Environmental influences on systemic lupus erythematosus expression

Interplay between the Chaperone System and Gut Microbiota Dysbiosis in Systemic Lupus Erythematosus Pathogenesis: Is Molecular Mimicry the Missing Link between Those Two Factors?

Systemic lupus erythematosus (SLE) is a multifactorial autoimmune disease characterized by self-immune tolerance breakdown and the production of autoantibodies, causing the deposition of immune complexes and triggering inflammation and immune-mediated damage. SLE pathogenesis involves genetic predisposition and a combination of environmental factors. Clinical manifestations are variable, making an early diagnosis challenging. Heat shock proteins (Hsps), belonging to the chaperone system, interact with the immune system, acting as pro-inflammatory factors, autoantigens, as well as immune tolerance promoters. Increased levels of some Hsps and the production of autoantibodies against them are correlated with SLE onset and progression. The production of these autoantibodies has been attributed to molecular mimicry, occurring upon viral and bacterial infections, since they are evolutionary highly conserved. Gut microbiota dysbiosis has been associated with the occurrence and severity of SLE. Numerous findings suggest that proteins and metabolites of commensal bacteria can mimic autoantigens, inducing autoimmunity, because of molecular mimicry. Here, we propose that shared epitopes between human Hsps and those of gut commensal bacteria cause the production of anti-Hsp autoantibodies that cross-react with human molecules, contributing to SLE pathogenesis. Thus, the involvement of the chaperone system, gut microbiota dysbiosis, and molecular mimicry in SLE ought to be coordinately studied.

Potential Therapeutic Application and Mechanism of Action of Stem Cell-Derived Extracellular Vesicles (EVs) in Systemic Lupus Erythematosus (SLE)

Systemic lupus erythematosus (SLE) is a multisystemic autoimmune disease that affects nearly 3.41 million people globally, with 90% of the cases affecting women of childbearing age. SLE is a complex disease due to the interplay of various immunological pathways and mechanisms. This scoping review aims to highlight the latest research findings on the therapeutic mechanisms of action of EVs in SLE. Relevant research articles were identified using the PRISMA framework from databases such as PubMed/MEDLINE (National Library of Medicine), Scopus (Elsevier), and Web of Science: Core Collection (Clarivate Analytics) from July 2023 to October 2023. Eleven studies met the inclusion criteria and thus were included in this scoping review. The findings showed that EVs have therapeutic effects on ameliorating the disease progression of SLE. EVs can reduce the pro-inflammatory cytokines and increase the anti-inflammatory cytokines. Moreover, EVs can increase the levels of regulatory T cells, thus reducing inflammation. EVs also have the potential to regulate B cells to alleviate SLE and reduce its adverse effects. The scoping review has successfully analysed the therapeutic potential in ameliorating the disease progression of SLE. The review also includes prospects to improve the effects of EVs further to increase the therapeutic effects on SLE.

[Immunopathogenesis of systemic lupus erythematosus]

Insights into the immunopathogenesis of systemic lupus erythematosus (SLE) help to understand the complex disease patterns and to develop new treatment strategies. The disease manifestations essentially result from autoantibodies, immune complexes and cytokines. Particularly the propensity towards developing various autoantibodies is central to the disease itself; autoantibody specificities lead to highly variable organ manifestations. This review article delineates the clinically relevant state of knowledge on SLE pathogenesis, with the goal to establish a model useful for clinical practice, which also helps to classify the novel therapeutic approaches.

Spectrum of initial clinical presentations in Pakistani patients with systemic lupus erythematosus in the Arthritis Care Foundation lupus cohort

OBJECTIVE

The aim is to determine the pattern of initial clinical presentations of systemic lupus erythematous (SLE) in patients in a Pakistani lupus cohort.

METHODS

This is a multi-centric, retrospective, descriptive study that was done through the analysis of electronic records of patients registered with outdoor clinics of the Arthritis Care Foundation (ACF) from November 2021 to March 2023. Follow-up records of all patients diagnosed and labeled as SLE as per ACR/EULAR criteria 2019 were reviewed and only those patients whose initial presentation of SLE was documented at their incident visit (after verifying the signs and symptoms from record of their GP/referring physicians' visits) were included in the study. A total of 388 patients diagnosed with SLE were included in the study. Their data was then entered and analyzed by using SPSS 23. The qualitative data was expressed as percentages and numbers while the quantitative variables were expressed as mean and standard deviation. Data correlation was calculated by Chi-Square test, and a p-value of less than 0.05 was considered statistically significant.

