New and emerging therapies for systemic lupus erythematosus

Systemic Lupus Erythematosus (SLE) and lupus nephritis treatment is still based on non-specific immune suppression despite the first biological therapy for the disease having been approved more than a decade ago. Intense basic and translational research has uncovered a multitude of pathways that are actively being evaluated as treatment targets in SLE and lupus nephritis, with two new medications receiving FDA approval in the last 3 years. Herein we provide an overview of targeted therapies for SLE including medications targeting the B lymphocyte compartment, intracellular signaling, co-stimulation, and finally the interferons and other cytokines.

Type I interferon blockade with anifrolumab in patients with systemic lupus erythematosus modulates key immunopathological pathways in a gene expression and proteomic analysis of two phase 3 trials

INTRODUCTION

Anifrolumab is a type I interferon (IFN) receptor 1 (IFNAR1) blocking antibody approved for treating patients with systemic lupus erythematosus (SLE). Here, we investigated the immunomodulatory mechanisms of anifrolumab using longitudinal transcriptomic and proteomic analyses of the 52-week, randomised, phase 3 TULIP-1 and TULIP-2 trials.

METHODS

Patients with moderate to severe SLE were enrolled in TULIP-1 and TULIP-2 and received intravenous anifrolumab or placebo alongside standard therapy. Whole-blood expression of 18 017 genes using genome-wide RNA sequencing (RNA-seq) (pooled TULIP; anifrolumab, n=244; placebo, n=258) and 184 plasma proteins using Olink and Simoa panels (TULIP-1; anifrolumab, n=124; placebo, n=132) were analysed. We compared treatment groups via gene set enrichment analysis using MetaBase pathway analysis, blood transcriptome modules, in silico deconvolution of RNA-seq and longitudinal linear mixed effect models for gene counts and protein levels.

RESULTS

Compared with placebo, anifrolumab modulated >2000 genes by week 24, with overlapping results at week 52, and 41 proteins by week 52. IFNAR1 blockade with anifrolumab downregulated multiple type I and II IFN-induced gene modules/pathways and type III IFN-λ protein levels, and impacted apoptosis-associated and neutrophil extracellular traps-(NET)osis-associated transcriptional pathways, innate cell activating chemokines and receptors, proinflammatory cytokines and B-cell activating cytokines. In silico deconvolution of RNA-seq data indicated an increase from baseline of mucosal-associated invariant and γδT cells and a decrease of monocytes following anifrolumab treatment.

DISCUSSION

Type I IFN blockade with anifrolumab modulated multiple inflammatory pathways downstream of type I IFN signalling, including apoptotic, innate and adaptive mechanisms that play key roles in SLE immunopathogenesis.

Vascular damage in systemic lupus erythematosus

Vascular disease is a major cause of morbidity and mortality in patients with systemic autoimmune diseases, particularly systemic lupus erythematosus (SLE). Although comorbid cardiovascular risk factors are frequently present in patients with SLE, they do not explain the high burden of premature vascular disease. Profound innate and adaptive immune dysregulation seems to be the primary driver of accelerated vascular damage in SLE. In particular, evidence suggests that dysregulation of type 1 interferon (IFN-I) and aberrant neutrophils have key roles in the pathogenesis of vascular damage. IFN-I promotes endothelial dysfunction directly via effects on endothelial cells and indirectly via priming of immune cells that contribute to vascular damage. SLE neutrophils are vasculopathic in part because of their increased ability to form immunostimulatory neutrophil extracellular traps. Despite improvements in clinical care, cardiovascular disease remains the leading cause of mortality among patients with SLE, and treatments that improve vascular outcomes are urgently needed. Improved understanding of the mechanisms of vascular injury in inflammatory conditions such as SLE could also have implications for common cardiovascular diseases, such as atherosclerosis and hypertension, and may ultimately lead to personalized therapeutic approaches to the prevention and treatment of this potentially fatal complication.

Clinical and Serologic Phenotyping and Damage Indices in Patients With Systemic Lupus Erythematosus With and Without Fibromyalgia

OBJECTIVE

Given fibromyalgia (FM) frequently co-occurs with autoimmune disease, this study was initiated to objectively evaluate FM in a multiracial/ethnic cohort of patients with systemic lupus erythematosus (SLE).

METHODS

Patients with SLE were screened for FM using the 2016 FM classification criteria during an in-person rheumatologist visit. We evaluated hybrid Safety of Estrogens in Lupus National Assessment (SELENA)-SLE Disease Activity Index (SLEDAI) scores, SLE classification criteria, and Systemic Lupus International Collaborating Clinics damage index. We compared patients with and without FM and if differences were present, compared patients with FM with patients with non-FM related chronic pain.

RESULTS

316 patients with SLE completed the FM questionnaire. 55 (17.4%) met criteria for FM. The racial composition of patients with FM differed from those without FM (P = 0.023), driven by fewer Asian patients having FM. There was no difference in SLE disease duration, SELENA-SLEDAI score, or active serologies. There was more active arthritis in the FM group (16.4%) versus the non-FM group (1.9%) (P < 0.001). The Widespread Pain Index and Symptom Severity Score did not correlate with degree of SLE activity (r = -0.016; 0.107) among patients with FM or non-FM chronic pain (r = 0.009; -0.024). Regarding criteria, patients with FM had less nephritis and more malar rash. Systemic Lupus International Collaborating Clinics damage index did not differ between groups.

CONCLUSION

Except for arthritis, patients with SLE with FM are not otherwise clinically or serologically distinguishable from those without FM, and Widespread Pain Index and Symptom Severity Score indices do not correlate with SLEDAI. These observations support the importance of further understanding the underlying biology of FM in SLE.

