Anti-dsDNA Antibodies Increase the Cardiovascular Risk in Systemic Lupus Erythematosus Promoting a Distinctive Immune and Vascular Activation

Systemic lupus erythematosus and atherosclerosis: immune pathways and the uncharted territory of gut microbiota and metabolism

Patients with Systemic Lupus Erythematosus (SLE) are significantly more susceptible to atherosclerosis, which may elevate their mortality risk. The review explores recent understandings of the origins and remedies for atherosclerosis associated with SLE. Our focus is particularly on the consequences of immune system disparities, interruptions in intestinal bacteria, and metabolic complications. The influence of SLE on atherosclerosis extends past usual risk elements, including processes specific to the disease. The list encompasses excessive immune cell activity, production of autoantibodies, inflammatory responses. A variety of therapies for atherosclerosis linked to SLE encompass cholesterol-lowering medications, anti-inflammatory drugs, immune suppressors, antimalarials, interferon treatments, NET inhibitors, and methods aimed at T and B-cells. However, existing research has its shortcomings, necessitating additional clinical trials to ascertain the efficacy and security of these therapies. The direct interactions among SLE, gut microbiota, metabolism, and atherosclerosis is underexplored, presenting innovation opportunities. Research into specific gut microbial strains and metabolites' effects on immune responses and atherosclerosis progression in SLE patients is needed. Such research could uncover novel therapeutic targets and biomarkers, advancing prevention and treatment strategies for SLE cardiovascular complications.

Double-stranded DNA enhances platelet activation, thrombosis, and myocardial injury via cyclic GMP-AMP synthase

AIMS

Elevated dsDNA levels in ST-elevated myocardial infarction (STEMI) patients are associated with increased infarct size and worse clinical outcomes. However, the direct effect of dsDNA on platelet activation remains unclear. This study aims to investigate the direct influence of dsDNA on platelet activation, thrombosis, and the underlying mechanisms.

METHODS AND RESULTS

Analysis of clinical samples revealed elevated plasma dsDNA levels in STEMI patients, which positively correlated with platelet aggregation and markers of neutrophil extracellular traps such as MPO-DNA and CitH3. Platelet assays demonstrated the activation of the cGAS-STING pathway in platelets from STEMI patients. DsDNA directly potentiated platelet activation and thrombus formation. Mechanistic studies using G150 (cGAS inhibitor), H151 (STING inhibitor), and MCC950 (NLRP3 inhibitor), as well as cGAS-/-, STING-/-, and NLRP3-/- mice, showed that dsDNA activated cGAS, a previously unreported DNA sensor in platelets, and induced activation of the STING/NLRP3/caspase-1/IL-1β axis. This cascade enhanced platelet activation and thrombus formation. Platelet cGAS depletion or Palbociclib, a cGAS-STING inhibitor, approved by the FDA for advanced breast cancer, ameliorated myocardial ischaemia-reperfusion injury in ApoE-/- mice fed with a high-fat diet for 12 weeks.

CONCLUSIONS

These results suggested that dsDNA is a novel driver of platelet activation and thrombus formation in STEMI patients.

T-bet-expressing B cells promote atherosclerosis in apolipoprotein E-deficient mice

The humoral immune system influences the development of atherosclerosis, but the contributions of specific memory B cell subsets and IgG isotypes are poorly understood. We assessed the relationship between atherosclerosis and age-associated B cells (ABCs), a T-bet-expressing memory B cell subset that is enriched for IgG2c production and implicated in humoral autoimmunity. We found increased numbers of splenic CD11c+ ABCs in 6-mo-old, chow-fed Apoe-/- mice versus C57BL/6 control mice, which were exacerbated by high-fat diet. Deletion of T-bet in the B lineage in high-fat diet-fed Apoe-/- mice reduced aortic lesion area, and this correlated with decreased splenic CD11c+ B cells and reduced serum oxidized low-density lipoprotein-specific IgG2c. Our findings suggest that T-bet-expressing B cells are atherogenic agents in the Apoe-/- model and indicate that interventions to inhibit a T-bet-driven humoral response may improve atherosclerotic disease.

Acute Coronary Syndrome and Rheumatic Disease

Patients with rheumatic disease and immune disorders have been noted to show an earlier development of atherosclerosis and to present with acute coronary syndrome. These diseases disproportionately affect women, and patients frequently have a higher number of comorbidities and other risk factors. Inflammation has long been known to play a role in the development of coronary artery disease. Early studies have shown some benefit in treatment targeting inflammation. While this has not been realized for all populations, there remains potential in treatment with targeted and individualized therapies. Especially since these diseases are associated with a worse prognosis, management benefits from the multidisciplinary expertise of cardiologists, rheumatologists, and other providers. However, the prevention and treatment of underlying rheumatic disease remains essential. This review will seek to highlight prior studies and future directions in the treatment of acute coronary syndrome in patients with rheumatologic disease.

Evaluation of ocular surface inflammation and systemic conditions in patients with systemic lupus erythematosus: a cross-sectional study

OBJECTIVE

The cross-sectional study was designed to evaluate the association of ocular surface inflammation with systemic conditions in patients with systemic lupus erythematosus (SLE).

METHODS

The study enrolled 30 SLE patients and 30 controls. Ocular symptoms were evaluated using the Ocular Surface Disease Index (OSDI) questionnaire. Tear samples from all participants were collected for tear multi-cytokine and chemokine concentration analysis. All participants were assessed for dry eye disease (DED), including Schirmer I test, tear break-up time (TBUT), corneal fluorescein staining (CFS), meibomian gland secretion (MGS), lid-parallel conjunctival folds (LIPCOF), corneal clarity, and symblepharon. Besides, all participants were also examined for conjunctival impression cytology to measure the density of conjunctival goblet cells (CGCs). The peripheral blood indicators from SLE patients were also collected to measure the SLE-associated autoantibody specificities and systemic inflammatory indicators. Pearson and Spearman's analysis were uesd to examine the correlation between tear cytokines, CGCs, DED-related indicators, and systemic conditions.