RESULTS

Of our 388 patients, 360 (92.8%) were females and 28 (7.2%) were males giving a female-to-male ratio of 12:1. The mean age of our patients was 32.8 + 9.8 years. Mucocutaneous manifestations were most commonly reported in our patient group by 336 (86.7%) patients. Musculoskeletal complaints were the next most common presenting feature reported by 246 (61.9%) patients followed by constitutional symptoms in 78 (20.1%) patients, and renal involvement in 42 (10.8%) patients.

CONCLUSION

In our study, a majority of patients presented with mucocutaneous symptoms. It is therefore of paramount importance to suspect autoimmune diseases in patients with these system involvements.

HLA-DR genotypes in patients with systemic lupus erythematosus in Taiwan

BACKGROUND

Different human leukocyte antigen (HLA)-DR genotypes have been known to be associated with the risk of development of systemic lupus erythematosus (SLE) in different populations, although Lu et al. have reported previously that no correlation exists between the HLA-DR genotype and disease manifestation in SLE patients in Taiwan. We investigated the effects different HLA-DR genotypes had on SLE incidence in Taiwanese patients as to whether risk alleles were associated with different clinical manifestations, and the effects risk alleles had on the age of disease onset.

METHODS

Two hundred thirty-four SLE patients and 346 healthy controls were enrolled. HLA-DR genotyping was performed with the HLA FluoGene DRDQ kit for each subject. Chi-square tests and t tests were performed for statistical analysis.

RESULTS

HLA-DR2 was significantly more frequently found in SLE patients than in controls (odds ratio [OR] = 2.05, 95% CI, 1.44-2.92, p < 0.001). Notably, HLA-DR6 appeared to trend toward negative correlation with SLE, whereas HLA-DR8 appeared to trend toward positive correlation. HLA-DR2 patients had an earlier onset of disease as well as a higher prevalence of oral ulcer, avascular necrosis of bone, and renal involvement (lupus nephritis).

CONCLUSION

HLA-DR2 was associated with SLE susceptibility in this Taiwanese population as well as lower age of disease onset and more severe clinical manifestations.

Potential role of EBV and Toll-like receptor 9 ligand in patients with systemic lupus erythematosus

SLE is a multisystem autoimmune disease characterized by multiple immunological abnormalities including production of autoantibodies. While the etiology of SLE is largely unknown, it is generally accepted that both genetic and environmental factors contribute to disease risk and immune dysregulation. Production of IFN-α is important for protecting the host against infections; however, over stimulation of innate immune pathways can induce autoimmune disease. Environmental factors, particularly Epstein-Barr virus (EBV), have been proposed to play an important role in SLE disease. Improper engagement of Toll-like receptor (TLR) pathways by endogenous or exogenous ligands may lead to the initiation of autoimmune responses and tissue injury. EBV is shown to be a potent stimulant of IFN-α by TLR signaling cascades. Given the highlighted role of IFN-α in SLE pathogenesis and potential role of EBV infection in this disease, the present study is aimed at exploring the in vitro effects of EBV infection and CPG (either alone or in combination) on IFN-α. We also examined the expression level of CD20 and BDCA-4 and CD123 in PBMCs in 32 SLE patients and 32 healthy controls. Our results showed PBMCs treated with CPG-induced higher levels of IFN-α and TLR-9 gene expression fold change compared to cells treated with either EBV or EBV-CPG. Moreover, PBMCs treated with CPG produced significantly higher IFN-α concentration in supernatant compared to cells treated with EBV but not EBV-CPG. Our results further highlight the potential role of EBV infection and TLRs in SLE patients although more studies are warranted to ascertain the global imprint that EBV infection can have on immune signature in patients with SLE.