Type I Interferons induce endothelial destabilization in Systemic Lupus Erythematosus in a Tie2-dependent manner

Endothelial cell (EC) dysfunction is a hallmark of Systemic Lupus Erythematosus (SLE) and Tie2 is a receptor essential for vascular stability. Inflammatory processes promote inhibition of Tie2 homeostatic activation, driving vascular dysfunction. In this work we determined whether type I Interferons (IFN) induce Tie2 signalling-mediated endothelial dysfunction in patients with SLE. Serum levels of Angiopoietin (Ang)-1, Ang-2 and soluble (s)Tie1 in patients with SLE and healthy controls were measured by ELISA. Monocytes from patients with SLE and Human Umbilical Vein EC (HUVEC) were stimulated with IFN-α, IFN-β (1000 I.U.) or SLE serum (20%). mRNA and protein expression, phosphorylation and translocation were determined by quantitative PCR, ELISA, Western Blot, flow cytometry and confocal microscopy. Viability and angiogenic capacity were determined by calcein and tube formation assays. We found that sTie1 and Ang-2 serum levels were increased and Ang-1 decreased in patients with SLE and were associated with clinical characteristics. Type I IFN significantly decreased Ang-1 and increased Ang-2 in monocytes from patients with SLE. Type I IFN increased sTie1 and Ang-2 secretion and reduced Tie2 activation in HUVEC. Functionally, type I IFN significantly reduced EC viability and impaired angiogenesis in a Tie2 signalling-dependent manner. Finally, SLE serum increased Ang-2 and sTie1 secretion and significantly decreased tube formation. Importantly, Tie1 and IFNAR1 knockdown reversed these effects in tube formation. Overall, type I IFN play an important role in the stability of EC by inhibiting Tie2 signalling, suggesting that these processes may be implicated in the cardiovascular events observed in patients with SLE.

Type I Interferons in Autoimmunity: Implications in Clinical Phenotypes and Treatment Response

Type I interferon (IFN-I) is thought to play a role in many systemic autoimmune diseases. IFN-I pathway activation is associated with pathogenic features, including the presence of autoantibodies and clinical phenotypes such as more severe disease with increased disease activity and damage. We will review the role and potential drivers of IFN-I dysregulation in 5 prototypic autoimmune diseases: systemic lupus erythematosus, dermatomyositis, rheumatoid arthritis, primary Sjögren syndrome, and systemic sclerosis. We will also discuss current therapeutic strategies that directly or indirectly target the IFN-I system.

Clinical Pharmacokinetics, Pharmacodynamics, and Immunogenicity of Anifrolumab

The type I interferon (IFN) signaling pathway is implicated in the pathogenesis of systemic lupus erythematosus (SLE). Anifrolumab is a monoclonal antibody that targets the type I IFN receptor subunit 1. Anifrolumab is approved in several countries for patients with moderate to severe SLE receiving standard therapy. The approved dosing regimen of anifrolumab is a 300-mg dose administered intravenously every 4 weeks; this was initially based on the results of the Phase 2b MUSE and further confirmed in the Phase 3 TULIP-1 and TULIP-2 trials, in which anifrolumab 300-mg treatment was associated with clinically meaningful improvements in disease activity with an acceptable safety profile. There have been several published analyses of the pharmacokinetic and pharmacodynamic profile of anifrolumab, including a population-pharmacokinetic analysis of 5 clinical studies of healthy volunteers and patients with SLE, in which body weight and type I IFN gene expression were significant covariates identified for anifrolumab exposure and clearance. Additionally, the pooled Phase 3 SLE population has been used to evaluate how serum exposure may be related to clinical responses, safety risks, and pharmacodynamic effects of the 21-gene type I IFN gene signature (21-IFNGS). The relevance of 21-IFNGS with regard to clinical efficacy outcomes has also been analyzed. Herein, the clinical pharmacokinetics, pharmacodynamics, and immunogenicity of anifrolumab as well as results of population-pharmacokinetics and exposure-response analyses are reviewed.

Identification of key biomarkers associated with immune cells infiltration for myocardial injury in dermatomyositis by integrated bioinformatics analysis

BACKGROUND

Dermatomyositis (DM) is an acquired autoimmune disease that can cause damage to various organs, including the heart muscle. However, the mechanisms underlying myocardial injury in DM are not yet fully understood.

METHODS

In this study, we utilized publicly available datasets from the Gene Expression Omnibus (GEO) database to identify hub-genes that are enriched in the immune system process in DM and myocarditis. Weighted gene co-expression network analysis (WGCNA), differentially expressed genes (DEGs) analysis, protein-protein interaction (PPI), and gene ontology (GO) analysis were employed to identify these hub-genes. We then used the CIBERSORT method to analyze immune cell infiltration in skeletal muscle specimens of DM and myocardium specimens of myocarditis respectively. Correlation analysis was performed to investigate the relationship between key genes and infiltrating immune cells. Finally, we predicted regulatory miRNAs of hub-genes through miRNet and validated their expression in online datasets and clinical samples.

RESULTS

Using integrated bioinformatics analysis, we identified 10 and 5 hub-genes that were enriched in the immune system process in the database of DM and myocarditis respectively. The subsequent intersections between hub-genes were IFIT3, OAS3, ISG15, and RSAD2. We found M2 macrophages increased in DM and myocarditis compared to the healthy control, associating with the expression of IFIT3, OAS3, ISG15, and RSAD2 in DM and myocarditis positively. Gene function enrichment analysis (GSEA) showed that IFIT3, OAS3, ISG15, and RSAD2 were mainly enriched in type I interferon (IFN) signaling pathway, cellular response to type I interferon, and response to type I interferon. Finally, we verified that the expression of miR-146a-5p was significantly higher in the DM with myocardial injury than those without myocardial injury (p = 0.0009).

CONCLUSION

Our findings suggest that IFIT3, OAS3, ISG15, and RSAD2 may play crucial roles in the underlying mechanism of myocardial injury in DM. Serum miR-146a-5p could be a potential biomarker for myocardial injury in DM.

Urinary markers differentially associate with kidney inflammatory activity and chronicity measures in patients with lupus nephritis

OBJECTIVE

Lupus nephritis (LN) is diagnosed by biopsy, but longitudinal monitoring assessment methods are needed. Here, in this preliminary and hypothesis-generating study, we evaluate the potential for using urine proteomics as a non-invasive method to monitor disease activity and damage. Urinary biomarkers were identified and used to develop two novel algorithms that were used to predict LN activity and chronicity.