RESULTS

The two groups were matched for age and gender in this study. 36.67% of eyes (11 in 30) of SLE patients and 13.33% of eyes (4 in 30) of controls were diagnosed with DED. OSDI scores, abnormal TBUT percentages, CFS percentages, and DED grading were all higher in SLE patients than in control group, while density of CGCs was lower. There were no significant differences in Schirmer I test, MGS, LIPCOF, corneal clarity, and symblepharon between SLE patients and controls. The levels of tear chemokine (C-X-C motif) ligand 11 (CXCL11) and cytokine interleukin-7 (IL-7) in patients with SLE were significantly higher than those in control group. Moreover, among SLE patients, the severity of DED and the level of tear chemokine CXCL11 were significantly positively correlated with SLE-associated autoantibody specificities.

CONCLUSION

Dry eye and tear cytokines and chemokines-mediated ocular surface inflammation persist in SLE patients and are associated with systemic conditions. Therefore, it is necessary for patients with SLE to combine systemic and ocular assessments.

Cardiovascular disease risk in systemic lupus erythematous: Certainties and controversies

Patients with systemic lupus erythematosus (SLE) experience greater cardiovascular morbidity and mortality compared to the general population. It is known that endothelial dysfunction, an early indicator of atherosclerosis development, can arise even without the presence of conventional cardiovascular risk factors. In fact, the risk factors contributing to cardiovascular disease can be classified into traditional risk factors and those uniquely associated with SLE such as disease activity, autoantibodies, etc.Furthermore, the pathogenesis of cardiovascular disease in SLE is linked to the activation of both the innate and adaptive immune systems. Given these findings, it is essential for clinicians to acknowledge the heightened CVD risk in SLE patients, perform comprehensive screenings for cardiovascular risk factors, and implement aggressive treatment strategies for those who exhibit signs of clinical CVD. The aim of this review is to summarize the findings on cardiovascular disease in SLE and to examine potential screening and therapeutic strategies for clinical practice.

Pathological mechanisms and crosstalk among various cell death pathways in cardiac involvement of systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a prevalent autoimmune disease primarily characterized by the involvement of multiple systems and organs. Cardiovascular disease is the primary cause of mortality in patients with SLE, though the mechanisms underlying the increased cardiovascular risk in SLE patients remain unclear. Recent studies indicate that abnormal activation of programmed cell death (PCD) signaling and the crosstalk among various forms of cell death are critical in the immunopathogenesis of SLE. Furthermore, apoptosis, necroptosis, pyroptosis, NETosis, and ferroptosis are recognized as key cellular processes in the pathogenesis of SLE and are closely linked to cardiac involvement. This review uniquely explores the intricate crosstalk between apoptosis, necroptosis, and other cell death pathways, discussing their roles and interactions in the pathogenesis of cardiac involvement in SLE. Investigating the interplay between PCD signaling and cardiac involvement in SLE in understanding the disease's underlying mechanisms and offers opportunities for new therapeutic interventions. The integration of precision medicine and innovative strategies targeting these complex pathways holds promise for enhancing the treatment prospects of SLE with cardiac involvement.

Beneficial effects of rapamycin on endothelial function in systemic lupus erythematosus

Introduction

Endothelial function is significantly impaired in patients with SLE compared to healthy controls. Elevated activation of the mammalian target of rapamycin complex 1 (mTORC1) is reported in humans and mice with SLE. However, it is unclear if elevated mTORC1 in SLE contributes to impaired mitophagy and endothelial dysfunction. Therefore, we tested the hypothesis that inhibiting mTORC1 with rapamycin would increase mitophagy and attenuate endothelial dysfunction and inflammatory responses in SLE.

Methods

Nine-week-old female lupus-prone (MRL/lpr) and healthy control (MRL/MpJ) mice were randomly assigned into rapamycin treatment (lpr_Rapamycin and MpJ_Rapamycin) or control (lpr_Control and MpJ_Control) groups. Rapamycin was injected i.p. 3 days per week for 8 weeks. After 8 weeks, endothelium-dependent vasorelaxation to acetylcholine (ACh) and endothelium-independent vasorelaxation to sodium nitroprusside (SNP) were measured in thoracic aortas using a wire myograph.

Results

MTORC1 activity was increased in aorta from lpr mice as demonstrated by increased phosphorylation of s6rp and p70s6k and significantly inhibited by rapamycin (s6rp, p < 0.0001, p70s6k, p = 0.04, respectively). Maximal responses to Ach were significantly impaired in lpr_Control (51.7% ± 6.6%) compared to MpJ_Control (86.7% ± 3.6%) (p < 0.0001). Rapamycin prevented endothelial dysfunction in the thoracic aorta from lupus mice (lpr_Rapamycin) (79.6% ± 4.2%) compared to lpr_Control (p = 0.002). Maximal responses to SNP were not different across groups. Phosphorylation of endothelial nitric oxide synthase also was 42% lower in lpr_Control than MpJ_Control and 46% higher in lpr_Rapamycin than lpr_Control. The inflammatory marker, vascular cell adhesion protein 1 (Vcam 1), was elevated in aorta from lupus mice compared with healthy mice (p = 0.001), and significantly reduced with Rapamycin treatment (p = 0.0021). Mitophagy markers were higher in lupus mice and reduced by rapamycin treatment, suggesting altered mitophagy in lpr mice.

Conclusion

Collectively, these results demonstrate the beneficial effects of inhibiting mTORC1 on endothelial function in SLE mice and suggest inflammation and altered mitophagy contribute to endothelial dysfunction in SLE.

Proposal of a novel cardiovascular risk prediction score in lupus nephritis

Introduction

Patients with systemic lupus erythematosus are prone to develop cardiovascular disease (CVD), and have increased morbidity and mortality.

Methods

We conducted a retrospective analysis on lupus nephritis patients to assess the occurrence and predictors of major adverse cardiovascular events (MACE). Data were collected from patients who underwent kidney biopsy between 2005 and 2020. Statistical analysis was performed to unveil correlations.

