Environment and systemic lupus erythematosus: an overview

The SLE Conundrum: A Comprehensive Analysis of Pathogenesis, Recent Developments, and the Future of Therapeutic Interventions

Systemic lupus erythematosus (SLE) is a complex autoimmune disorder with multifactorial interactions among various susceptibility factors. Significant strides have been made in understanding the pathogenesis of SLE, leading to the development of targeted therapies and the exploration of alternative treatments. The approval of new therapies has expanded patient treatment options, and ongoing clinical trials promise to enhance the treatment landscape further. The future of SLE treatment lies in personalized, targeted therapies that minimize side effects and improve patient outcomes. This review comprehensively analyzes SLE's current status and prospects based on recent studies, patents, clinical trials, and formulations. Continued research and clinical trials are crucial to uncovering new therapeutic options and ultimately transforming the treatment landscape for SLE. With sustained efforts and advancements in medical science, we can offer a better quality of life and improved survival rates for SLE patients.

Therapeutic potential of Nelumbo nucifera Linn. in systemic lupus erythematosus: Network pharmacology and molecular modeling insights

BACKGROUND

Systemic lupus erythematosus is a chronic autoimmune inflammatory disease characterized by multiple symptoms. The phenolic acids and other flavonoids in Nelumbo nucifera have anti-oxidants, anti-inflammatory, and immunomodulatory activities that are essential for managing SLE through natural sources. This study employs network pharmacology to unveil the multi-target and multi-pathway mechanisms of Nelumbo nucifera as a complementary therapy. The findings are validated through molecular modeling, which includes molecular docking followed by a molecular dynamics study.

METHODS

Active compounds and targets of SLE were obtained from IMPPAT, KNApAcKFamily and SwissTargetPrediction databases. SLE-related targets were retrieved from GeneCards and OMIM databases. A protein-protein interaction (PPI) network was built to screen out the core targets using Cytoscape software. ShinyGO was used for GO and KEGG pathway enrichment analyses. Interactions between potential targets and active compounds were assessed by molecular docking and molecular dynamics simulation study.

RESULTS

In total, 12 active compounds and 1190 targets of N. nucifera's were identified. A network analysis of the PPI network revealed 10 core targets. GO and KEGG pathway enrichment analyses indicated that the effects of N. nucifera are mediated mainly by AGE-RAGE and other associated signalling pathways. Molecular docking indicated favourable binding affinities, particularly leucocianidol exhibiting less than -4.5 kcal/mol for all 10 targets. Subsequent molecular dynamics simulations of the leucocianidol-ESR1 complex aimed to elucidate the optimal binding complex's stability and flexibility.

CONCLUSIONS

Our study unveiled the potential therapeutic mechanism of N. nucifera in managing SLE. These findings provide insights for subsequent experimental validation and open up new avenues for further research in this field.

Navigating the landscape of SLE treatment: An expert viewpoint on the rationality and limitations of early biologic intervention

The approval of biologics, namely belimumab and anifrolumab, is being a game-changer in the approach to systemic lupus erythematosus (SLE). Currently we are indeed facing a revolution in the treatment paradigm of SLE, encompassing early combination of biologics with standard treatment in severe manifestations. In this regard, a lively discussion is taking place regarding the better positioning of biologics in the treatment of not necessarily severe, yet refractory and/or disfiguring manifestations which expose patients to worsened quality of life, reduced workability and enhanced risk of organ damage especially related to the misuse of glucocorticoids in the long run. Growing evidence supports the early use of targeted treatments in those patients, including the use of biologics before traditional immunosuppression, to achieve control of disease activity while minimizing treatment-related damage, privileging the timely use of therapeutics selectively impacting on key disease mechanisms in spite of a widespread immunosuppression. Patient profiling on a clinical and endotypical basis is helping in identifying better candidates to targeted drugs. More inflammatory organ involvement including persistent arthritis and infiltrating skin lesions seem likely to respond to anifrolumab, while B-mediated manifestations, a lively serology and a relapsing-remitting SLE course hint at a suitable role for belimumab. This seems at least partially connected to the inner effect of either drug, dampening inflammation through down-regulation of interferon signalling in the case of anifrolumab, while plastically modulating the B cell pool composition and function when coming to belimumab. Nevertheless, the mechanisms of both drugs are immunologically entangled at some extent, thereby requiring careful management especially in patients with longer disease history burdened with mixed manifestations. In this viewpoint we go over pros and cons of anticipatory biologic use in SLE, exploring features linked with better efficacy of either drug and the pathogenic and practical rationale for their positioning before traditional immunosuppression in moderate refractory SLE to be optimally managed in the 21st Century.

Monoclonal antibodies targeting interleukins for systemic lupus erythematosus: updates in early clinical drug development

INTRODUCTION

The advent of biological therapies has already revolutionized treatment strategies and disease course of several rheumatologic conditions, and monoclonal antibodies (mAbs) targeting cytokines and interleukins represent a considerable portion of this family of drugs. In systemic lupus erythematosus (SLE) dysregulation of different cytokine and interleukin-related pathways have been linked to disease development and perpetration, offering palatable therapeutic targets addressable via such mAbs.

AREAS COVERED

In this review, we provide an overview of the different biological therapies under development targeting cytokines and interleukins, with a focus on mAbs, while providing the rationale behind their choice as therapeutic targets and analyzing the scientific evidence linking them to SLE pathogenesis.

EXPERT OPINION

An unprecedented number of clinical trials on biological drugs targeting different immunological pathways are ongoing in SLE. Their success might allow us to tackle present challenges of SLE management, including the overuse of glucocorticoids in daily clinical practice, as well as SLE heterogenicity in treatment response among different individuals, hopefully paving the way toward precision medicine.

Modern Management of Pregnancy in Systemic Lupus Erythematosus: From Prenatal Counseling to Postpartum Support

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that predominantly affects women of childbearing age. Pregnancy in SLE patients poses unique challenges due to the potential impact on maternal and fetal outcomes. We provide an overview of the management of SLE during pregnancy, including preconception risk stratification and counseling, treatment, and disease activity monitoring. These assessments are critical to minimize maternal and fetal adverse events in pregnant patients with SLE. Disease flares, preeclampsia, antiphospholipid syndrome complications, and maternal mortality are the major risks for a woman with SLE during gestation. Timely treatment of SLE relapse, differentiation of preeclampsia from lupus nephritis, and tailored management for antiphospholipid syndrome are essential for a successful pregnancy. Fetal outcomes include neonatal lupus (NL), preterm birth, cesarean delivery, fetal growth restriction (FGR), and small-for-gestational-age (SGA) infants. We focused on NL, linked to maternal anti-Ro/SS-A and anti-La/SS-B antibodies, which can lead to various manifestations, particularly cardiac abnormalities, in newborns. While there is a common consensus regarding the preventive effect of hydroxychloroquine, the role of echocardiographic monitoring and fluorinated steroid treatment is still debated. Finally, close postpartum monitoring and counseling for subsequent pregnancies are crucial aspects of care.

The SLE-DAS provides an accurate and feasible flare tool in the clinical setting: a validation study

OBJECTIVE

To assess the criterion validity of the SLE disease activity score (SLE-DAS) flare tool and compare its performance in identifying flares against other instruments.

METHODS

Patients with SLE fulfilling SLE-DAS low disease activity at baseline were included from two academic lupus clinics. During follow-up, flares were identified by the senior attending clinician, applying the expert-consensus-based definition as gold-standard. The first clinical flare from flaring patients, and the first visit after baseline in patients without flares were analysed. In each no flare/flare visits, we assessed flares by SLE-DAS (score increase ≥1.72), classic-SELENA Flare Index (c-SELENA FI), revised-SELENA FI (r-SELENA FI), and SLEDAI-2K (score increase ≥4). We estimated the sensitivity, specificity, and Cohen's Kappa agreement of each flare tool against the gold-standard.