METHODS

Baseline urine samples were collected for four cohorts (healthy donors (HDs, n=18), LN (n=42), SLE (n=17) or non-LN kidney disease biopsy control (n=9)), and over 1 year for patients with LN (n=42). Baseline kidney biopsies were available for the LN (n=46) and biopsy control groups (n=9). High-throughput proteomics platforms were used to identify urinary analytes ≥1.5 SD from HD means, which were subjected to stepwise, univariate and multivariate logistic regression modelling to develop predictive algorithms for National Institutes of Health Activity Index (NIH-AI)/National Institutes of Health Chronicity Index (NIH-CI) scores. Kidney biopsies were analysed for macrophage and neutrophil markers using immunohistochemistry (IHC).

RESULTS

In total, 112 urine analytes were identified from LN, SLE and biopsy control patients as both quantifiable and overexpressed compared with HDs. Regression analysis identified proteins associated with the NIH-AI (n=30) and NIH-CI (n=26), with four analytes common to both groups, demonstrating a difference in the mechanisms associated with NIH-AI and NIH-CI. Pathway analysis of the NIH-AI and NIH-CI analytes identified granulocyte-associated and macrophage-associated pathways, and the presence of these cells was confirmed by IHC in kidney biopsies. Four markers each for the NIH-AI and NIH-CI were identified and used in the predictive algorithms. The NIH-AI algorithm sensitivity and specificity were both 93% with a false-positive rate (FPR) of 7%. The NIH-CI algorithm sensitivity was 88%, specificity 96% and FPR 4%. The accuracy for both models was 93%.

CONCLUSIONS

Longitudinal predictions suggested that patients with baseline NIH-AI scores of ≥8 were most sensitive to improvement over 6-12 months. Viable approaches such as this may enable the use of urine samples to monitor LN over time.

Anti-citrullinated histone monoclonal antibody CIT-013, a dual action therapeutic for neutrophil extracellular trap-associated autoimmune diseases

Neutrophil extracellular traps (NETs) contribute to the pathophysiology of multiple inflammatory and autoimmune diseases. Targeting the NETosis pathway has demonstrated significant therapeutic potency in various disease models. Here, we describe a first-in-class monoclonal antibody (CIT-013) with high affinity for citrullinated histones H2A and H4, which inhibits NETosis and reduces tissue NET burden in vivo with significant anti-inflammatory consequences. We provide a detailed understanding of the epitope selectivity of CIT-013. Detection of CIT-013 epitopes in rheumatoid arthritis (RA) synovium provides evidence that RA is an autoimmune disease with excessive citrullinated NETs that can be targeted by CIT-013. We show that CIT-013 acts upon the final stage of NETosis, binding to its chromatin epitopes when plasma membrane integrity is compromised to prevent NET release. Bivalency of CIT-013 is necessary for NETosis inhibition. In addition, we show that CIT-013 binding to NETs and netting neutrophils enhance their phagocytosis by macrophages in an Fc-dependent manner. This is confirmed using a murine neutrophilic airway inflammation model where a mouse variant of CIT-013 reduced tissue NET burden with significant anti-inflammatory consequences. CIT-013's therapeutic activity provides new insights for the development of NET antagonists and indicates the importance of a new emerging therapy for NET-driven diseases with unmet therapeutic needs.

Effects of Antirheumatic Treatment on Cell Cholesterol Efflux and Loading Capacity of Serum Lipoproteins in Spondylarthropathies

Spondyloarthropathies (SpA) are associated with increased cardiovascular risk. Among possible mechanisms is the dysfunction of serum lipoproteins in regulating cell cholesterol homeostasis. Cholesterol efflux capacity (CEC)-the atheroprotective ability of HDL (high density lipoproteins) to accept cholesterol from macrophages-might predict cardiovascular disease independently of HDL-cholesterol levels. We aimed at evaluating modifications of CEC and of the atherogenic cholesterol loading capacity (CLC) of serum lipoproteins in psoriatic arthritis (PsA) and ankylosing spondylitis (AS) following anti-rheumatic treatment. A total of 62 SpA patients (37 PsA and 25 AS) were evaluated before and after treatment with tumor necrosis factor inhibitor and/or methotrexate. CEC and CLC were measured by radioisotopic and fluorometric techniques, respectively. Endothelial function was assessed by finger plethysmography (Endopat). In the whole SpA group, total and HDL-cholesterol increased after treatment, while lipoprotein(a) decreased and CLC was unchanged. Treatment was associated with increased Scavenger Receptor class B type I (SR-BI)-mediated CEC in the AS group. SR-BI- and ABCG1-mediated CEC were negatively associated with inflammatory parameters and positively related to coffee consumption. SR-BI CEC and CLC were positively and negatively associated with endothelial function, respectively. Our pilot study suggests that anti-rheumatic treatment is associated with favorable modulation of lipoprotein quality and function in SpA, particularly in AS, in spite of the induced increase in total cholesterol levels. If confirmed in a larger population, this might represent an atheroprotective benefit beyond what is reflected by conventional serum lipid profile.

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.

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.

Serum extracellular traps associate with the activation of myeloid cells in SLE patients with the low level of anti-DNA antibodies

Neutrophil extracellular traps (NETs) are involved in systemic lupus erythematosus (SLE). We sought to cluster SLE patients based on serum NET levels. Serum NET levels were higher in SLE patients than healthy controls. Frequencies of pleuritis and myositis were increased in patients with high serum NET levels. Serum NET levels negatively correlated with anti-double stranded DNA (anti-dsDNA) antibody titers and C1q-binding immune complexes, but positively correlated with C-reactive protein (CRP) and monocyte counts. Neutrophil transcriptome analysis demonstrated no difference in NET-associated signatures, irrespective of serum NET levels, suggesting anti-dsDNA antibody-mediated clearance of NETs. In serum, NET levels were significantly correlated with myeloid cell-derived inflammatory molecules. Serum NET-based cluster analysis revealed 3 groups of patients based on serum NET and CRP levels, anti-dsDNA antibody titers, and monocyte count. Monocytes were consistently activated following NET-containing immune complex (NET-IC) stimulation. In conclusion, SLE patients with high serum NET levels had lower anti-dsDNA antibody titers and higher inflammatory responses. NET-IC-stimulated monocytes might associate with an inflammatory response characterized by elevated CRP levels. These findings can apply to precision medicine, as inflammatory processes, rather than antibody-dependent processes, can be targeted in specific subpopulations of SLE patients.