Results

91 patients were analyzed in this period, with a mean age of 37.3 ± 12.3 years and 86% being female. The mean follow-up time was 62 ± 48 months. 15.38% of the patients underwent at least one MACE. Two patients deceased of CVD. Increased age (35.81 ± 11.14 vs 45.5 ± 15.11 years, p=0.012) entailed a higher occurrence of MACEs. Neutrophil count (5.15 ± 2.83 vs 7.3 ± 2.99 Giga/L, p=0.001) was higher, whereas diastolic blood pressure (DBP) was lower (89.51 ± 10.96 vs 78.43 ± 6.9 mmHg, p<0.001) at the time of the biopsy in patients with MACE. Age, neutrophil count, and DBP proved to be independent predictors of MACEs. We propose a new model (CANDE - Cardiovascular risk based on Age, Neutrophil count, and Diastolic blood pressure Estimation score) calculated from these variables, which predicts the probability of MACE occurrence.

Conclusion

This study underscores the importance of actively screening for cardiovascular risks in this vulnerable patient population. Age, neutrophil count, and diastolic blood pressure have been established as independent risk factors for MACE in lupus nephritis. The CANDE score derived from these parameters may serve as a prompt, cost-effective, and easily accessible estimation tool for assessing the likelihood of major adverse cardiovascular risk. These findings emphasize the necessity for comprehensive management strategies addressing both immune dysregulation and cardiovascular risk factors in systemic lupus erythematosus to mitigate adverse outcomes.

Crosstalk between Inflammation and Atherosclerosis in Rheumatoid Arthritis and Systemic Lupus Erythematosus: Is There a Common Basis?

Cardiovascular disease is the leading cause of morbidity and mortality in patients with rheumatoid arthritis and systemic lupus erythematosus. Traditional cardiovascular risk factors, although present in lupus and rheumatoid arthritis, do not explain such a high burden of early cardiovascular disease in the context of these systemic connective tissue diseases. Over the past few years, our understanding of the pathophysiology of atherosclerosis has changed from it being a lipid-centric to an inflammation-centric process. In this review, we examine the pathogenesis of atherosclerosis in systemic lupus erythematosus and rheumatoid arthritis, the two most common systemic connective tissue diseases, and consider them as emblematic models of the effect of chronic inflammation on the human body. We explore the roles of the inflammasome, cells of the innate and acquired immune system, neutrophils, macrophages, lymphocytes, chemokines and soluble pro-inflammatory cytokines in rheumatoid arthritis and systemic lupus erythematosus, and the roles of certain autoantigens and autoantibodies, such as oxidized low-density lipoprotein and beta2-glycoprotein, which may play a pathogenetic role in atherosclerosis progression.

Novel Imaging Approaches to Cardiac Manifestations of Systemic Inflammatory Diseases: JACC Scientific Statement

Derangements in the innate and adaptive immune responses observed in systemic inflammatory syndromes contributes to unique elevated atherosclerotic risk and incident cardiovascular disease. Novel multimodality imaging techniques may improve diagnostic precision for the screening and monitoring of disease activity. The integrated application of these technologies lead to earlier diagnosis and noninvasive monitoring of cardiac involvement in systemic inflammatory diseases that will aid in preclinical studies, enhance patient selection, and provide surrogate endpoints in clinical trials, thereby improving clinical outcomes. We review the common cardiovascular manifestations of immune-mediated systemic inflammatory diseases and address the clinical and investigational role of advanced multimodality cardiac imaging.

An Emerging Role for Anti-DNA Antibodies in Systemic Lupus Erythematosus

Anti-DNA antibodies are hallmark autoantibodies produced in systemic lupus erythematosus (SLE), but their pathogenetic role is not fully understood. Accumulating evidence suggests that some anti-DNA antibodies enter different types of live cells and affect the pathophysiology of SLE by stimulating or impairing these cells. Circulating neutrophils in SLE are activated by a type I interferon or other stimuli and are primed to release neutrophil extracellular traps (NETs) on additional stimulation. Anti-DNA antibodies are also involved in this process and may induce NET release. Thereafter, they bind and protect extracellular DNA in the NETs from digestion by nucleases, resulting in increased NET immunogenicity. This review discusses the pathogenetic role of anti-DNA antibodies in SLE, mainly focusing on recent progress in the two research fields concerning antibody penetration into live cells and NETosis.

Update of Potential Biomarkers in Risk Prediction and Monitoring of Atherosclerosis in Systemic Lupus Erythematosus to Prevent Cardiovascular Disease

Systemic lupus erythematosus is a chronic connective tissue disease associated with an increased risk of premature atherosclerosis. It is estimated that approximately 10% of SLE patients develop significant atherosclerosis each year, which is responsible for premature cardiovascular disease that is largely asymptomatic. This review summarizes the most recent reports from the past few years on biomarkers of atherosclerosis in SLE, mainly focusing on immune markers. Persistent chronic inflammation of the vascular wall is an important cause of cardiovascular disease (CVD) events related to endothelial dysfunction, cell proliferation, impaired production and function of nitric oxide and microangiopathic changes. Studies on pathogenic immune mediators involved in atherosclerosis will be crucial research avenues for preventing CVD.

Immune Thrombosis: Exploring the Significance of Immune Complexes and NETosis

Neutrophil extracellular traps (NETs) are major contributors to inflammation and autoimmunity, playing a key role in the development of thrombotic disorders. NETs, composed of DNA, histones, and numerous other proteins serve as scaffolds for thrombus formation and promote platelet activation, coagulation, and endothelial dysfunction. Accumulating evidence indicates that NETs mediate thrombosis in autoimmune diseases, viral and bacterial infections, cancer, and cardiovascular disease. This article reviews the role and mechanisms of immune complexes in NETs formation and their contribution to the generation of a prothrombotic state. Immune complexes are formed by interactions between antigens and antibodies and can induce NETosis by the direct activation of neutrophils via Fc receptors, via platelet activation, and through endothelial inflammation. We discuss the mechanisms by which NETs induced by immune complexes contribute to immune thrombotic processes and consider the potential development of therapeutic strategies. Targeting immune complexes and NETosis hold promise for mitigating thrombotic events and reducing the burden of immune thrombosis.