RESULTS

A total of 442 patients were included and followed-up for 22.9 (14.2) months. Incidence of flares was 8.19/100 patient-years, with 69 patients experiencing flares. The SLE-DAS identified 96.6% of the expert-defined flares implying a treatment change and classified 28.0% of those as moderate/severe. Sensitivity and specificity for the gold-standard flare definition were: SLE-DAS 97.1% and 97.3%, c-SELENA FI 88.4% and 98.1%, r-SELENA FI 88.4% and 96.8%, SLEDAI-2K 56.5% and 99.2%, respectively. Kappa coefficients of these instruments were 0.902 (95% CI: 0.847, 0.957), 0.870 (95% CI: 0.805, 0.935), 0.832 (95% CI: 0.761, 0.903), and 0.663 (95% CI: 0.557, 0.769), respectively. The number of flare misclassifications was lowest with the SLE-DAS, and highest with the SLEDAI-2K.

CONCLUSION

The SLE-DAS accurately identifies and categorizes flares as mild or moderate/severe. It is feasible and, thus, may help the physicians' treatment decisions in the clinical practice setting.

Controversies in in rheumatology and autoimmunity: Is CORA meeting a good educational tool to increase the scientific knowledge?

Rheumatology and Autoimmunity are closely related fields and are among the most exciting areas in Medicine. Many conditions once regarded as mysterious and incurable are better understood and managed nowadays. Part of the great interest in these subjects derives from the fact that many controversial issues have arisen due to the rapid progression of knowledge, which means they are debatable. Over the years, the Controversies in Rheumatology and Autoimmunity (CORA) meetings promoted critical discussions not as an end but as a tool to increase the scientific knowledge of Rheumatologists and Clinical Immunologists. Beyond pursuing knowledge, being critical means questioning our inveterate beliefs and evaluating new conjectures and hypotheses. Thus, the approach to the debates in Medicine should be done with an open mind and free from all prejudices. Freedom of thought and speech are the fundamental values of our University, as exemplified by the motto "Universa Universis Patavine Libertas" which means "Padua freedom is universal for everyone". Patavine libertas initially referred to freedom from political and religious power but also freedom in research and teaching. For these reasons, Galileo Galilei moved to Padua in 1592, where he spent the most prosperous years of his life before being accused of heresy by the catholic church. We aim for the CORA congress to be an open-minded forum where active participation and exchange of ideas are promoted without prejudice. This special Issue of Autoimmunity Reviews is devoted to some controversies debated during the 7th CORA conference held in Turin, Italy, on March 16-18, 2023. Here we will discuss controversial entities, the use of old and new drugs, and insights into the classification, assessment of disease activity, and management of rheumatic diseases.

When should targeted therapies be used in the treatment of lupus nephritis: Early in the disease course or in refractory patients?

Although the prognosis of lupus nephritis (LN) has improved over the last few decades, 5-20% of patients still progress to kidney failure. Hence, there is an unmet need to improve the management of LN. Two novel drugs, belimumab and voclosporin, have been recently approved for LN and obinutuzumab is in the late stage of development. In randomised controlled trials (RCTs), all these drugs, added to the standard-of-care, were more effective than standard-of-care alone in achieving renal response. Now the question is: should these new drugs be used early in the disease course or just in refractory patients? The main reasons supporting the early use are based on the RCTs that demonstrated benefits when combinatory regimen was initiated early in incident and relapsing patients leading to a higher proportion of patients to achieve renal response, hence reducing nephron loss and the risk of kidney failure. The main reasons supporting the use of the combinatory regimens primarily in relapsing/refractory patients acknowledge that many patients responded well even without add-on medications, allowing a more economic use of innovative and costly drugs. However, good predictors of renal response to standard-of-care are lacking and, thus, the decision of adding new treatments early or just in refractory or relapsing patients has to consider drug access, risks of over or undertreatment, and preservation of kidney function in high-risk individuals.

Systemic lupus erythematosus incidence and prevalence in a large population-based study in northeastern Italy

OBJECTIVES

We aimed at estimating the incidence and prevalence of SLE in northeastern Italy over the period 2012-20.

METHODS

A retrospective population-based study was conducted in Veneto Region (4.9 million people) using the population registry, an administrative health database where all residents are recorded. Between 2012 and 2020, SLE prevalence was defined by a healthcare co-payment exemption for SLE (national registry code 028) or any hospital diagnosis of SLE (International Classification of Disease , Ninth Revision, Clinical Modification 710.0), whichever came first. Incident SLE was defined from 2013 to 2020 to exclude prevalent cases. Standardized incidence and prevalence rates were reported by age and sex.

RESULTS

During the study period, we identified 4283 SLE patients (85% female), with 1092 incident cases. Across the study period, SLE standardized point prevalence increased from 63.5 (95% CI 61.2, 65.8) to 70.6 (95% CI 68.3, 73.0) per 100 000 residents, corresponding to an annual increment of 1.14% (P < 0.0001). The highest prevalence was observed in females aged 60-69 years. SLE incidence corresponded to 2.8 per 100 000 person-years (95% CI 2.6, 2.9), with an annual decline of 7.3% (P < 0.0001). Incidence was 5-fold higher in females (female-to-male incidence rate ratio: 5.00, 95% CI 4.25, 5.87; P < 0.0001), with a peak among women aged 30-39 years. At diagnosis, women were significantly younger (45 years, IQR 33-58) than men (52 years, IQR 38-64).

CONCLUSIONS

Over the last decade, SLE prevalence has increased, while incidence has stably declined. In view of the introduction of new high-cost drugs, a clear definition of the epidemiology of SLE is crucial for all healthcare stakeholders.

Mortality and causes of death in systemic lupus erythematosus over the last decade: Data from a large population-based study

OBJECTIVE

To assess mortality rates (MRs), standardized mortality ratios, and causes of death in systemic lupus erythematosus (SLE) in a population-based study.

METHODS

We analyzed linked administrative health databases of the Veneto Region (Italy, 4,900,000 residents). SLE was defined by any hospital diagnosis or healthcare copayment exemption for SLE. We analyzed mortality from January 1st, 2012, until December 31st, 2021. MRs per 1000 were stratified by year, sex, and age group. Standardized mortality ratios were derived by comparing MRs of the general regional population. Causes of death were coded using the ICD-10 coding system and they were grouped in: SLE, infectious diseases, cardiovascular diseases (CVD), cancer, or others.

RESULTS

Among 4283 SLE prevalent cases, 603 deaths occurred, corresponding to an average annual standardized MR of 18.6 per 1000 person/year (95% CI 17.0-20.2). Out of 1092 incident SLE patients, 90 died with a peak in the first year after diagnosis (MR 26.5 per 10,000 person/month). Standardized mortality ratio was 2.65 (95% CI 2.13-3.26) overall, and highest among younger patients (<45 years: 5.59, 95% CI 2.05-12.4). Five- and 8-year survival were 91% and 89%, respectively. About half of the deaths had CVD or cancer as underlying cause, whereas infections were less frequently reported.

CONCLUSIONS

Although the medium-term survival since diagnosis is good, SLE mortality is still higher than that of the general population, especially in youngest patients. Nowadays, CVD seems to be the major cause of deaths in SLE, whereas infections account for a low proportion of deaths, at least in Western countries.

Early and Late Response and Glucocorticoid-Sparing Effect of Belimumab in Patients with Systemic Lupus Erythematosus with Joint and Skin Manifestations: Results from the Belimumab in Real Life Setting Study-Joint and Skin (BeRLiSS-JS)

AIM

To assess the efficacy of belimumab in joint and skin manifestations in a nationwide cohort of patients with SLE.