Transcriptomics and quantitative proteomics reveal changes after second stimulation of bone marrow-derived macrophages from lupus-prone MRL/lpr mice

Innate immune memory can cause the occurrence and exacerbation of autoimmune diseases, and it is as well as being strongly associated with the pathogenesis of systemic lupus erythematosus (SLE), however, the specific mechanism remains to be further studied. We learned that IFN-γ stimulation generated innate immune memory in bone marrow-derived macrophages (BMDMs) and activated memory interferon-stimulated genes (ISGs). This research used IFN-γ and lipopolysaccharide (LPS) to treat BMDMs with lupus-prone MRL/lpr mice and showed that particular memory ISGs were substantially elevated in prestimulated macrophages. In order to identify the differentially expressed genes (DEGs), researchers turned to RNA-seq. GO and KEGG analysis showed that up-regulated DEGs were enriched in defense and innate immune responses, and were related to the expression of pattern recognition receptors (PRRs)-related pathways in macrophages. TMT-based proteome analysis revealed differentially expressed proteins (DEPs) up-regulated in BMDMs were abundant in metabolic pathways such as glucose metabolism. Our study found that after the secondary stimulation of MRL/lpr mice, the expression of PRRs in innate immune cells was changed, and IFN-related pathways were activated to release a large number of ISGs to promote the secondary response. At the same time, related metabolic modes such as glycolysis were enhanced, and epigenetic changes may occur. Therefore, SLE is brought on, maintained, and worsened by a variety of factors that work together to produce innate immune memory.

Scoring personalized molecular portraits identify Systemic Lupus Erythematosus subtypes and predict individualized drug responses, symptomatology and disease progression

OBJECTIVES

Systemic Lupus Erythematosus is a complex autoimmune disease that leads to significant worsening of quality of life and mortality. Flares appear unpredictably during the disease course and therapies used are often only partially effective. These challenges are mainly due to the molecular heterogeneity of the disease, and in this context, personalized medicine-based approaches offer major promise. With this work we intended to advance in that direction by developing MyPROSLE, an omic-based analytical workflow for measuring the molecular portrait of individual patients to support clinicians in their therapeutic decisions.

METHODS

Immunological gene-modules were used to represent the transcriptome of the patients. A dysregulation score for each gene-module was calculated at the patient level based on averaged z-scores. Almost 6100 Lupus and 750 healthy samples were used to analyze the association among dysregulation scores, clinical manifestations, prognosis, flare and remission events and response to Tabalumab. Machine learning-based classification models were built to predict around 100 different clinical parameters based on personalized dysregulation scores.

RESULTS

MyPROSLE allows to molecularly summarize patients in 206 gene-modules, clustered into nine main lupus signatures. The combination of these modules revealed highly differentiated pathological mechanisms. We found that the dysregulation of certain gene-modules is strongly associated with specific clinical manifestations, the occurrence of relapses or the presence of long-term remission and drug response. Therefore, MyPROSLE may be used to accurately predict these clinical outcomes.

CONCLUSIONS

MyPROSLE (https://myprosle.genyo.es) allows molecular characterization of individual Lupus patients and it extracts key molecular information to support more precise therapeutic decisions.

Sustained glucocorticoid tapering in the phase 3 trials of anifrolumab: a post-hoc analysis of the TULIP-1 and TULIP-2 trials

OBJECTIVES

Glucocorticoid sparing is a key priority for SLE management. We evaluated the effects of sustained glucocorticoid tapering in patients with SLE.

METHODS

This was a post hoc analysis of the randomized, placebo-controlled, 52-week phase 3 TULIP-1 and TULIP-2 trials of anifrolumab (300 mg intravenously once every four weeks for 48 weeks) plus standard therapy in patients with moderate to severe SLE. In a cohort of patients receiving glucocorticoids (prednisone or equivalent) 10 mg or more per day at baseline, we assessed changes in glucocorticoid dosage, patient-reported outcomes (PROs) and safety. Outcome measures were compared between sustained glucocorticoid taper responders (7.5 mg or less per day by Week 40 sustained through Week 52) and non-responders, regardless of treatment group, and between patients receiving anifrolumab or placebo.

RESULTS

Among the 726 patients in the TULIP trials, 375 patients received glucocorticoids 10 mg or more per day at baseline, and of these, 155 (41%) patients were sustained glucocorticoid taper responders. Compared with non-responders (n = 220), sustained glucocorticoid taper responders reduced their mean cumulative glucocorticoid dose by 32%, improved PRO scores, reduced blood pressure, and experienced fewer serious adverse events. Sustained glucocorticoid tapering was achieved by 51% (96/190) of patients receiving anifrolumab versus 32% (59/185) receiving placebo. Compared with placebo, more anifrolumab-treated patients achieved both sustained glucocorticoid taper and reduced overall disease activity (38% [72/190] vs 23% [33/185]).

CONCLUSION

Sustained glucocorticoid tapering is associated with clinical benefits. Anifrolumab treatment has potential to reduce disease activity and glucocorticoid exposure, a key goal of SLE management.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT02446912 and NCT02446899.

Differentiating central nervous system demyelinating disorders: The role of clinical, laboratory, imaging characteristics and peripheral blood type I interferon activity

Objective: While multiple sclerosis (MS) is considered the cornerstone of autoimmune demyelinating CNS disorders, systemic autoimmune diseases (SADs) are important MS mimickers. We sought to explore whether distinct clinical, laboratory, and imaging characteristics along with quantitation of peripheral blood type I interferon (IFN) activity could aid in differentiating between them.