Neutrophil extracellular traps contributing to atherosclerosis: From pathophysiology to clinical implications

Neutrophil extracellular traps (NETs) are network-like structures of chromatin filaments decorated by histones, granules, and cytoplasmic-derived proteins expelled by activated neutrophils under multiple pathogenic conditions. NETs not only capture pathogens in innate immunity but also respond to sterile inflammatory stimuli in atherosclerosis, such as lipoproteins and inflammatory cytokines. Atherosclerosis is a lipid-driven chronic inflammatory disease characterized by the accumulation and transformation of inflammatory cells, and smooth muscle cells in the intimal space. NETs-derived extracellular components possess toxic and proinflammatory properties leading to cellular dysfunction and tissue damage, which may establish a link among lipid metabolism, inflammatory immunity, and atherosclerosis. In this review, we discuss recent advances regarding the role of NETs engaged in the pathogenesis of atherosclerosis, particularly focusing on the interaction with lipids and inflammasomes, crosstalk with smooth muscle cells and inflammatory cells, and the association with aging. We also evaluate the current knowledge on the potential of NETs as biomarkers and therapeutic targets for atherosclerosis and its related diseases in clinical practice.

Neutrophil extracellular traps (NET): not only antimicrobial but also modulators of innate and adaptive immunities in inflammatory autoimmune diseases

Polymorphonuclear neutrophils (PMN) represent one of the first lines of defence against invading pathogens and are the most abundant leucocytes in the circulation. Generally described as pro-inflammatory cells, recent data suggest that PMN also have immunomodulatory capacities. In response to certain stimuli, activated PMN expel neutrophil extracellular traps (NET), structures made of DNA and associated proteins. Although originally described as an innate immune mechanism fighting bacterial infection, NET formation (or probably rather an excess of NET together with impaired clearance of NET) may be deleterious. Indeed, NET have been implicated in the development of several inflammatory and autoimmune diseases as rheumatoid arthritis or systemic lupus erythematosus, as well as fibrosis or cancer. They have been suggested as a source of (neo)autoantigens or regulatory proteins like proteases or to act as a physical barrier. Different mechanisms of NET formation have been described, leading to PMN death or not, depending on the stimulus. Interestingly, NET may be both pro-inflammatory and anti-inflammatory and this probably partly depends on the mechanism, and thus the stimuli, triggering NET formation. Within this review, we will describe the pro-inflammatory and anti-inflammatory activities of NET and especially how NET may modulate immune responses.

Acute Myocardial Infarction as the First Presentation of Systemic Lupus Erythematosus in a 23-Year-Old Patient

ST-segment elevation myocardial infarction (STEMI) in young adults is a rare occurrence that requires a thorough investigation to determine the underlying cause. Herein, a young female patient presented with dull retrosternal chest pain associated with nausea and left arm numbness. Cardiac-specific troponin was elevated and the electrocardiogram revealed ST-segment elevation in the inferior wall leads indicative of myocardial infarction. The patient was started on dual antiplatelet therapy (DAPT) and emergency coronary angiography was performed, revealing a 20% stenosis in the left circumflex artery and evidence of a thrombotic lesion in the posterolateral branch (PLB), which was deemed unsuitable for intervention. During the diagnostic workup, the patient tested positive for antinuclear antibodies and was ultimately diagnosed with systemic lupus erythematosus (SLE) and antiphospholipid syndrome. This case highlights the rarity of STEMI as an initial presentation of SLE. It emphasizes the importance of considering autoimmune disorders in young patients with acute myocardial infarction and the need for a comprehensive evaluation and appropriate management in such cases.

Anti-double stranded DNA antibodies: Electrochemical isotyping in autoimmune and neurological diseases

This work reports the first amperometric biosensor for the simultaneous determination of the single or total content of the most relevant human immunoglobulin isotypes (hIgs) of anti-dsDNA antibodies, dsDNA-hIgG, dsDNA-hIgM, dsDNA-hIgA and dsDNA-three hIgs, which are considered relevant biomarkers in prevalent autoimmune diseases such as systemic lupus erythematosus (SLE) as well as of interest in neurodegenerative diseases such as Alzheimer's disease (AD). The bioplatform involves the use of neutravidin-functionalized magnetic microparticles (NA-MBs) modified with a laboratory-prepared biotinylated human double-stranded DNA (b-dsDNA) for the efficient capture of specific autoantibodies that are enzymatically labeled with horseradish peroxidase (HRP) enzyme using specific secondary antibodies for each isotype or a mixture of secondary antibodies for the total content of the three isotypes. Transduction was performed by amperometry (-0.20 V vs. the Ag pseudo-reference electrode) using the H₂O₂/hydroquinone (HQ) system after trapping the resulting magnetic bioconjugates on each of the four working electrodes of a disposable quadruple transduction platform (SP₄CEs). The bioplatform demonstrated attractive operational characteristics for clinical application and was employed to determine the individual or total hIgs classes in serum from healthy individuals and from patients diagnosed with SLE and AD. The target concentrations in AD patients are provided for the first time in this work. In addition, the results for SLE patients and control individuals agree with those obtained by applying ELISA tests as well as with the clinical ranges reported by other authors, using individual detection methodologies restricted to centralized settings or clinical laboratories.

