant to the disease remain to be defined. The current study was undertaken to identify and characterize endogenous, antigen‐specific CD8+ T cells in atherosclerosis.

Methods and Results

A peptide fragment of apoB‐100 that tested positive for binding to the mouse MHC‐I allele H2K^b was used to generate a fluorescent‐labeled H2K^b pentamer and tested in apoE^−/− mice. H2K^b pentamer(+)CD8+ T cells were higher in apoE^−/− mice fed an atherogenic diet compared with those fed a normal chow. H2K^b pentamer (+)CD8+ T cells in atherogenic diet–fed mice had significantly increased effector memory phenotype with a shift in Vβ profile. H2K^b pentamer blocked lytic activity of CD8+ T cells from atherogenic diet–fed mice. Immunization of age‐matched apoE^−/− mice with the apoB‐100 peptide altered the immune‐dominant epitope of CD8+ T cells and reduced atherosclerosis.

Conclusions

Our study provides evidence of a self‐reactive, antigen‐specific CD8+ T‐cell population in apoE^−/− mice. Immune modulation using the peptide antigen reduced atherosclerosis in apoE^−/− mice.

Oxidized LDL activated eosinophil polarize macrophage phenotype from M2 to M1 through activation of CD36 scavenger receptor

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.