Activation of the cGAS-STING innate immune response in cells with deficient mitochondrial topoisomerase TOP1MT

The recognition that cytosolic mitochondrial DNA (mtDNA) activates cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) innate immune signaling has unlocked novel disease mechanisms. Here, an uncharacterized variant predicted to affect TOP1MT function, P193L, was discovered in a family with multiple early onset autoimmune diseases, including Systemic Lupus Erythematosus (SLE). Although there was no previous genetic association between TOP1MT and autoimmune disease, the role of TOP1MT as a regulator of mtDNA led us to investigate whether TOP1MT could mediate the release of mtDNA to the cytosol, where it could then activate the cGAS-STING innate immune pathway known to be activated in SLE and other autoimmune diseases. Through analysis of cells with reduced TOP1MT expression, we show that loss of TOP1MT results in release of mtDNA to the cytosol, which activates the cGAS-STING pathway. We also characterized the P193L variant for its ability to rescue several TOP1MT functions when expressed in TOP1MT knockout cells. We show that the P193L variant is not fully functional, as its re-expression at high levels was unable to rescue mitochondrial respiration deficits, and only showed partial rescue for other functions, including repletion of mtDNA replication following depletion, nucleoid size, steady state mtDNA transcripts levels and mitochondrial morphology. Additionally, expression of P193L at endogenous levels was unable to rescue mtDNA release-mediated cGAS-STING signaling. Overall, we report a link between TOP1MT and mtDNA release leading to cGAS-STING activation. Moreover, we show that the P193L variant has partial loss of function that may contribute to autoimmune disease susceptibility via cGAS-STING mediated activation of the innate immune system.

Environmental risk factors of systemic lupus erythematosus: a case-control study

Systemic lupus erythematosus (SLE) is a complicated chronic autoimmune disorder. Several genetic and environmental factors were suggested to be implicated in its pathogenesis. The main objective of this study was to examine how exposure to selected environmental factors was associated with SLE risk to support the development of disease preventive strategies. A case-control study was conducted at the Rheumatology outpatient clinic of Alexandria Main University Hospital, in Alexandria, Egypt. The study sample consisted of 29 female SLE patients, and 27 healthy female controls, who matched the cases on age and parity. Data were collected by a structured interviewing questionnaire. Blood levels of lead, cadmium, and zinc of all participants were assessed by flame atomic absorption spectrometry. The multivariate stepwise logistic regression model revealed that five factors showed significant association with SLE, namely living near agricultural areas, passive smoking, blood lead levels ≥ 0.075 mg/L, and exposure to sunlight (odds ratio (OR) 58.556, 95% confidence interval (CI) 1.897-1807.759, OR 24.116, 95% CI 1.763-329.799, OR 18.981, 95% CI 1.228-293.364, OR 9.549, 95% CI 1.299-70.224, respectively). Whereas walking or doing exercise were significantly protective factors (P = 0.006). The findings of this study add to the evidence that SLE can be environmentally induced. Preventive measures should be taken to address the environmental risk factors of SLE.

Autophagy dysregulation in trichloroethene-mediated inflammation and autoimmune response

Trichloroethene (TCE), an organic solvent extensively used for degreasing metals, can cause inflammatory autoimmune disorders [i.e., systemic lupus erythematosus (SLE) and autoimmune hepatitis] from both environmental and occupational exposure. Autophagy has emerged as a pivotal pathogenic factor in various autoimmune diseases. However, role of autophagy dysregulation in TCE-mediated autoimmunity is largely unknown. Here, we investigate whether autophagy dysregulation contributes to pathogenesis of TCE-mediated autoimmune responses. Using our established mouse model, we observed TCE-treated mice had elevated MDA-protein adducts, microtubule-associated protein light chain 3 conversion (LC3-II/LC3-I), beclin-1, phosphorylation of AMP-activated protein kinase (AMPK) and inhibition of mammalian target of rapamycin (mTOR) phosphorylation in the livers of MRL+ /+ mice. Suppression of oxidative stress with antioxidant N-acetylcysteine (NAC) effectively blocked TCE-mediated induction of autophagy markers. On the other hand, pharmacological autophagy induction with rapamycin significantly reduced TCE-mediated hepatic inflammation (NLRP3, ASC, Caspase1 and IL1-β mRNA levels), systemic cytokines (IL-12 and IL-17) and autoimmune responses (ANA and anti-dsDNA levels). Taken together, these results suggest that autophagy plays a protective role against TCE-mediated hepatic inflammation and autoimmunity in MRL+ /+ mice. These novel findings on the regulation of autophagy could help in designing therapeutic strategies for chemical exposure-mediated autoimmune responses.