Markers of NETosis in Patients with Systemic Lupus Erythematosus and Antiphospholipid Syndrome

Neutrophil Extracellular Traps (NETs) have been implicated in systemic lupus erythematosus (SLE) and antiphospholipid syndrome (APS) pathogenesis. The myeloperoxidase-deoxyribonucleic acid (MPO-DNA) complex and nucleosomes are serum markers of NETosis. The aim of this study was to assess these NETosis parameters as markers for SLE and APS diagnosis and their association with clinical features and disease activity. A total of 138 people were included in the cross-sectional study: 30 with SLE without APS, 47 with SLE and APS, 41 patients with primary antiphospholipid syndrome (PAPS), and 20 seemingly healthy individuals. Serum MPO-DNA complex and nucleosome levels were determined via an enzyme-linked immunosorbent assay (ELISA). Informed consent was obtained from all subjects involved in the study. The Ethics Committee of the V.A. Nasonova Research Institute of Rheumatology (Protocol No. 25 dated 23 December 2021) approved the study. In patients with SLE without APS, the levels of the MPO-DNA complex were significantly higher compared to patients with SLE with APS, with PAPS, and healthy controls (p < 0.0001). Among patients with a reliable diagnosis of SLE, 30 had positive values of the MPO-DNA complex, of whom 18 had SLE without APS, and 12 had SLE with APS. Patients with SLE and positive MPO-DNA complex levels were significantly more likely to have high SLE activity (χ² = 5.25, p = 0.037), lupus glomerulonephritis (χ² = 6.82, p = 0.009), positive antibodies to dsDNA (χ² = 4.82, p = 0.036), and hypocomplementemia (χ² = 6.72, p = 0.01). Elevated MPO-DNA levels were observed in 22 patients with APS: 12 with SLE with APS and 10 with PAPS. There were no significant associations between positive levels of the MPO-DNA complex and clinical and laboratory manifestations of APS. The concentration of nucleosomes was significantly lower in the group of SLE patients (±APS) compared to controls and PAPS (p < 0.0001). In SLE patients, the frequency of low nucleosome levels was associated with high SLE activity (χ² = 13.4, p < 0.0001), lupus nephritis (χ² = 4.1, p = 0.043), and arthritis (χ² = 3.89, p = 0.048). An increase in the specific marker of NETosis, the MPO-DNA complex, was found in the blood serum of SLE patients without APS. Elevated levels of the MPO-DNA complex can be regarded as a promising biomarker of lupus nephritis, disease activity, and immunological disorders in SLE patients. Lower levels of nucleosomes were significantly associated with SLE (±APS). Low nucleosome levels were more common in patients with high SLE activity, lupus nephritis, and arthritis.

Amelioration of nephritis in receptor for advanced glycation end-products (RAGE)-deficient lupus-prone mice through neutrophil extracellular traps

The receptor for advanced glycation end-products (RAGE) is a pattern recognition receptor that regulates inflammation, cell migration, and cell fate. Systemic lupus erythematosus (SLE) is a chronic multiorgan autoimmune disease. To understand the function of RAGE in SLE, we generated RAGE-deficient (Ager-/-) lupus-prone mice by backcrossing MRL/MpJ-Faslpr/J (MRL-lpr) mice with Ager-/- C57BL/6 mice. In 18-week-old Ager-/- MRL-lpr, the weights of the spleen and lymph nodes, as well as the frequency of CD3+CD4-CD8- cells, were significantly decreased. Ager-/- MRL-lpr mice had significantly reduced urine albumin/creatinine ratios and markedly improved renal pathological scores. Moreover, neutrophil infiltration and neutrophil extracellular trap formation in the glomerulus were significantly reduced in Ager-/- MRL-lpr. Our study is the first to reveal that RAGE can have a pathologic role in immune cells, particularly neutrophils and T cells, in inflammatory tissues and suggests that the inhibition of RAGE may be a potential therapeutic strategy for SLE.

Splicing machinery is profoundly altered in systemic lupus erythematosus and antiphospholipid syndrome and directly linked to key clinical features

OBJECTIVES

To characterize the splicing machinery (SM) of leukocytes from primary antiphospholipid syndrome (APS), systemic lupus erythematosus (SLE) and antiphospholipid syndrome with lupus (APS + SLE) patients, and to assess its clinical involvement.

METHODS

Monocytes, lymphocytes and neutrophils from 80 patients (22 APS, 35 SLE and 23 APS + SLE) and 50 HD were purified, and 45 selected SM components were evaluated by qPCR-microfluidic array. Relationship with clinical features and underlying regulatory mechanisms were assessed.

RESULTS

APS, SLE and APS + SLE leukocytes displayed significant and specific alterations in SM-components (SMC), associated with clinical features [autoimmune profiles, disease activity, lupus nephritis (LN), and CV-risk markers]. A remarkable relationship among dysregulated SMC in monocytes and the presence of LN in SLE was highlighted, revealing a novel pathological mechanism, which was further explored. Immunohistology analysis of renal biopsies highlighted the pathological role of the myeloid compartment in LN. Transcriptomic analysis of monocytes from SLE-LN(+) vs SLE-LN(-) identified 271 genes differentially expressed, mainly involved in inflammation and IFN-signaling. Levels of IFN-related genes correlated with those of SMC in SLE-LN(+). These results were validated in two external SLE-LN(+) datasets of whole-blood and kidney biopsies. In vitro, SLE-LN(+)-serum promoted a concomitant dysregulation of both, the IFN signature and several SMC, further reversed by JAKinibs treatment. Interestingly, IFNs, key inflammatory cytokines in SLE pathology, also altered SMC. Lastly, the over/down-expression of selected SMC in SLE-monocytes reduced the release of inflammatory cytokines and their adhesion capacity.

CONCLUSION

Overall, we have identified, for the first time, a specific alteration of SMC in leukocytes from APS, SLE and APS + SLE patients that would be responsible for the development of distinctive clinical profiles.

Soluble LILRA3 is aberrantly expressed in antiphospholipid syndrome (APS) and is a potential marker of thrombotic APS

OBJECTIVE

Leucocyte immunoglobulin-like receptor A3 (LILRA3) belongs to a family of leucocyte receptors. Our previous study reported LILRA3 transcripts were markedly upregulated in neutrophils from patients with APS. We undertook this study to investigate clinical implications of LILRA3 in APS and its potential role in APS-associated thrombosis.