METHODS

All patients with skin and joint involvement enrolled in the BeRLiSS cohort were considered. Belimumab (intravenous, 10 mg/kg) effectiveness in joint and skin manifestations was assessed by DAS28 and CLASI, respectively. Attainment and predictors of DAS28 remission (<2.6) and LDA (≥2.6, ≤3.2), CLASI = 0, 1, and improvement in DAS28 and CLASI indices ≥20%, ≥50%, and ≥70% were evaluated at 6, 12, 24, and 36 months.

RESULTS

DAS28 < 2.6 was achieved by 46%, 57%, and 71% of patients at 6, 12, and 24 months, respectively. CLASI = 0 was achieved by 36%, 48%, and 62% of patients at 6, 12, and 24 months, respectively. Belimumab showed a glucocorticoid-sparing effect, being glucocorticoid-free at 8.5%, 15.4%, 25.6%, and 31.6% of patients at 6, 12, 24, and 36 months, respectively. Patients achieving DAS-LDA and CLASI-50 at 6 months had a higher probability of remission at 12 months compared with those who did not (p = 0.034 and p = 0.028, respectively).

CONCLUSIONS

Belimumab led to clinical improvement in a significant proportion of patients with joint or skin involvement in a real-life setting and was associated with a glucocorticoid-sparing effect. A significant proportion of patients with a partial response at 6 months achieved remission later on during follow-up.

Biochemical Studies of Systemic Lupus Erythematosus-Associated Mutations in Nonreceptor Tyrosine Kinases Ack1 and Brk

Tyrosine kinases (TKs) play essential roles in signaling processes that regulate cell survival, migration, and proliferation. Dysregulation of tyrosine kinases underlies many disorders, including cancer, cardiovascular and developmental diseases, as well as pathologies of the immune system. Ack1 and Brk are nonreceptor tyrosine kinases (NRTKs) best known for their roles in cancer. Here, we have biochemically characterized novel Ack1 and Brk mutations identified in patients with systemic lupus erythematosus (SLE). These mutations are the first SLE-linked polymorphisms found among NRTKs. We show that two of the mutants are catalytically inactive, while the other three have reduced activity. To understand the structural changes associated with the loss-of-function phenotype, we solved the crystal structure of one of the Ack1 kinase mutants, K161Q. Furthermore, two of the mutated residues (Ack1 A156 and K161) critical for catalytic activity are highly conserved among other TKs, and their substitution in other members of the kinase family could have implications in cancer. In contrast to canonical gain-of-function mutations in TKs observed in many cancers, we report loss-of-function mutations in Ack1 and Brk, highlighting the complexity of TK involvement in human diseases.

Gene Polymorphism of XRCC1 in Systemic Lupus Erythematous

Introduction:

There are debates about the role of the X-ray repair cross-complementation group 1 (XRCC1) Arg399Gln gene in the pathogenesis of Systemic Lupus Erythematosus (SLE).

Methods:

The study was a case-control study carried out on 100 recently diagnosed SLE patients compared to 100 control subjects. The study of XRCC1 Arg399Gln polymorphism was performed by a polymerase chain reaction and restriction fragment length polymorphism.

Results and Discussion:

A higher frequency of ‘G’ allele in SLE (38.5%) versus control (32%) was noticed; however, this difference was not statistically significant (p = 0.174). Besides, a slightly higher frequency of G/G genotype was found in SLE (22%) vs. control (12%); again, this difference was not statistically significant (p = 0.157). A statistically significantly higher proportion of arthritis, serositis, and thrombocytopenia was observed in the A/A genotype (p = 0.010, 0.032, and 0.036, respectively). Furthermore, we noticed a statistically significant lower hemoglobin level in G/G genotype (p = 0.027). Otherwise, there was no statistically significant difference between the three genotypes regarding other parameters: photosensitivity, malar rash, oral ulceration, ANA, anti-dsDNA antibody, anemia, leucopenia, neurologic manifestations, and all lab parameters except hemoglobin level. Similar results were reported previously.

According to genotype, in the study of Clinical and laboratory parameters in SLE patients, a statistically significantly higher proportion of arthritis, serositis, and thrombocytopenia was observed in the A/A genotype (p =0 .01, 0.032, and 0.036 respectively). Furthermore, we noticed a statistically significant lower hemoglobin level in G/G genotype (p = 0.027). These findings suggest a pathogenic connection between the seriousness of the defective DNA repair and the autoimmune severity; such connection is consistent with that found in several murine models. Additionally, negative regulation of the genes encoding the proteins involved in the NER pathway in SLE patients, specifically and XPC, has been found previously.

Conclusion:

The present study highlights the higher insignificant increase of G allele and GG genotype of XRCC1 399 gene in patients with SLE compared to healthy control. This increase was significantly associated with anemia in patients, which may reflect the aggravation of environmental risk factors to SLE associated with the reduced repair of DNA. Further longitudinal studies are required to validate the present findings.

Gene XRCC1Arg399Gln polymorphism and its genotype variations: clinical associations in Egyptian systemic lupus erythematosus patients

Background

Impaired deoxyribonucleic acid (DNA) repair may induce an autoimmune response in susceptible individuals. The association between DNA repair gene XRCC1 Arg399Gln gene polymorphism and susceptibility of systemic lupus erythematosus (SLE) is controversial. This study aimed to detect the association of XRCC1 Arg399Gln gene polymorphism with SLE and its clinical manifestations in the Egyptian population.

Results

A significant association was found between weight loss and genotype GG (P = 0.048); however, genotype AG was significantly associated with high serum creatinine and low C3 level (P = 0.039, P = 0.009, respectively). On the other hand, there was no significant difference between patients and controls regarding genotype and allele frequency.

Conclusions

An association was found between weight loss, high serum creatinine, and low C3 level and genotypes of XRCC1 Arg 399 Gln gene polymorphism.

Mechanistic Paradigms of Natural Plant Metabolites as Remedial Candidates for Systemic Lupus Erythromatosus

Systemic lupus erythematosus (SLE) is a complex autoimmune disorder involving a dysregulated immune response which ultimately leads to multiple organ failure. Several immunological and cellular checkpoints are available as drug targets. However, the available chemosynthetic drugs such as non-steroidal anti-inflammatory drugs and corticosteroids provide limited therapy with extreme toxicities. Moreover, the disease heterogeneity in SLE is very difficult to manage by a single drug component. Hence, it is imperative to utilize the holistic capabilities of natural plant products as immunomodulators and intracellular signaling regulators, thereby providing an auxiliary option of treatment. Additionally, the herbal drugs also serve as symptomatic relief providers, thereby serving as a prophylactic remedy in case of cerebrovascular, hepatic, nephropathological, hematological, cardiopulmonary, mucocutaneous and musculoskeletal manifestations of SLE. The present review attempts to showcase the current state of knowledge regarding the utility of plant-derived phyto-metabolites with their probable mechanistic roles in treating SLE, by means of targeting the signaling cascade, proinflammatory cytokine production and B-T cell co-stimulation. It is hoped that further preclinical and clinical studies will be embarked upon in order to understand the underlying therapeutic and mechanistic aspects of these medicinal herbs.