Methods: A total of 193 consecutive patients with imaging features suggesting the presence of CNS demyelinating disease with or without relevant clinical manifestations underwent full clinical, laboratory, and imaging evaluation, including testing for specific antibodies against 15 cellular antigens. Expression analysis of type I IFN-inducible genes (MX-1, IFIT-1, and IFI44) was performed by real-time PCR, and a type I IFN score, reflecting type I IFN peripheral activity, was calculated. After joint neurological/rheumatological evaluation and 1 year of follow-up, patients were classified into MS spectrum and CNS autoimmune disorders.

Results: While 66.3% (n = 128) of the patients were diagnosed with MS spectrum disorders (predominantly relapsing–remitting MS), 24.9% (n = 48) were included in the CNS autoimmune group, and out of those, one-fourth met the criteria for SAD (6.7% of the cohort, n = 13); the rest (18.1% of the cohort, n = 35), despite showing evidence of systemic autoimmunity, did not fulfill SAD criteria and comprised the “demyelinating disease with autoimmune features” (DAF) subgroup. Compared to the MS spectrum, CNS autoimmune patients were older, more frequently females, with increased rates of hypertension/hyperlipidemia, family history of autoimmunity, cortical dysfunction, anti-nuclear antibody titers ≥1/320, anticardiolipin IgM positivity, and atypical for MS magnetic resonance imaging lesions. Conversely, lower rates of infratentorial and callosal MRI lesions, CSF T2 oligoclonal bands, and IgG-index positivity were observed in CNS autoimmune patients. Patients fulfilling SAD criteria, but not the DAF group, had significantly higher peripheral blood type I IFN scores at baseline compared to MS spectrum [median (IQR)]: 50.18 (152.50) vs. −0.64 (6.75), p-value: 0.0001.

Conclusion: Our study suggests that underlying systemic autoimmunity is not uncommon in patients evaluated for possible CNS demyelination. Distinct clinical, imaging and laboratory characteristics can aid in early differentiation between MS and CNS-involving systemic autoimmunity allowing for optimal therapeutic strategies. Activated type I IFN pathway could represent a key mediator among MS-like-presenting SADs and therefore a potential therapeutic target.

Peroxisome proliferator activated receptor-γ agonist pioglitazone improves vascular and metabolic dysfunction in systemic lupus erythematosus

OBJECTIVES

Premature cardiovascular events in systemic lupus erythematosus (SLE) contribute to morbidity and mortality, with no effective preventive strategies described to date. Immune dysregulation and metabolic disturbances appear to play prominent roles in the induction of vascular disease in SLE. The peroxisome proliferator activated receptor-gamma agonist pioglitazone (PGZ suppresses vascular damage and immune dysregulation in murine lupus and improves endothelial dysfunction in other inflammatory diseases. We hypothesised that PGZ could improve vascular dysfunction and cardiometabolic parameters in SLE.

METHODS

Eighty SLE subjects with mild to severe disease activity were randomised to a sequence of PGZ followed by placebo for 3 months, or vice versa, in a double-blind, cross-over design with a 2-month wash-out period. Primary endpoints were parameters of endothelial function and arterial inflammation, measured by multimodal assessments. Additional outcome measures of disease activity, neutrophil dysregulation, metabolic disturbances and gene expression studies were performed.

RESULTS

Seventy-two subjects completed the study. PGZ was associated with a significant reduction in Cardio-Ankle Vascular Index (a measure of arterial stiffness) compared with placebo. Various metabolic parameters improved with PGZ, including insulin resistance and lipoprotein profiles. Circulating neutrophil extracellular trap levels also significantly decreased with PGZ compared with placebo. Most adverse events experienced while on PGZ were mild and resolved with reduction in PGZ dose.

CONCLUSION

PGZ was well tolerated and induced significant improvement in vascular stiffness and cardiometabolic parameters in SLE. The results suggest that PGZ should be further explored as a modulator of cardiovascular disease risk in SLE.

TRIAL REGISTRATION NUMBER

NCT02338999.

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.

Nonlinear Population Pharmacokinetics of Anifrolumab in Healthy Volunteers and Patients With Systemic Lupus Erythematosus

We characterized the population pharmacokinetics of anifrolumab, a type I interferon receptor–blocking antibody. Pharmacokinetic data were analyzed from the anifrolumab (intravenous [IV], every 4 weeks) arms from 5 clinical trials in patients with systemic lupus erythematosus (SLE) (n = 664) and healthy volunteers (n = 6). Population pharmacokinetic modeling was performed using a 2‐compartment model with parallel linear and nonlinear elimination pathways. The impact of covariates (demographics, interferon gene signature [IFNGS, high/low], disease characteristics, renal/hepatic function, SLE medications, and antidrug antibodies) on pharmacokinetics was evaluated. Time‐varying clearance (CL) was characterized using an empirical sigmoidal time‐dependent function. Anifrolumab exposure increased more than dose‐proportionally from 100 to 1000 mg IV every 4 weeks. Based on population pharmacokinetics modeling, the baseline median linear CL was 0.193 L/day in IFNGS‐high patients and 0.153 L/day in IFNGS‐low/healthy volunteers. After a year, median anifrolumab linear CL decreased by 8.4% from baseline. Body weight and IFNGS were significant pharmacokinetic covariates, whereas age, sex, race, disease activity, SLE medications, and presence of antidrug antibodies had no significant effect on anifrolumab pharmacokinetics. Anifrolumab at a concentration of 300 mg IV every 4 weeks was predicted to be below the lower limit of quantitation in 95% of patients ≈10 weeks after a single dose and ≈16 weeks after stopping dosing at steady state. To conclude, anifrolumab exhibited nonlinear pharmacokinetics and time‐varying linear CL; doses ≥300 mg IV every 4 weeks provided sustained anifrolumab concentrations. This study provides further evidence to support the use of anifrolumab 300 mg IV every 4 weeks in patients with moderate to severe SLE.