HPV and molecular mimicry in systemic lupus erythematosus and an impact of compiling B-cell epitopes and MHC-class II binding profiles with in silico evidence

Epidemiological link between HPV and SLE is evolving. The possibility of HPV infection-induced molecular mimicry and systemic lupus erythematosus (SLE) was elucidated through detailed in silico analyses. Conserved regions in the structural protein sequences of high-risk HPV types were inferred, and sequence homologies between viral and human peptides were identified to delineate proteins implicated in SLE. B-cell epitopes and MHC-class II binding were compiled using Immune Epitope Database and ProPred II analysis tool. Molecular modeling and molecular dynamics/simulation (MDS) were performed using AutoDock Vina and GROMACS, respectively. Sequence alignment revealed 32 conserved regions, and 27/32 viral peptides showed varying similarities to human peptides, rich in B-cell epitopes with superior accessibility, high hydrophilicity, antigenicity and disposition to bind many class-II HLA alleles. Molecular docking of 13 viral peptides homologous (100%) to human peptides implicated in SLE showed that VIR-PEP1 (QLFNKPYWL) and VIR-PEP2 (DTYRFVTS) exhibited higher binding affinities than corresponding human peptides to SLE predisposing HLA-DRB1 allele. MDS of these peptides showed that the viral peptides had superior folding, compactness, and a higher number of hydrogen bonds than human peptides throughout the simulation period. SASA analysis revealed that the VIR-PEP1&2 fluctuated less frequently than corresponding human peptides. MM-PBSA revealed that the VIR-PEP2 complex exhibited higher binding energy than the human peptide complex. This suggests that highly conserved structural peptides of high-risk HPV types homologous to human peptides could compete and bind avidly to the HLA allele associated with SLE and predispose HPV-infected individuals to SLE through molecular mimicry.Communicated by Ramaswamy H. Sarma.

Dental caries and risk of newly-onset systemic lupus erythematosus: a nationwide population-based cohort study

OBJECTIVE

This study investigated whether patients with history of dental caries are associated with an increased risk of newly-onset systemic lupus erythematosus (SLE).

METHODS

A total of 501,461 carious patients and 258,918 controls without carious teeth were enrolled between 1997 and 2013 from the National Health Insurance Research Database. Subgroup analyses were conducted based on restorative materials including amalgam, composite resins, or both. The cumulative incidence and hazard ratios (HRs) of SLE development were derived after adjusting for age, sex, socioeconomic status, income, insured classification, comorbidities, and frequency of dental visit in a multivariable model.

RESULTS

The risk of SLE was significantly higher in carious patients (HR = 1.98, 95% confidence interval [CI] = 1.65-2.38) compared to controls. Dose-dependent relationship between caries and risk of SLE was identified. The risk of SLE was higher among those who had dental visits ≧11 (HR = 2.53, 95% CI = 1.86-3.43), followed by those with 3-10 dental visits (HR = 1.86, 95% CI = 1.36-2.54), when compared to those with 1-2 visits, and was higher among those who had carious teeth extractions ≧5 (HR = 1.88, 95% CI = 1.19-2.97), followed by those with 1-4 carious teeth extractions (HR = 1.36, 95% CI = 1.17-1.59) than those without extraction. The risk of SLE for dental caries management among different restorative materials, including amalgam, composite resins, or both, was not statistically different.

CONCLUSIONS

Patients with dental caries were associated with higher SLE risks. The relationship between dental caries and risk of SLE was dose-dependent, regardless of the material used for the restoration.

Prevalence of neuropsychiatric disorders in patients with systemic lupus erythematosus in Pakistan: A systematic review and meta-analysis

INTRODUCTION

By conducting a systematic review and meta-analysis, we investigated the prevalence of neuropsychiatric (NP) symptoms among systemic lupus erythematosus (SLE) patients in Pakistan.

METHODS

In this review work, three electronic databases (Web of Science, MEDLINE, and Google Scholar) and local databases were screened for 20 years from 1 January 2002 to 30 September 2022, to identify the articles evaluating the prevalence of NP symptoms in SLE patients in Pakistan. We performed a random-effects meta-analysis to estimate the prevalence of NPSLE. Statistical heterogeneity was measured by the I2 index, and subgroup meta-analyses were used to access the statistical heterogeneity. Furthermore, meta-regression models were used to examine the associations between prevalence estimates and study characteristics of interest. Three independent authors reviewed existing studies, extracted data, and rated the qualities of selected studies. This review was registered on PROSPERO (Registration no. CRD42022361798).