Contribution of mouse models in our understanding of lupus

Laboratory animal models are beneficial when they recapitulate all or just some of the clinical and immunological manifestations of the disease. Various animals such as cats, rats, dogs, hamsters, guinea pigs, rabbits, horses, minks, pigs, and primates have been described lupus-like phenotype. However, a mouse has remained the preferable animal for scientific investigations as a result of their reduced lifespan, easy reproduction, markedly low costs, public acceptance, ease of genetic management, and the probability to stay under standardized conditions. It is highly challenging to establish a mouse model with all features of lupus because of the difficulty and the heterogeneity of the clinical features in systemic lupus erythematous (SLE). Additionally, due to the multiple differences between the mouse and human immune system, the direct translation usually fails. Each mouse model has specific characteristics and shares many subsets of aspects with the disease observed in humans, which gives researchers a tool to select their particular needs. Over 50 years, many mice models have been developed and used to dissect the pathogenesis of lupus, also to test novel drugs and therapies. In general, mice models that contribute considerably in SLE understanding can be divided into four groups: Spontaneous models, induced models, genetically modified models, along with humanizing mouse models that are the link between the mouse and human immune system. In this updated review, we will present what has been learned from different lupus mice models and how these models have contributed to a better understanding of lupus pathogenesis and treatment.

Cross-Talk between Mitochondrial Dysfunction-Provoked Oxidative Stress and Aberrant Noncoding RNA Expression in the Pathogenesis and Pathophysiology of SLE

Systemic lupus erythematosus (SLE) is a prototype of systemic autoimmune disease involving almost every organ. Polygenic predisposition and complicated epigenetic regulations are the upstream factors to elicit its development. Mitochondrial dysfunction-provoked oxidative stress may also play a crucial role in it. Classical epigenetic regulations of gene expression may include DNA methylation/acetylation and histone modification. Recent investigations have revealed that intracellular and extracellular (exosomal) noncoding RNAs (ncRNAs), including microRNAs (miRs), and long noncoding RNAs (lncRNAs), are the key molecules for post-transcriptional regulation of messenger (m)RNA expression. Oxidative and nitrosative stresses originating from mitochondrial dysfunctions could become the pathological biosignatures for increased cell apoptosis/necrosis, nonhyperglycemic metabolic syndrome, multiple neoantigen formation, and immune dysregulation in patients with SLE. Recently, many authors noted that the cross-talk between oxidative stress and ncRNAs can trigger and perpetuate autoimmune reactions in patients with SLE. Intracellular interactions between miR and lncRNAs as well as extracellular exosomal ncRNA communication to and fro between remote cells/tissues via plasma or other body fluids also occur in the body. The urinary exosomal ncRNAs can now represent biosignatures for lupus nephritis. Herein, we’ll briefly review and discuss the cross-talk between excessive oxidative/nitrosative stress induced by mitochondrial dysfunction in tissues/cells and ncRNAs, as well as the prospect of antioxidant therapy in patients with SLE.

Molecular and Cellular Bases of Immunosenescence, Inflammation, and Cardiovascular Complications Mimicking "Inflammaging" in Patients with Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is an archetype of systemic autoimmune disease, characterized by the presence of diverse autoantibodies and chronic inflammation. There are multiple factors involved in lupus pathogenesis, including genetic/epigenetic predisposition, sexual hormone imbalance, environmental stimulants, mental/psychological stresses, and undefined events. Recently, many authors noted that "inflammaging", consisting of immunosenescence and inflammation, is a common feature in aging people and patients with SLE. It is conceivable that chronic oxidative stresses originating from mitochondrial dysfunction, defective bioenergetics, abnormal immunometabolism, and premature telomere erosion may accelerate immune cell senescence in patients with SLE. The mitochondrial dysfunctions in SLE have been extensively investigated in recent years. The molecular basis of normoglycemic metabolic syndrome has been found to be relevant to the production of advanced glycosylated and nitrosative end products. Besides, immunosenescence, autoimmunity, endothelial cell damage, and decreased tissue regeneration could be the results of premature telomere erosion in patients with SLE. Herein, the molecular and cellular bases of inflammaging and cardiovascular complications in SLE patients will be extensively reviewed from the aspects of mitochondrial dysfunctions, abnormal bioenergetics/immunometabolism, and telomere/telomerase disequilibrium.

TREX1 D18N mice fail to process erythroblast DNA resulting in inflammation and dysfunctional erythropoiesis

Anaemia is commonly observed in chronic inflammatory conditions, including systemic lupus erythematosus (SLE), where ∼50% of patients display clinical signs of anaemia. Mutation at the aspartate residue 18 of the three prime repair exonuclease 1 (TREX1) gene causes a monogenic form of cutaneous lupus in humans and the genetically precise TREX1 D18N mice recapitulate a lupus-like disease. TREX1 degrades single- and double-stranded DNA (dsDNA), and the link between failed DNA degradation by nucleases, including nucleoside-diphosphate kinases (NM23H1/H2) and Deoxyribonuclease II (DNase II), and anaemia prompted our studies to investigate whether TREX1 dysfunction contributes to anaemia. Utilizing the TREX1 D18N mice we demonstrate that (1) TREX1 mutant mice develop normocytic normochromic anaemia and (2) TREX1 exonuclease participates in the degradation of DNA originating from erythroblast nuclei during definitive erythropoiesis. Gene expression, hematocrit, hemoglobin, immunohistochemistry (IHC) and flow cytometry were used to quantify dysfunctional erythropoiesis. An altered response to induced anaemia in the TREX1 D18N mice was determined through IHC, flow cytometry, and interferon-stimulated gene (ISG) expression analysis of the liver, spleen and erythroblastic islands (EBIs). IHC, flow cytometry, and ISG expression studies were performed in vitro to determine the role of TREX1 in the degradation of erythroblast DNA within EBIs. The TREX1 D18N mice exhibit altered erythropoiesis including a 20% reduction in hematocrit, 10-20 fold increased erythropoietic gene expression levels in the spleen and phenotypic signs of normocytic normochromic anaemia. Anaemia in TREX1 D18N mice is accompanied by increased erythropoietin (Epo), normal hepcidin levels and the TREX1 D18N mice display an inappropriate response to anaemic challenge. Enhanced ISG expression results from failed processing and subsequent sensing of undegraded erythroblast DNA in EBIs. TREX1 participates in the degradation of erythroblast DNA in the EBI and TREX1 D18N mice exhibit a normocytic normochromic anaemia.

RETRACTED: Bach2 regulates aberrant activation of B cell in systemic lupus erythematosus and can be negatively regulated by BCR-ABL/PI3K

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). The article has been retracted at the request of the Editor-in-Chief and the authors. The journal is retracting this paper after the authors reached out to the journal with a statement that several images contained duplications from another published paper. Part of the panels in Figure 1D and Figure 4D are duplications of panels in Figure 7 of Wang et al., Int J Mol Sci (2016), DOI: 10.3390/ijms17060969. The β-actin panel in Figure 2E is same as the α-tubulin panel in Figure 4B. In addition, the corresponding author informed the journal that “there were serious conflicts of personal interest, part of co-authors of this paper were not involved in the study and not aware of the submission, and they did not authorize their names to appear in the article”.

Immune responses to an early lytic cytomegalovirus antigen in systemic lupus erythematosus patients: T-cell responses, cytokine secretions and antibody status

We investigated immune responses to a lytic cytomegalovirus antigen (CMVpp52), and to a lytic human herpes virus (HHV) 6 antigen (HHV6p41), in systemic lupus erythematosus (SLE) patients and healthy controls (HCs), in order to clarify if the previously established impaired responses to Epstein-Barr virus (EBV) in SLE patients is a general defect in their responses against (all) HHVs. Multiplex Luminex technology results showed a normal induction of five quantified cytokines (interferon γ, interleukin(IL)12, IL17, IL10, and tumor necrosis factor α) in SLE patients compared to HCs upon stimulation with CMVpp52 and HHV6p41. However, flow cytometric results showed a reduced upregulation of the activation marker CD69 on T-cells from SLE patients (n = 17) compared to HCs (n = 17) upon stimulation with CMVpp52, indicating limited or defective CMVpp52-specific T-cells and/or poor antigen-presentation in SLE patients, and thereby possibly decreased control of the CMV infection. In conclusion, the dysfunctional immune response against EBV previously established in SLE patients does not seem to apply to the same degree regarding the immune responses against CMV or HHV6. Results designate that the main contributing HHV agent in development or exacerbation of SLE (in genetically predisposed individuals) is the previously determined uncontrolled EBV infection, and to a lesser extent CMV infection, and probably with no involvement of HHV6 infection.