The Relationship between Anifrolumab Pharmacokinetics, Pharmacodynamics, and Efficacy in Patients With Moderate to Severe Systemic Lupus Erythematosus

This study aimed to elucidate the pharmacokinetic/pharmacodynamic and pharmacodynamic/efficacy relationships of anifrolumab, a type I interferon receptor antibody, in patients with moderate to severe systemic lupus erythematosus. Data were pooled from the randomized, 52‐week, placebo‐controlled TULIP‐1 and TULIP‐2 trials of intravenous anifrolumab (150 mg/300 mg, every 4 weeks for 48 weeks). Pharmacodynamic neutralization was measured with a 21‐gene type I interferon gene signature (21‐IFNGS) in patients with high IFNGS. The pharmacokinetic/pharmacodynamic relationship was analyzed graphically and modeled with a nonlinear mixed‐effects model. British Isles Lupus Assessment Group–based Composite Lupus Assessment (BICLA) response rates were compared across 21‐IFNGS neutralization quartiles. Overall, 819 patients received ≥1 dose of anifrolumab or placebo, of whom 676 were IFNGS high. Over 52 weeks, higher average anifrolumab serum concentrations were associated with increased median 21‐IFNGS neutralization, which was rapid and sustained with anifrolumab 300 mg (>80%, weeks 12‐52), lower and delayed with anifrolumab 150 mg (>50%, week 52), and minimal with placebo. The proportion of patients with week 24 anifrolumab trough concentration exceeding the IC₈₀ (3.88 μg/mL) was greater with anifrolumab 300 mg vs anifrolumab 150 mg (≈83% vs ≈27%), owing to the higher estimated median trough concentration (15.6 vs 0.2 μg/mL). BICLA response rates increased with 21‐IFNGS neutralization; more patients had a BICLA response in the highest vs lowest neutralization quartiles at week 52 (58.1% vs 37.6%). In conclusion, anifrolumab 300 mg every 4 weeks rapidly, substantially, and sustainably neutralized the 21‐IFNGS and was associated with clinical efficacy, supporting this dosing regimen in patients with systemic lupus erythematosus.

Anifrolumab efficacy and safety by type I interferon gene signature and clinical subgroups in patients with SLE: post hoc analysis of pooled data from two phase III trials

Objectives

To characterise the efficacy and safety of anifrolumab in patients with systemic lupus erythematosus (SLE) according to interferon gene signature (IFNGS), demographic and clinical subgroups.

Methods

We performed post hoc analyses of pooled data from the 52-week phase III TULIP-1/TULIP-2 placebo-controlled trials of intravenous anifrolumab in moderate-to-severe SLE. Outcomes were assessed in predefined subgroups: IFNGS (high/low), age, sex, body mass index, race, geographic region, age of onset, glucocorticoid use, disease activity and serological markers.

Results

In pooled data, patients received anifrolumab 300 mg (360/726) or placebo (366/726); 82.6% were IFNGS-high. IFNGS-high patients had greater baseline disease activity and were more likely to have abnormal serological markers versus IFNGS-low patients. In the total population, a greater proportion of patients treated with anifrolumab versus placebo achieved British Isles Lupus Assessment Group-based Composite Lupus Assessment (BICLA) response at week 52 (difference 16.6%; nominal p<0.001). BICLA response treatment differences with anifrolumab versus placebo were comparable to the total population across most predefined subgroups, including subgroups for baseline glucocorticoid dosage (<10/≥10 mg/day prednisone/equivalent) and for clinical disease activity (SLE Disease Activity Index 2000 score <10/≥10). Subgroups with larger treatment differences included IFNGS-high patients (18.2%), patients with abnormal baseline serological markers (23.1%) and Asian patients (29.2%). The safety profile of anifrolumab was similar across subgroups.

Conclusions

Overall, this study supports the consistent efficacy and safety of anifrolumab across a range of patients with moderate-to-severe SLE. In a few subgroups, small sample sizes limited conclusions from being drawn regarding the treatment benefit with anifrolumab.

Trial registration number

NCT02446912, NCT02446899.

Association of primary Sjögren’s syndrome with incident heart failure: a secondary analysis of health claims data in Taiwan

Objective:

Mounting evidence has demonstrated that various chronic inflammatory diseases are associated with incident heart failure (HF). However, there is scarce evidence about the association between primary Sjögren’s syndrome (pSS) and HF. We aimed to explore this association using a nationwide database in Taiwan.

Methods:

We selected patients with incident pSS and no history of HF. Using propensity score matching based on age, sex, cohort entry time, comorbidities, and concomitant medications, cohorts of patients with and without pSS (as controls) were created in a 1:1 ratio and the groups were compared. The cumulative incidence of HF was calculated using Kaplan–Meier estimation. Cox proportional hazard regression analysis was used to measure the hazard ratio (HR) of HF-related hospitalization for the pSS cohort compared with the comparison group.

Results:

A total of 16,466 pairs of patients with pSS and those without pSS were identified. The cumulative incidence of HF-related hospitalization at 3, 5, and 10 years in patients with pSS was 1.05%, 1.89%, and 4.33%, respectively. The risk of HF-related hospitalization was not higher in patients with pSS than in the general population (HR: 0.98, 95% confidence interval [CI]: 0.84–1.14). There was no difference in survival probability after the first episode of HF-related hospitalization between pSS and non-pSS groups.

Conclusion:

Our results suggest that distinct inflammatory spectrums in each chronic inflammatory disease might have differential impacts on cardiac function and subsequent risk of HF. Future studies are needed to elucidate the complex and diverse mechanisms of HF in various chronic autoimmune diseases.