METHODS

Two independent cohorts were studied. The first consisted of 294 APS patients, 48 asymptomatic aPL carriers and 150 healthy controls (HCs) from Peking University People's Hospital. The second included 99 APS patients, 25 aPL carriers and 40 HCs from United States APS centres. Serum or plasma concentrations of LILRA3 and MPO-DNA complexes were measured. Additionally, 35 patients with thrombotic APS (tAPS) were evaluated to determine potential effects of immunosuppressive therapy on serum concentrations of LILRA3 and MPO-DNA complexes.

RESULTS

Both positivity and serum concentration of LILRA3 were significantly increased in APS patients, especially in those with tAPS. LILRA3-positive tAPS patients displayed more severe thrombotic manifestations. Serum LILRA3 was positively correlated with MPO-DNA complexes in LILRA3-positive tAPS. After immunosuppressive treatment, LILRA3 and MPO-DNA complexes were consistently decreased in tAPS patients. Key findings from the Peking cohort were confirmed in the United States cohort.

CONCLUSION

Our study provides first evidence that LILRA3 is aberrantly expressed in APS, especially in patients with tAPS. Serum LILRA3 correlated with MPO-DNA complexes, and the two indices were consistently decreased in tAPS patients after treatment. LILRA3 may play a role in thrombosis of APS and may serve as a biomarker and/or therapeutic target in tAPS.

Obesity, Diabetes, and Cardiovascular Risk Burden in Systemic Lupus Erythematosus: Current Approaches and Knowledge Gaps-A Rapid Scoping Review

Obesity, diabetes mellitus, and cardiovascular risk are real challenges in systemic lupus erythematosus (SLE) clinical practice and research. The evidence of the burden of these health problems in SLE patients is determined by the methods used to assess them. Therefore, the aim of this scoping review is to map current approaches in assessing obesity, diabetes mellitus, and cardiovascular risk burden in SLE patients and to identify existing knowledge gaps in this field. This rapid scoping review was conducted according to the Joanna Briggs Institute methodology and identified 274 articles, of which 73 were included. Most studies were conducted at European institutions and patients were recruited from specialist hospital clinics, the majority of whom were women. The burden of obesity and diabetes mellitus for SLE patients was assessed mainly in terms of prevalence, impact on disease activity, and cardiometabolic risk. The burden of cardiovascular risk was assessed using multiple approaches, mainly imaging and laboratory methods, and risk factor-based scores, although there is great heterogeneity and uncertainty between the methods used. This review highlights the importance of improving and standardizing the approach to obesity, diabetes, and cardiovascular risk in SLE patients through a holistic assessment that includes lifestyle, clinical, biological, and social aspects.

Severe Neuro-COVID is associated with peripheral immune signatures, autoimmunity and neurodegeneration: a prospective cross-sectional study

Growing evidence links COVID-19 with acute and long-term neurological dysfunction. However, the pathophysiological mechanisms resulting in central nervous system involvement remain unclear, posing both diagnostic and therapeutic challenges. Here we show outcomes of a cross-sectional clinical study (NCT04472013) including clinical and imaging data and corresponding multidimensional characterization of immune mediators in the cerebrospinal fluid (CSF) and plasma of patients belonging to different Neuro-COVID severity classes. The most prominent signs of severe Neuro-COVID are blood-brain barrier (BBB) impairment, elevated microglia activation markers and a polyclonal B cell response targeting self-antigens and non-self-antigens. COVID-19 patients show decreased regional brain volumes associating with specific CSF parameters, however, COVID-19 patients characterized by plasma cytokine storm are presenting with a non-inflammatory CSF profile. Post-acute COVID-19 syndrome strongly associates with a distinctive set of CSF and plasma mediators. Collectively, we identify several potentially actionable targets to prevent or intervene with the neurological consequences of SARS-CoV-2 infection.

Immune mechanisms associated with cardiovascular disease in systemic lupus erythematosus: A path to potential biomarkers

Systemic lupus erythematosus (SLE) patients display an increased risk of cardiovascular disease (CVD). With the improved clinical management of other classical severe manifestation of the disease, CVD is becoming one of the most relevant complications of SLE, and it is an important factor causing morbidity and mortality. Several immune constituents have been shown to be involved in the pathogenesis of atherosclerosis and endothelial damage in SLE patients, including specific circulating cell populations, autoantibodies, and inflammatory mediators. In this review, we summarize the presentation of CVD in SLE and the role of the autoimmune responses present in SLE patients in the induction of atherogenesis, endothelial impairment and cardiac disease. Additionally, we discuss the utility of these immune mediators as early CVD biomarkers and targets for clinical intervention in SLE patients.

Spontaneous coronary artery dissection and atherosclerosis in a young man with systemic lupus erythematosus: A case report and literature review

Background

Spontaneous coronary artery dissection (SCAD) is a rare coronary artery disease that frequently occurs in young, female patients without risk factors, and conservative treatment is often recommended for its management. The patient reported here is a male patient with systemic lupus erythematosus (SLE).

Case summary

We described a 28-year-old man with SLE who presented with acute ST-segment elevation myocardial infarction (STEMI), and was diagnosed with SCAD through a long dissection of the left anterior descending branch (LAD) by coronary angiography. The patient was treated with percutaneous coronary intervention (PCI) with stent implantation. Ten years later, he developed in-stent stenosis and other coronary atherosclerosis and was retreated with PCIs. Based on this case and according to the literature review, the existing treatment and prognosis of SLE with spontaneous coronary artery dissection and atherosclerosis are discussed.

Conclusion

Cardiovascular complications should be considered in patients with systemic lupus erythematosus, although they may not initially be atherosclerotic diseases. Attention should be paid to distinguish spontaneous coronary dissection in order to minimize missed or delayed diagnoses and take appropriate managements, as well as the development of atherosclerosis in SLE patients, and timely intervention has a better prognosis.