MiRNA and mRNA Profiling in Systemic Lupus Reveals a Novel Set of Cytokine - Related miRNAs and their Target Genes in Cases With and Without Renal Involvement

BACKGROUND/AIMS

MiRNAs transpire as promising elements in molecular medicine for the identification of new diagnostic, prognostic and targeting therapeutic biomarkers. This study consisted of four steps: First, to investigate one or a group of specific diagnostic miRNAs for Systemic Lupus Erythematosus (SLE) disease in patients with and without renal involvement, second, to identify cytokines genes' expression profiling, third, comparing the profiles with related amounts in the serum and finally, to study target-gene-mediated functional roles of miRNAs, which have been correlated to disease development and progression.

METHODS

In order to use in microarray assays total RNA and miRNAs were isolated from blood and serum samples that were obtained from 16 SLE patients (9 with renal involvement and 7 without renal involvement). Taking coexistence of factors such as hypocomplementemia, positive ANA and anti-DNA into account, obtained data were processed. For each differentially expressed miRNA, potential target genes were predicted by microRNAorg, TargetScan and PITA prediction tools. Obtained mRNA profiling data were interrogated for the target genes. MiRNA and mRNA microarray results were confirmed by QRT-PCR. Finally, the amounts of cytokines were measured by multiplex ELISA method.

RESULTS

The results of study showed that among differentially expressed miRNAs in SLE patients with renal involvement compared to those without renal involvement, hsa-miR-766-3p, may play pivotal roles in PI3K-AKT-mTOR pathway. In addition according to the obtained data it is suggested that blood-borne proinflammatory cytokines such as IL-4, IL-6 and TNF-α alongside with disease stage and severity may contribute to this differential expression of these miRNA which may be leading to insulin resistance. Finally, hsa-miR-621, which was differentially expressed in hypertensive SLE patients without renal involvement and a positive ANA test with its predicted target gene "Kallikrein-related peptidase 9" may play a role in the pathophysiology of hypertension in SLE.

CONCLUSIONS

We reported some human miRNAs which were differentially expressed in SLE patients according to disease activity and renal involvement. Larger studies are necessary to confirm our findings and detect further biomarkers.

Genetics of Lupus Nephritis: Clinical Implications

Systemic lupus erythematosus is a heterogeneous autoimmune disease marked by the presence of pathogenic autoantibodies, immune dysregulation, and chronic inflammation that may lead to increased morbidity and early mortality from end-organ damage. More than half of all systemic lupus erythematosus patients will develop lupus nephritis. Genetic-association studies have identified more than 50 polymorphisms that contribute to lupus nephritis pathogenesis, including genetic variants associated with altered programmed cell death and defective immune clearance of programmed cell death debris. These variants may support the generation of autoantibody-containing immune complexes that contribute to lupus nephritis. Genetic variants associated with lupus nephritis also affect the initial phase of innate immunity and the amplifying, adaptive phase of the immune response. Finally, genetic variants associated with the kidney-specific effector response may influence end-organ damage and the progression to end-stage renal disease and death. This review discusses genetic insights of key pathogenic processes and pathways that may lead to lupus nephritis, as well as the clinical implications of these findings as they apply to recent advances in biologic therapies.

Chloroquine treatment reduces the number of cutaneous HLA-DR+ and CD1a+ cells in patients with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that can be exacerbated by exposure to ultraviolet radiation (UVR). The number and phenotype of antigen presenting cells in the skin play a role in cutaneous immune response generation. Although antimalarials are widely used in SLE treatment, their mode of action is not completely elucidated. The aim of our study was to determine the effect of chloroquine treatment on HLA-DR+ and CD1a+ cell number in locally irradiated (three minimal erythema doses of UVB) and normal appearing skin in SLE patients and healthy subjects. A significantly higher number of HLA-DR+ and CD1a+ cells were found in both locations in SLE patients compared with controls. Following three months of daily chloroquine treatment (250 mg), the HLA-DR+ and CD1a+ cell counts were significantly reduced in both irradiated and unirradiated sites of SLE patients, although still higher than in controls. Chloroquine treatment reduces the number of antigen presenting cells in the skin of SLE patients, and this effect may explain the antimalarials beneficial immunoregulatory and anti-inflammatory properties.

The involvement of T regulatory lymphocytes in a cohort of lupus nephritis patients: a pilot study

T regulator lymphocytes (Tregs) play a key role in the maintenance of immune tolerance and in the development of autoimmune diseases. Expression of Foxp3 is specific for Tregs, and can be used for the identification of these cells. This study investigated the variations of Tregs Foxp3+ in the kidney biopsies inflammatory infiltrate of different lupus nephritis classes compared to that of ANCA glomerulonephritis, acute tubulointerstitial nephritis and nephroangiosclerosis. Sections of paraffin-embedded tissue have been stained by immunohistochemistry with anti-CD3 and anti-FoxP3 antibodies. We find that the ratio of FoxP3+/CD3+ cells is significantly lower in patients with lupus nephritis class IV and in patients with vasculitides than in the course of nephroangiosclerosis, tubulointerstitial nephritis and lupus nephritis class V. The data presented herein demonstrate a decrease of FoxP3+ Treg cells in the inflammatory infiltrate of lupus nephritis, particularly during the most active phases of lupus nephritis, as observed in the course of a IV class nephritis.

STING Negatively Regulates Double-Stranded DNA-Activated JAK1-STAT1 Signaling via SHP-1/2 in B Cells

Recognition of cytosolic DNA initiates a series of innate immune responses by inducing IFN-I production and subsequent triggering JAK1-STAT1 signaling which plays critical roles in the pathogenesis of infection, inflammation and autoimmune diseases through promoting B cell activation and antibody responses. The stimulator of interferon genes protein (STING) has been demonstrated to be a critical hub of type I IFN induction in cytosolic DNA-sensing pathways. However, it still remains unknown whether cytosolic DNA can directly activate the JAK1-STAT1 signaling or not. And the role of STING is also unclear in this response. In the present study, we found that dsDNA directly triggered the JAK1-STAT1 signaling by inducing phosphorylation of the Lyn kinase. Moreover, this response is not dependent on type I IFN receptors. Interestingly, STING could inhibit dsDNA-triggered activation of JAK1-STAT1 signaling by inducing SHP-1 and SHP-2 phosphorylation. In addition, compared with normal B cells, the expression of STING was significantly lower and the phosphorylation level of JAK1 was significantly higher in B cells from MRL/lpr lupus-prone mice, highlighting the close association between STING low-expression and JAK1-STAT1 signaling activation in B cells in autoimmune diseases. Our data provide a molecular insight into the novel role of STING in dsDNA-mediated inflammatory disorders.

CXCL13 as a new biomarker of systemic lupus erythematosus and lupus nephritis - from bench to bedside?