Enhanced type I interferon signature induces neutrophil extracellular traps enriched in mitochondrial DNA in adult-onset Still's disease

Adult-onset Still's disease (AOSD) is a rare but clinically well-known auto-inflammatory disorder. Cytokine storm, the hallmark of AOSD, is mediated by neutrophil hyperactivation and enhanced neutrophil extracellular trap (NET) formation. Type I interferons (IFNs), having a primary role in the initiation of proinflammation responses, can induce subsequent inflammatory cytokine production. However, the role of type I IFNs in AOSD is unclear. Indeed, high levels of IFN-α and IFN-β expression are presented by AOSD patients. In this investigation, hierarchical unsupervised clustering was performed on IFN-α and IFN-β data to identify a cluster of AOSD patients who had a serious condition. Neutrophils from treatment-naïve active AOSD patients showed very strong enrichment in their IFN-α response, as shown by RNA-seq and confirmed by the IFN score. Whether IFN-α stimulates NET formation was also tested. IFN-α had the ability to form NETs that contained oxidized mitochondrial DNA (ox-mtDNA). Moreover, the JAK inhibitor could be used to dampen type I IFN-induced NET formation and eventually control ox-mtDNA release. Our results demonstrated the important roles of type I IFNs in the pathogenesis of AOSD through their promotion of NET formation, as characterized by the enhanced level of ox-mtDNA. The findings open up new avenues of research into therapeutic approaches for AOSD.

[Pharmacological actions of anifrolumab (Saphnelo®) and clinical trial results as a treatment for systemic lupus erythematosus]

Systemic lupus erythematosus (SLE) is an autoimmune disease which causes damaging inflammation in multiple organs via the accumulation of immune complexes. SLE pathogenesis is associated with type I interferons (IFNs), which are central and reflective of disease activity in SLE. Even before clinical development of disease, genetic and environmental contributions to IFN production lead to abnormal innate and adaptive immune activation. Through the Janus kinase-signal transducer and activator of transcription signaling pathway, IFN play a central role in the immunopathogenicity of SLE. Thus, IFN-blocking therapy may be used to regulate inflammation in individuals with SLE. Food and Drug Administration (FDA)-approved anifrolumab (Saphnelo^®), which is a human IgG1κ monoclonal antibody that binds to subunit 1 of the type I interferon receptor with high specificity and affinity, was also approved for the treatment of adult patients with moderate to severe SLE who are receiving standard therapy by Pharmaceuticals and Medical Device Agency (PMDA), in Japan in September 2021; anifrolumab is administered as an intravenous infusion, 300 mg over a 30-minute period, every 4 weeks. In this article, we reviewed the actions of type I IFN and anifrolumab as a treatment for SLE.

The Pathogenesis, Molecular Mechanisms, and Therapeutic Potential of the Interferon Pathway in Systemic Lupus Erythematosus and Other Autoimmune Diseases

Therapeutic success in treating patients with systemic lupus erythematosus (SLE) is limited by the multivariate disease etiology, multi-organ presentation, systemic involvement, and complex immunopathogenesis. Agents targeting B-cell differentiation and survival are not efficacious for all patients, indicating a need to target other inflammatory mediators. One such target is the type I interferon pathway. Type I interferons upregulate interferon gene signatures and mediate critical antiviral responses. Dysregulated type I interferon signaling is detectable in many patients with SLE and other autoimmune diseases, and the extent of this dysregulation is associated with disease severity, making type I interferons therapeutically tangible targets. The recent approval of the type I interferon-blocking antibody, anifrolumab, by the US Food and Drug Administration for the treatment of patients with SLE demonstrates the value of targeting this pathway. Nevertheless, the interferon pathway has pleiotropic biology, with multiple cellular targets and signaling components that are incompletely understood. Deconvoluting the complexity of the type I interferon pathway and its intersection with lupus disease pathology will be valuable for further development of targeted SLE therapeutics. This review summarizes the immune mediators of the interferon pathway, its association with disease pathogenesis, and therapeutic modalities targeting the dysregulated interferon pathway.

Cardiovascular Disease in Older Women

Cardiovascular disease is the major cause of death in women. Older women remain at risk for coronary artery disease/cardiovascular disease, but risk-modifying behavior can improve outcomes. Women have a different symptom profile and have been underdiagnosed and undertreated as compared with men. Although older women are underrepresented in trials, clinicians should be more attuned to the prevention, diagnosis, and treatment of cardiovascular disease in older women.

SLE: IFN-Rezeptor-Blockade könnte kardiovaskuläres Risiko senken

Patienten mit systemischem Lupus erythematodes (SLE) haben ein stark erhöhtes Risiko für kardiovaskuläre Komplikationen. Bei der Pathogenese spielen vermutlich Gefäßschäden durch eine Dysregulation von Neutrophilen und der Typ-I-Interferon (IFN)-Achse eine Rolle. Wissenschaftler haben nun untersucht, ob Anifrolumab, ein Typ-I-IFN-Rezeptor-blockierender Antikörper, die Bildung von sogenannten neutrophil extracellular traps (NET) reduzieren und weitere kardiometabolische Risikofaktoren modulieren kann.

Interferons in Systemic Lupus Erythematosus

Skewing of type I interferon (IFN) production and responses is a hallmark of systemic lupus erythematosus (SLE). Genetic and environmental contributions to IFN production lead to aberrant innate and adaptive immune activation even before clinical development of disease. Basic and translational research in this arena continues to identify contributions of IFNs to disease pathogenesis, and several promising therapeutic options for targeting of type I IFNs and their signaling pathways are in development for treatment of SLE patients.

Chronic inflammatory diseases and coronary heart disease: Insights from cardiovascular CT

Epidemiological and clinical studies have demonstrated a consistent relationship between increased systemic inflammation and increased risk of cardiovascular events. In chronic inflammatory states, traditional risk factors only partially account for the development of coronary artery disease (CAD) but underestimate total cardiovascular risk likely due to the residual risk of inflammation. Computed coronary tomography angiography (CCTA) may aid in risk stratification by noninvasively capturing early CAD, identifying high risk plaque morphology and quantifying plaque at baseline and in response to treatment. In this review, we focus on reviewing studies on subclinical atherosclerosis by CCTA in individuals with chronic inflammatory conditions including rheumatoid arthritis (RA), systemic lupus erythematous (SLE), human immunodeficiency virus (HIV) infection and psoriasis. We start with a brief review on the role of inflammation in atherosclerosis, highlight the utility of using CCTA to delineate vessel wall and plaque characteristics and discuss combining CCTA with laboratory studies and emerging technologies to complement traditional risk stratification in chronic inflammatory states.