Mechanistic insight into premature atherosclerosis and cardiovascular complications in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is associated with a significant risk of cardiovascular disease (CVD), which substantially increases disease mortality and morbidity. The overall mechanisms associated with the development of premature atherosclerosis and CVD in SLE remain unclear, but has been considered as a result of an intricate interplay between the profound immune dysregulation and traditional CVD risk factors. Aberrant systemic inflammation in SLE may lead to an abnormal lipid profile and dysfunction, which can further fuel the pro-atherosclerotic environment. The existence of a strong imbalance between endothelial damage and vascular repair/angiogenesis promotes vascular injury, which is the early step in the progression of atherosclerotic CVD. Profound innate and adaptive immune dysregulation, characterized by excessive type I interferon burden, aberrant macrophage, platelet and complements activation, neutrophil dysregulation and neutrophil extracellular traps formation, uncontrolled T cell activation, and excessive autoantibody production and immune complex formation, have been proposed to promote accelerated CVD in SLE. While designing targeted therapies to correct the dysregulated immune activation may be beneficial in the treatment of SLE-related CVD, much additional work is needed to determine how to translate these findings into clinical practice. Additionally, a number of biomarkers display diagnostic potentials in improving CVD risk stratification in SLE, further prospective studies will help understand which biomarker(s) will be the most impactful one(s) in assessing SLE-linked CVD. Continued efforts to identify novel mechanisms and to establish criteria for assessing CVD risk as well as predicting CVD progression are in great need to improve CVD outcomes in SLE.

Diverse Roles of NETosis in the Pathogenesis of Lupus

NETosis is a form of neutrophil cell death during which extracellular fibrillary structures composed of cytosolic and granule proteins assembled on scaffolds of decondensed chromatin, called neutrophil extracellular traps (NETs), are released. NETs normally contribute to host immune defense. Accumulating evidence implicates aberrant NET production and/or reduced NET clearance, along with alterations of molecules involved in NETosis pathway, in humans and animals with lupus. The extruded nuclear antigens released by NET are a source of autoantigens, which can contribute to the breakdown of self-tolerance in lupus. Excessive NET can also promote the production of pro-inflammatory cytokine interferon-α, elicit direct cytotoxic effect on various renal cells, and cause capillary necrosis and podocyte loss. Additionally, NET can induce endothelial-to-mesenchymal transdifferentiation, which can promote activated myofibroblasts leading to extracellular matrix production. Thus, aberrant NETosis can play diverse roles, including autoantibody production, inflammation, and tissue damage, at different stages of lupus pathogenesis. Evidence suggests that treatments currently used in lupus may reduce NETosis, suggesting a potential utility of targeting NETosis to treat lupus. In fact, several approaches are being experimented to therapeutically target pathways of NETosis. Future studies should precisely delineate distinct roles of NETosis at different stages of lupus pathogenesis in humans, which would offer a rational basis for NETosis-targeting treatments in the clinic.

Endothelial Dysfunction Induced by Extracellular Neutrophil Traps Plays Important Role in the Occurrence and Treatment of Extracellular Neutrophil Traps-Related Disease

Many articles have demonstrated that extracellular neutrophil traps (NETs) are often described as part of the antibacterial function. However, since the components of NETs are non-specific, excessive NETs usually cause inflammation and tissue damage. Endothelial dysfunction (ED) caused by NETs is the major focus of tissue damage, which is highly related to many inflammatory diseases. Therefore, this review summarizes the latest advances in the primary and secondary mechanisms between NETs and ED regarding inflammation as a mediator. Moreover, the detailed molecular mechanisms with emphasis on the disadvantages from NETs are elaborated: NETs can use its own enzymes, release particles as damage-associated molecular patterns (DAMPs) and activate the complement system to interact with endothelial cells (ECs), drive ECs damage and eventually aggravate inflammation. In view of the role of NETs-induced ED in different diseases, we also discussed possible molecular mechanisms and the treatments of NETs-related diseases.

The Causal Relationship Between Blood Lipids and Systemic Lupus Erythematosus Risk: A Bidirectional Two-Sample Mendelian Randomization Study

Background: Although observational studies have demonstrated that blood lipids were associated with systemic lupus erythematosus (SLE), the causality of this association remains elusive as traditional observational studies were prone to confounding and reverse causality biases. Here, this study attempted to reveal the potential causal link between SLE and the levels of four blood lipids (HDL cholesterol, LDL cholesterol, TG, and TC).

Methods: Bidirectional two-sample Mendelian randomization (MR) was employed to explore the unconfounded causal associations between the four blood lipids and SLE. In addition, regression-based Multivariate MR (MVMR) to quantify the possible mediation effects of blood lipids on SLE. After a rigorous evaluation of the quality of studies, the single-nucleotide polymorphisms (SNPs) associated with the four blood lipids were selected from the Global Lipids Genetic Consortium (GLGC) consisted of 188,577 individuals of European ancestry, and the SNPs related to SLE were selected from a large-scale genome-wide association study (GWAS) database named IEU GWAS. Subsequently, MR analyses were conducted with inverse-variance weighted (IVW), weighted median, weighted mode, simple mode, and MR-Egger regression. Sensitivity analyses were performed to verify whether heterogeneity and pleiotropy led to bias in the MR results.

Results: Bidirectional two-sample MR results demonstrated that there was no significant causal association between SLE and the four blood lipids (When setting SLE as outcome, HDL cholesterol and SLE, IVW OR: 1.32, 95% CI: 1.05∼1.66, p = 1.78E-02; LDL cholesterol and SLE, IVW OR: 1.26, 95% CI: 1.04∼1.53, p = 2.04E-02; TG and SLE, IVW OR: 1.04, 95% CI: 0.71∼1.51, p = 8.44E-01; TC and SLE, IVW OR: 1.07, 95% CI: 0.89∼1.29, p = 4.42E-01; When setting SLE as exposure, SLE and HDL cholesterol, IVW OR: 1.00, 95% CI: 0.99∼1.01, p = 9.51E-01; SLE and LDL cholesterol, IVW OR: 0.99, 95% CI: 0.98∼1.00, p = 3.14E-01; SLE and TG, IVW OR: 0.99, 95% CI: 0.98∼1.00, p = 1.30E-02; SLE and TC, IVW OR: 0.99, 95% CI: 0.98∼1.00, p = 1.56E-01). Our MVMR analysis also provided little evidence that genetically determined lipid traits were significantly associated with the risk of SLE (HDL cholesterol and SLE, p = 9.63E-02; LDL cholesterol and SLE, p = 9.63E-02; TG and SLE, p = 8.44E-01; TC and SLE, p = 4.42E-01).