Different studies over the last decade have linked the B cell-attracting chemokine CXC ligand 13 (CXCL13) to the autoimmune disease systemic lupus erythematosus (SLE). A pathogenetic role of this chemokine for disease manifestation in SLE was described initially in mouse models for SLE. Mechanisms of CXCL13 actions were also identified in SLE patients. Moreover, various clinical studies have identified CXCL13 serum levels as a useful biomarker in patients with SLE of different ethnicities for disease activity. In addition, CXCL13 seems to be a promising marker for the diagnosis of lupus nephritis, one of the most severe complications of SLE. However, its exact place within the mechanisms that lead to SLE remains to be defined. Further research is needed to resolve more details of the pathomechanism and the signalling pathway of CXCL13 in SLE. Blocking CXCL13 or the signal pathways of CXCL13 is seen as a promising therapeutic approach for SLE and will be addressed in the near future. This review summarizes all papers that linked CXCL13 to SLE and highlights its importance in the pathogenesis and diagnosis of SLE.

Antibodies to early EBV, CMV, and HHV6 antigens in systemic lupus erythematosus patients

OBJECTIVES

We investigated the antibody levels against early antigens of Epstein-Barr virus (EBV), cytomegalovirus (CMV), and human herpesvirus 6 (HHV6) in systemic lupus erythematosus (SLE) patients and healthy controls, and further correlated these antibodies to haematology/biochemistry, serology, and disease activity measures.

METHOD

Immunoglobulin (Ig)M, IgG, and IgA levels against the DNA polymerase processivity factors of EBV, CMV, and HHV6, termed early antigen diffuse (EA/D), pp52, and p41, respectively, were determined in plasma samples from 77 SLE patients and 29 healthy controls by using enzyme-linked immunosorbent assays (ELISAs).

RESULTS

IgM, IgG, and IgA levels against EBV EA/D, and IgG and IgA levels against CMV pp52, were significantly higher in SLE patients compared with healthy controls. Furthermore, EBV EA/D- and CMV pp52-directed IgG levels were inversely and positively associated, respectively, with lymphocyte counts in SLE patients. None of the findings seemed to be associated with use of immunosuppressive medication.

CONCLUSIONS

Our results suggest strong, but opposite, associations of lytic EBV and CMV infections with SLE. The amplified humoral responses to EBV EA/D and CMV pp52 in our SLE patient cohort probably reflect aberrant control of EBV and CMV reactivation. However, reactivation of EBV appeared to correlate with lymphopenic manifestations in SLE patients whereas CMV reactivation seemed to correlate with increments in lymphocyte levels.

Viruses as potential pathogenic agents in systemic lupus erythematosus

Genetic and environmental factors appear to contribute to the pathogenesis of systemic lupus erythematosus (SLE). Viral infections have been reported to be associated with the disease. A number of exogenous viruses have been linked to the pathogenesis of SLE, of which Epstein-Barr virus (EBV) has the most evidence of an aetiological candidate. In addition, human endogenous retroviruses (HERV), HRES-1, ERV-3, HERV-E 4-1, HERV-K10 and HERV-K18 have also been implicated in SLE. HERVs are incorporated into human DNA, and thus can be inherited. HERVs may trigger an autoimmune reaction through molecular mimicry, since homology of amino acid sequences between HERV proteins and SLE autoantigens has been demonstrated. These viruses can also be influenced by oestrogen, DNA hypomethylation, and ultraviolet light (UVB) exposure which have been shown to enhance HERV activation or expression. Viral infection, or other environmental factors, could induce defective apoptosis, resulting in loss of immune tolerance. Further studies in SLE and other autoimmune diseases are needed to elucidate the contribution of both exogenous and endogenous viruses in the development of autoimmunity. If key peptide sequences could be identified as molecular mimics between viruses and autoantigens, then this might offer the possibility of the development of blocking peptides or antibodies as therapeutic agents in SLE and other autoimmune conditions.

Susceptibility to SLE in South Indian Tamils may be influenced by genetic selection pressure on TLR2 and TLR9 genes

INTRODUCTION

Systemic lupus erythematosus (SLE) is a multisystem autoimmune disorder with complex etiology. Genetics plays an important role in lupus pathogenesis through its influence on clinical and autoantibody phenotype of the disease. Toll like receptors (TLR) recognize molecular patterns of pathogens and activate the innate immune system. Their ability to identify nucleic acids makes them suitable candidates for investigation of their role in lupus pathogenesis. Hence, this study was carried out to analyze the G to A and C to T transitions in TLR2 and TLR9 genes respectively and to test their association with lupus susceptibility, clinical and autoantibody phenotypes in South Indian Tamils.

METHOD

Three hundred SLE patients fulfilling ACR 2012 criteria for SLE and 460 age, sex similar, ethnicity matched controls were recruited as cases and controls. TLR2 (R753Q) and TLR9 (-1237C/T) polymorphisms were analyzed by real time PCR.

RESULTS

The TLR2 gene remained monomorphic in patients and controls, the frequency of the homozygous wild type allele being 100% and 99.6% respectively. Hence, it did not confer susceptibility to SLE. The more frequent T allele of TLR9 gene conferred a significant risk to develop SLE (p=0.011, OR 1.69, 95% CI 1.1-2.6). Both the polymorphisms did not influence clinical or autoantibody phenotype of the disease.

CONCLUSION

Prevailing endemic infections in the Indian subcontinent may have exerted a selection pressure resulting in TLR2 gene remaining monomorphic and the TLR9 adapting to a mutation for its increased expression. These may have an additive effect in the presence of other genetic and environmental risk factors to confer susceptibility to SLE in South Indian Tamils.

The mosaic of environment involvement in autoimmunity: the abrogation of viral latency by stress, a non-infectious environmental agent, is an intrinsic prerequisite prelude before viruses can rank as infectious environmental agents that trigger autoimmune diseases

An autoimmune disease (AD), organ-specific or systemic, results from an aberrant response in which the protective immune system normally schooled to recognize and destroy invading infectious agents (viruses, etc.) instead fails to distinguish self-antigens and proceeds to attack and destroy the host's organs. There can be familial aggregation in which a single AD may occur in members of a family, or a single family may be afflicted with multiple ADs. Finally, sometimes multiple ADs co-occur in a single individual: the kaleidoscope of autoimmunity. Autoimmunity is a multifactorial process in which genetic, hormonal, immunological and environmental factors act in concert to materialize the mosaic of autoimmunity phenomenon. A genetically primed individual may yet not develop an AD: the contribution by an environmental factor (non-infectious or infectious) is essential for completion of the act. Of the non-infectious factors, stress plays a determinative step in autoimmunity in that it abrogates viral latency and thereby ordains the viruses to qualify as infectious environmental factors that trigger ADs. This is note-worthy as viruses rank first as the most important environmental triggers of ADs. Furthermore, all these viruses experience going through latency. Hence the hypothesis: "The abrogation of viral latency by stress, a non-infectious environmental agent, is an intrinsic prerequisite prelude before viruses can rank as infectious environmental agents that trigger autoimmune diseases". There is collaboration here between non-infectious- and infectious-agent to achieve the cause of autoimmunity. We say viral latency and stress have a covenant: continued perpetration of autoimmunity is dependent on the intervention by stress to reactivate latent infections.

Social Determinants of Health, the Chronic Care Model, and Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a chronic inflammatory rheumatic disease that disproportionately affects African Americans and other minorities in the USA. Public health attention to SLE has been predominantly epidemiological. To better understand the effects of this cumulative disadvantage and ultimately improve the delivery of care, specifically in the context of SLE, we propose that more research attention to the social determinants of SLE is warranted and more transdisciplinary approaches are necessary to appropriately address identified social determinants of SLE. Further, we suggest drawing from the chronic care model (CCM) for an understanding of how community-level factors may exacerbate disparities explored within social determinant frameworks or facilitate better delivery of care for SLE patients. Grounded in social determinants of health (SDH) frameworks and the CCM, this paper presents issues relative to accessibility to suggest that more transdisciplinary research focused on the role of place could improve care for SLE patients, particularly the most vulnerable patients. It is our hope that this paper will serve as a springboard for future studies to more effectively connect social determinants of health with the chronic care model and thus more comprehensively address adverse health trajectories in SLE and other chronic conditions.