Interferon lambda in inflammation and autoimmune rheumatic diseases

Interferons are potent antiviral cytokines that modulate immunity in response to infection or other danger signals. In addition to their antiviral functions, type I interferons (IFNα and IFNβ) are important in the pathogenesis of autoimmune diseases. Type III interferons (IFNλs) were initially described as a specialized system that inhibits viral replication at epithelial barrier surfaces while limiting inflammatory damage. However, evidence now suggests that type III interferons have complex effects on both innate and adaptive immune responses and might also be pathogenic in systemic autoimmune diseases. Concentrations of IFNλs are increased in blood and tissues in a number of autoimmune rheumatic diseases, including systemic lupus erythematosus, and are further associated with specific clinical and laboratory parameters. This Review is aimed at providing a critical evaluation of the current literature on IFNλ biology and how type III interferons might contribute to immune dysregulation and tissue damage in autoimmunity. The potential effects of type III interferons on treatment strategies for autoimmune rheumatic diseases, such as interferon blockade, are also considered.

Understanding Accelerated Atherosclerosis in Systemic Lupus Erythematosus: Toward Better Treatment and Prevention

Systemic lupus erythematosus (SLE) carries a significant risk of cardiovascular disease (CVD). The prevalence of premature CVD is especially noteworthy because it occurs in premenopausal women with SLE who would otherwise have very low rates of CVD. While traditional risk factors likely play a role in development of CVD in the setting of SLE, they do not fully explain the excess risk. The pathogenesis of CVD in SLE is not fully understood, but the inflammatory nature of SLE is believed to be a key factor in accelerating atherosclerosis. Systemic inflammation may lead to an abnormal lipid profile with elevated triglycerides, total cholesterol, and low-density lipoprotein cholesterol and dysfunctional high-density lipoprotein cholesterol. Additionally, the inflammatory milieu of SLE plasma promotes endothelial dysfunction and vascular injury, early steps in the progression of atherosclerotic CVD. Despite the overall headway that has been achieved in treating lupus, innovative therapeutics specifically targeting the progression of atherosclerosis within the lupus population are currently lacking. However, there have been advancements in the development of promising modalities for diagnosis of subclinical atherosclerosis and detection of high CVD risk patients. Due to the significant impact of CVD on morbidity and mortality, research addressing prevention and treatment of CVD in SLE needs to be prioritized. This review explores the intricate interplay of SLE-specific properties that contribute to atherosclerosis and CVD within this population, as well as screening methods and possible therapies.

Identification of a Novel Serum Proteomic Signature for Primary Sjögren's Syndrome

Context

Primary Sjögren's syndrome (pSS) is a complex heterogeneous autoimmune disease (AID) which can mimic rheumatoid arthritis (RA) or systemic lupus erythematosus (SLE). Our exploratory study investigated serum biomarkers that may discriminate pSS from RA and SLE.

Methods

Serum concentrations of 63 biomarkers involved in immune cell trafficking, inflammatory response, cellular movement, and cell-to-cell signaling were measured in AID patients, included prospectively into the study at the Montpellier University Hospital. A multivariate analysis by multiple logistic regression was performed, and discriminative power assessed using logistic regression adjusted on significant demographic factors.

Results

Among the 95 patients enrolled, 42 suffered from pSS, 28 from RA, and 25 from SLE. Statistical analysis showed that concentrations of BDNF (OR = 0.493 with 95% CI [0.273-0.891]; p = 0.0193) and I-TAC/CXCL11 (OR = 1.344 with 95% CI [1.027-1.76]; p = 0.0314) can significantly discriminate pSS from RA. Similarly, greater concentrations of sCD163 (OR = 0.803 with 95% CI [0.649-0.994]; p = 0.0436), Fractalkine/CX3CL1 (OR = 0.534 with 95% CI [0.287-0. 991]; p = 0.0466), MCP-1/CCL2 (OR = 0.839 with 95% CI [0.732-0.962]; p = 0.0121), and TNFa (OR = 0.479 with 95% CI [0.247-0.928]; p = 0.0292) were associated with SLE diagnosis compared to pSS. In addition, the combination of low concentrations of BDNF and Fractalkine/CX3CL1 was highly specific for pSS (specificity 96.2%; positive predictive value 80%) compared to RA and SLE, as well as the combination of high concentrations of I-TAC/CXCL11 and low concentrations of sCD163 (specificity 98.1%; positive predictive value 75%).

Conclusion

Our study highlights biomarkers potentially involved in pSS, RA, and SLE pathophysiology that could be useful for developing a pSS-specific diagnostic tool.

Bite of the wolf: innate immune responses propagate autoimmunity in lupus

The etiopathogenesis of systemic lupus erythematosus (SLE), a clinically heterogeneous multisystemic syndrome that derives its name from the initial characterization of facial lesions that resemble the bite of a wolf, is considered a complex, multifactorial interplay between underlying genetic susceptibility factors and the environment. Prominent pathogenic factors include the induction of aberrant cell death pathways coupled with defective cell death clearance mechanisms that promote excessive externalization of modified cellular and nuclear debris with subsequent loss of tolerance to a wide variety of autoantigens and innate and adaptive immune dysregulation. While abnormalities in adaptive immunity are well recognized and are key to the pathogenesis of SLE, recent findings have emphasized fundamental roles of the innate immune system in the initiation and propagation of autoimmunity and the development of organ damage in this disease. This Review focuses on recent discoveries regarding the role of components of the innate immune system, specifically neutrophils and interferons, in promoting various aspects of lupus pathogenesis, with potential implications for novel therapeutic strategies.