Conclusion: In conclusion, these data provide evidence that genetic changes in lipid traits are not significantly associated with SLE risk in the European population.

Endothelial function and endothelial progenitor cells in systemic lupus erythematosus

The observations that traditional cardiovascular disease (CVD) risk factors fail to fully account for the excessive cardiovascular mortality in patients with systemic lupus erythematosus (SLE) compared with the general population have prompted in-depth investigations of non-traditional, SLE-related risk factors that contribute to cardiovascular complications in patients with SLE. Of the various perturbations of vascular physiology, endothelial dysfunction, which is believed to occur in the earliest step of atherosclerosis, has been extensively investigated for its contribution to CVD risk in SLE. Endothelial progenitor cells (EPCs), which play a crucial part in vascular repair, neovascularization and maintenance of endothelial function, are quantitatively and functionally reduced in patients with SLE. Yet, the lack of a unified definition of EPCs, standardization of the quantity and functional assessment of EPCs as well as endothelial function measurement pose challenges to the translation of endothelial function measurements and EPC levels into prognostic markers for CVD in patients with SLE. This Review discusses factors that contribute to CVD in SLE, with particular focus on how endothelial function and EPCs are evaluated currently, and how EPCs are quantitatively and functionally altered in patients with SLE. Potential strategies for the use of endothelial function measurements and EPC quantification as prognostic markers of CVD in patients with SLE, and the limitations of their prognostication potential, are also discussed.

Polymorphonuclear Neutrophils in Rheumatoid Arthritis and Systemic Lupus Erythematosus: More Complicated Than Anticipated

Polymorphonuclear neutrophils (PMN) are the most abundant leucocytes in the circulation in humans. They represent a heterogeneous population exerting diverse functions through several activities. Usually described as typical pro-inflammatory cells, immunomodulatory properties of PMNs have been reported. Among others, once activated and depending on the stimulus, PMNs expel neutrophil extracellular traps (NET) in the extracellular space. NETs are complexes made of DNA and granule proteins representing an innate immune mechanism fighting infections. Nevertheless, an excess of NET formation might be involved in the development of inflammatory or autoimmune responses. Systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) are two chronic, inflammatory, autoimmune diseases of unknown etiology and affecting mostly women. Several abnormal or non-classical functions of PMNs or PMN sub-populations have been described in SLE and RA. Particularly, NETs have been suggested to trigger pro-inflammatory responses by exposing pro-inflammatory mediators. Likewise, NETs may be the targets of autoantibodies or even might trigger the development of autoantibodies by exposing autoantigens. In the present review, we will summarize heterogeneous properties of human PMNs and we will discuss recent evidence linking PMNs and NETs to the pathogenesis of both SLE and RA.

Case Report: A case of recurrent thrombosis in pediatric antiphospholipid syndrome associated with pediatric onset systemic lupus

Systemic lupus erythematosus (SLE) is an autoimmune disease with multi-system involvement as the main manifestation, and has complex and diverse clinical features. Studies on large samples have revealed that SLE patients have a significantly increased risk of thrombotic events, which are also one of the important causes of morbidity and mortality in SLE patients. Antiphospholipid syndrome (APS) is a rare autoimmune disorder characterized by recurrent arterial and venous thrombosis, pregnancy-related complications, and the persistence of antiphospholipid antibodies at a 12-week interval. There are few reports about SLE coexisting with APS in children. This paper reported a school-age patient who started the disease with gross hematuria after bumping into the waist. The initial diagnosis of renal contusion was then confirmed by color Doppler ultrasound as renal vein and inferior vena cava embolism. She suddenly developed severe chest pain and dyspnea 3 days after hospitalization. And imaging supported pulmonary embolism with massive proteinuria, hypoalbuminemia, and hypercholesterolemia. The initial diagnosis was nephrotic syndrome (NS) with arteriovenous embolization, and popliteal vein embolism occurred again 5 years later, and she was thus diagnosed with SLE coexisting with APS. Afterwards, we discussed the possible mechanism and therapeutic strategies of SLE&APS that started with nephrotic syndrome, in order to achieve early identification and treatment of the disease and improve the prognosis of children.

Metabolic syndrome at baseline was not predictive to new-onset cardiovascular diseases in patients with systemic lupus erythematosus: A prospective observational registry

Objective: It has been established that metabolic syndrome is prevalent in patients with systemic lupus erythematosus (SLE). The objective of this study was to investigate the effect of metabolic syndrome at baseline on new-onset cardiovascular disease (CVD) in patients with SLE. Methods: The demographic and lupus-related clinical variables of 229 patients with SLE were collected from the Korean Lupus Network (KORNET) registry. Metabolic syndrome was defined by the modified National Cholesterol Education Program’s Adult Treatment Panel III (NCEP ATP III) criteria. Binary logistic regression analysis was applied to identify clinical variables including metabolic syndrome related to pre-existing CVD at the time of enrollment or new-onset CVD during 3 years of follow-up.

Results: Patients with pre-existing CVD at baseline had higher rates of metabolic syndrome than those without CVD in SLE ( p = .022), whereas there was no difference in the frequency of metabolic syndrome between patients with and without new-onset CVD. Logistic regression analysis revealed that metabolic syndrome and the number of its components were associated with pre-existing CVD, together with body mass index and hypertriglyceridemia. Metabolic syndrome at baseline and its components were not related with increased risk of new-onset CVD. On the contrary, anti-dsDNA antibody titer, anti-ds DNA positivity, and lower diastolic blood pressure increased the risk of new-onset CVD. Conclusion: This study demonstrated that metabolic syndrome at baseline was not predictive to new-onset CVD at 3 years of follow-up, although it was associated with pre-existing CVD in SLE.