Biomarkers in systemic lupus erythematosus: challenges and prospects for the future

The search for lupus biomarkers to diagnose, monitor, stratify, and predict individual response to therapy is currently more intense than ever before. This effort is essential for several reasons. First, epidemic overdiagnosis and underdiagnosis of lupus, even by certified rheumatologists, leads to errors in therapy with concomitant side effects which may be more serious than the disease itself. Second, identification of lupus flares remains as much an art as it is a science. Third, the capacity to stratify patients so as to predict those who will develop specific patterns of organ involvement is not currently possible but would potentially lead to preventive therapeutic strategies. Fourth, only one new drug for the treatment of lupus has been approved by the US Food and Drug Administration in over 50 years. A major obstacle in this pipeline is the dearth of biomarkers available to prove a patient has responded to an experimental therapeutic intervention. This review will summarize the challenges faced in the discovery and validation of lupus biomarkers, the most promising lupus biomarkers identified to date, and the promise of future directions.

Emerging and critical issues in the pathogenesis of lupus

Systemic lupus erythematosus (SLE) is a multisystemic, autoimmune disease, encompassing either mild or severe manifestations. SLE was originally labeled as being an immune complex-mediated disease, but further knowledge suggested its pathogenesis is motlier than that, involving complex interactions between predisposed individuals and their environment. People affected with SLE have their immune system skewed toward aberrant self-recognition usually after encountering a triggering agent. Defeats in early and late immune checkpoints contribute to tolerance breakdown and further generation and expansion of autoreactive cell-clones. B and T cells play a master role in SLE, however clues are emerging about other cell types and new light is being shed on SLE autoantibodies, since some of them display really harmful potential (pathogenic antibodies), while others are just connected with disease development (pathological antibodies) and may even be protective. Autoantibody generation is elicited by abnormal apoptosis and inefficient clearance of cellular debris causing intracellular autoantigens (e.g. nucleosomes) to persist in the extracellular environment, being further recognized by autoreactive cells. Here we explore the complexity of SLE pathogenesis through five core issues, i.e. genetic predisposition, B and T cell abnormalities, abnormal autoantigen availability, autoantibody generation and organ damage, relying on current knowledge and recent insights into SLE development.

Lupus and Epstein-Barr

PURPOSE OF REVIEW

Systemic lupus erythematosus (SLE) is a heterogeneous human disease influenced by a complex interplay of necessary, but not individually sufficient, factors. Although many genetic and environmental factors are associated with SLE, this review will focus on the evolving evidence for key Epstein-Barr virus (EBV)-specific roles in SLE, focusing on new experimental studies published during 2009, 2010, and 2011.

RECENT FINDINGS

SLE patients have a dysregulated immune response against EBV. EBV antigens exhibit structural molecular mimicry with common SLE antigens and functional molecular mimicry with critical immune-regulatory components. SLE patients, from a number of unique geographic regions, are shown to have higher rates of EBV seroconversion, especially against early EBV antigens, suggesting frequent viral reactivation. SLE patients also have increased EBV viral loads and impaired EBV-specific CD8 cytotoxic T cells, with impaired cytokine responses to EBV in lupus patients. Irregular cytokine production in plasmacytoid dendritic cells and CD69 CD4 T cells after stimulation with EBV has also been demonstrated.

SUMMARY

Recent advances demonstrate SLE-specific serologic responses, gene expression, viral load, T-cell responses, humoral fine specificity, and molecular mimicry with EBV, further supporting potential roles for EBV in lupus etiology and pathogenesis.

Contribution of toll-like receptor 9 gene single-nucleotide polymorphism to systemic lupus erythematosus

There are several studies on the association of TLR9 polymorphisms with systemic lupus erythematosus (SLE) in different ethnicities; however, the results are inconsistent. Therefore, we studied the distribution of the TLR9 C > T (rs352140) polymorphism in patients with SLE (n = 254) and controls (n = 521) in a Polish population. We did not observe significant differences in the prevalence of the TLR9 C > T genotype and alleles between patients with SLE and controls. However, we found a contribution of the T/T and T/C genotypes to renal [OR = 2.949 (95 % CI = 1.523–5.711, p = 0.001), (p_corr = 0.017)] and immunologic disorders [OR = 2.938 (95 % CI 1.500–5.755, p = 0.0012), (p_corr = 0.0204)] in SLE patients. Moreover, we observed a significant association between the TLR9 T/T and T/C genotypes and the presence of anti-dsDNA Ab [OR = 3.682 (1.647–8.230, p = 0.001), (p_corr = 0.017)]. Our studies suggest that the TLR9 C > T (rs352140) polymorphism might contribute to renal and immunologic disorders and to the presence of anti-dsDNA Ab.

Autoinflammatory diseases: how to put the fire inside the body out?

Autoinflammatory diseases (AIDs) are a group of distinct hereditable disorders characterized by unexplained, recurrent episodes of fever and severe inflammation, most commonly involving skin, joints, gut, and eyes. Mutations in inflammasome-related proteins, particularly in NOD-like receptor (NLR) genes, have been strongly associated with the occurrence of AIDs. However, new genes and dysfunctional proteins have recently been identified and the spectrum of AIDs is ever-expanding. In fact, it has been suggested to encompass other disorders which share some clinical features with AIDs, but are not clearly familial, or are not characterized by fever as a prominent symptom, or are polygenic. In this issue of Autoimmunity Reviews some novel and burning aspects of AIDs were covered and the relationship between AIDs and autoimmune diseases was discussed.

The Role of Hyaluronan and CD44 in the Pathogenesis of Lupus Nephritis

Systemic lupus erythematosus (SLE) is a prototype autoimmune disease that affects multiorgan systems. Lupus nephritis is one of the most severe manifestations of SLE whereby immune-mediated inflammation can lead to permanent damage within the glomerular, tubulo-interstitial, and vascular compartments of the kidney, resulting in acute or chronic renal failure. The mechanisms that regulate host inflammatory responses and tissue injury are incompletely understood. Accumulating evidence suggests that hyaluronan and its interaction with its cell surface receptor CD44 plays an important role in mediating pathogenic mechanisms in SLE. This paper discusses the putative mechanisms through which hyaluronan and CD44 contribute to the pathogenesis of SLE, with particular emphasis on lupus nephritis.

Epstein-Barr virus and systemic lupus erythematosus

The etiology of SLE is not fully established. SLE is a disease with periods of waning disease activity and intermittent flares. This fits well in theory to a latent virus infection, which occasionally switches to lytic cycle, and EBV infection has for long been suspected to be involved. This paper reviews EBV immunobiology and how this is related to SLE pathogenesis by illustrating uncontrolled reactivation of EBV as a disease mechanism for SLE. Studies on EBV in SLE patients show enlarged viral load, abnormal expression of viral lytic genes, impaired EBV-specific T-cell response, and increased levels of EBV-directed antibodies. These results suggest a role for reactivation of EBV infection in SLE. The increased level of EBV antibodies especially comprises an elevated titre of IgA antibodies, and the total number of EBV-reacting antibody isotypes is also enlarged. As EBV is known to be controlled by cell-mediated immunity, the reduced EBV-specific T-cell response in SLE patients may result in defective control of EBV causing frequent reactivation and expression of lytic cycle antigens. This gives rise to enhanced apoptosis and amplified cellular waste load resulting in activation of an immune response and development of EBV-directed antibodies and autoantibodies to cellular antigens.

Occupational risk factors for systemic lupus erythematosus: a nationwide study based on hospitalizations in Sweden

OBJECTIVE

To investigate possible associations between occupation and hospitalization for systemic lupus erythematosus (SLE) in a nationwide study.

METHODS

A nationwide database was constructed in Sweden by linking the Swedish Census to the Hospital Discharge Register to obtain data on all first hospitalizations with a primary or secondary diagnosis of SLE in adults during the study period (1970 to 2008). Standardized incidence ratios (SIR) and 95% CI were calculated for different occupations. Two cohorts were defined based on occupational titles recorded in Swedish census data in 1970 and 1980.

RESULTS

A total of 8921 male and 42290 female hospitalizations for SLE were retrieved in individuals aged over 15 years. High education (> 12 yrs) was associated with a lower risk of hospitalization for SLE among both women (SIR = 0.73) and men (SIR = 0.72). Among men with the same occupation in 2 consecutive censuses, increased risks (SIR) > 2.0 were present among artistic workers (2.52); shop managers and assistants (3.63); miners and quarry workers (6.04); shoe and leather workers (6.93); plumbers (2.21); other construction workers (2.08); glass, ceramic and tile workers (4.43); chimney sweeps (4.54); and military personnel (3.01). Among women with the same occupation in 2 consecutive censuses, no occupation was associated with SIR > 2.0.

CONCLUSION

Occupation may carry significantly increased risk of hospital admission for SLE. Especially among men, several occupations were associated with increased risks for SLE.

Induction of the ‘ASIA’ syndrome in NZB/NZWF1 mice after injection of complete Freund’s adjuvant (CFA)

Adjuvants, commonly used in vaccines, may be responsible for inducing autoimmunity and autoimmune diseases, both in humans and mice. The so-called ‘ASIA’ (Autoimmune/inflammatory Syndrome Induced by Adjuvants) syndrome has been recently described, which is caused by the exposure to a component reproducing the effect of adjuvants. The aim of our study was to evaluate the effect of injection of complete Freund’s adjuvant (CFA) in NZB/NZWF1 mice, a lupus-prone murine model. We injected 10 NZB/NZWF1 mice with CFA/PBS and 10 with PBS, three times, 3 weeks apart, and followed-up until natural death. CFA-injected mice developed both anti-double-stranded DNA and proteinuria earlier and at higher levels than the control group. Proteinuria-free survival rate and survival rate were significantly lower in CFA-treated mice than in the control mice ( p = 0.002 and p = 0.001, respectively). Histological analyses showed a more severe glomerulonephritis in CFA-injected mice compared with the control mice. In addition, lymphoid hyperplasia in spleen and lungs, myocarditis, and vasculitis were observed in the former, but not in the latter group. In conclusion, the injection of CFA in NZB/NZWF1 mice accelerated autoimmune manifestations resembling ‘ASIA’ syndrome in humans.

A prospective study of lupus and rheumatoid arthritis in relation to deployment in support of iraq and afghanistan: the millennium cohort study

The objective of this study was to prospectively assess the association between deployment in support of the operations in Iraq and Afghanistan and newly reported lupus and rheumatoid arthritis while also considering the effects of demographic, behavioral, and occupational characteristics. A total of 77,047 (2001-2003) and 31,110 (2004-2006) participants completed the baseline Millennium Cohort questionnaire and were resurveyed approximately every 3 years. Longitudinal analyses were used to assess the adjusted association between deployment to Iraq and Afghanistan with and without combat exposures and newly reported disease. After adjusting, deployment was not significantly associated with newly reported lupus compared with nondeployers. However, compared with nondeployers, deployers with and without combat exposures were significantly less likely to newly report rheumatoid arthritis. Women, non-Hispanic black, and Hispanic participants had a significantly elevated risk for both diseases. Overall, deployment was not associated with an increased risk of newly reported lupus or rheumatoid arthritis.

Association analysis of polymorphisms in lumican gene and systemic lupus erythematosus in a Taiwan Chinese Han population

OBJECTIVE

Lumican (LUM) is predominantly localized in areas of pathological fibrosis. To determine whether polymorphisms in LUM gene are associated with development of systemic lupus erythematosus (SLE), we analyzed 2 single-nucleotide polymorphisms (SNP) of LUM in a Taiwan Chinese Han population.

METHODS

Participants included 168 patients with SLE and 192 age-matched controls in whom examinations had excluded SLE. Genotyping of -628 A/-(rs17018757) and c.1567 T/C polymorphisms in LUM were carried out in each patient and control using the polymerase chain reaction-restriction fragment-length polymorphism method, and validated by Taqman SNP genotyping assay. Data were correlated with the development of SLE and various clinical symptoms by chi-square analysis.

RESULTS

Frequencies of C/C genotype and the C allele at c.1567 T/C were significantly higher in patients than controls. Polymorphism at c.1567 C/T was found to be associated with arthritis and photosensitivity in patients with SLE, which are both connective tissue-related symptoms.

CONCLUSION

The c.1567 T/C polymorphism of LUM is related to the development and clinical symptoms of SLE.

Type I interferon and systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a complex systemic autoimmune disease associated with multiple immunologic abnormalities. Prominent among these is upregulation of type I interferon (IFN)?a powerful immune adjuvant. IFN is, in part, produced in SLE in response to autoantigens in the form of self-nucleic acids and their associated nuclear proteins. Sources of these autoantigens include apoptotic and necrotic cells as well as neutrophils undergoing a specific form of cell death called NETosis. Although plasmacytoid dendritic cells are the main producers of IFN-a, other cells are important regulators of this process. Both genetic and environmental risk factors play a role in the development and pathogenesis of SLE. Further highlighting the importance of IFN, candidate gene and genome-wide association studies have identified a number of genes involved in type I IFN pathways associated with SLE. In this review, 3 monogenic deficiencies that result in lupus-like phenotypes and several polygenic variants that have been consistently associated with SLE are highlighted, and the relationship of these genes to IFN-a production is discussed. Clinical associations of the type I IFN pathway and the use of IFN-blocking agents as therapeutic agents in SLE are also reviewed.

Epigenetics in systemic lupus erythematosus: leading the way for specific therapeutic agents

Systemic lupus erythematosus (SLE) is a chronic autoimmune disorder of an unclearly determined etiology. Past studies, both epidemiological and biological, have implicated epigenetic influences in disease etiology and pathogenesis. Epigenetics describes changes in gene expression not linked to alterations in the underlying genomic sequence, and is most often typified by three modifications: methylation of DNA, addition of various side chains to histone groups and transcriptional regulation via short ncRNA sequences. The purpose of this article is to review the most important advances that link epigenetic changes to lupus. The contribution of DNA methylation changes to lupus pathogenesis is discussed. These include the role of apoptotic DNA, ultraviolet radiation, endogenous retroviruses, dietary contributions and aging. Hypomethylation of specific genes overexpressed in lupus T cells such as ITGAL (CD11a), CD40LG (CD40L), TNFSF7 (CD70), KIR2DL4 and PRF1 (perforin), and CD5 in lupus B cells seem to play an important role. Moreover, histone modifications such as increased global H4 acetylation in monocytes are highly associated with SLE. NcRNAs, especially miR-21, miR-148a and miR-126, control other elements of epigenetic regulation; particularly, transcription of the maintenance DNA methylation enzyme DNMT1. Epigenetic contributions to SLE etiology have been well established, but much is still unknown. Epigenome-wide studies coupled with functional analysis of the epigenomic changes discovered will uncover novel pathways important in disease pathogenesis. Epigenetic therapies for SLE may be feasible in the future, particularly if they are designed to target specific regions within the genome.