RESULTS

Thirteen studies met the inclusion criteria out of the 322 studies with a total of 2,003 SLE patients for this systematic review and meta-analysis. The prevalence of NP disorders in SLE patients was estimated to be 30.42% (95% CI:18.26-44.11%), with cognitive dysfunction being the most common (31.51%; 95% CI:1.28-76.27%), followed by headache (10.22%; 95% CI: 0.00-33.43%), seizures (5.96%; 95% CI: 3.80-8.53%), psychosis (3.64%; 95% CI: 2.38-5.13%), and neuropathy is the least common (0.86%; 95% CI: 0.00-2.74%). The heterogeneity between studies was significant (p < 0.01). The pooled prevalence of NP disorders among SLE patients was found highest in Punjab (41.21%) and lowest in Sindh (17.60%).

CONCLUSION

Findings from this study revealed that SLE patients have a high prevalence of NP disorders. The most common symptoms were cognitive dysfunctions, headaches, seizures, psychosis, and neuropathy. Clinicians can manage these potentially deadly and disabling diseases more effectively if they understand the incidence of each NP symptom in SLE patients. NP symptoms among SLE patients are at their peak in Pakistan; policymakers should devise preventive strategies to curb the disease.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/display_record. php?RecordID=361798, identifier CRD42022361798.

An Uncommon Correlation of Rheumatoid Arthritis and Lupus Nephritis: A Case Report on the Unusual Progression of Lupus Nephritis

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by chronic, widespread inflammation and multisystem organ damage. A serious complication of SLE is damage to the kidneys, which is called lupus nephritis (LN). LN typically manifests after five years post the diagnosis of SLE. However, in this case report, the authors present a 46-year-old female with no previous history of SLE, but rather a history of rheumatoid arthritis (RA) and mixed connective tissue disease (MCTD) with the rapid progression of shortness of breath and lower extremity edema in four months’ time. Upon further workup, large amounts of protein were found in the urine, consistent with nephrotic syndrome, and renal biopsy confirmed lupus nephritis. The patient ultimately achieved symptomatic relief with Benlysta® (belimumab), a recombinant human immunoglobulin G1λ (IgG1λ) monoclonal antibody. This report aims to highlight this unique presentation of both SLE and RA and bring awareness to and facilitate the early diagnosis and treatment of LN, thus mitigating permanent kidney damage.

Sex-Specific Associations Between Serum Lipids, Antinuclear Antibodies, and Statin Use in National Health and Nutrition Examination Surveys 1999-2004

Lipid metabolism contributes to the regulation of leukocyte activity and immune responses, and may serve as a therapeutic target in the pathophysiology and clinical management of autoimmune disorders. In addition to lipid-lowering properties, statins have been shown to exert anti-inflammatory and immunomodulatory effects within the context of autoimmunity. Importantly, autoimmune incidence and lipid markers differ between men and women, suggesting that the relationship between lipid metabolism and immune function may vary by sex. Therefore, we investigated whether a predictive, sex-specific relationship exists between serum lipids, statin use, and antinuclear antibodies (ANA)—a routine clinical marker of autoimmunity and immune dysfunction—in U.S. men and women (>20 years old; n = 1,526) from the National Health and Nutrition Examination Survey (NHANES) 1999–2004. Within this population, a greater proportion of women were positive for ANA (ANA+) and had higher ANA titers, as compared to men. While we did not observe statistical differences in average total cholesterol, LDL-cholesterol (LDL-C), HDL-cholesterol (HDL-C), or triglyceride levels in ANA positive (ANA+) vs. ANA negative (ANA–) men or women, we observed that a greater proportion of ANA+ women had high total cholesterol levels (>240 mg/dL) when compared to ANA+ men (13.0 vs. 9.0%), and that a greater percentage of ANA+ women had low HDL-C as compared to ANA+ men (29.2 vs. 19.6%). However, in logistic regression models, total cholesterol, LDL-C, and HDL-C levels were not able to predict ANA status, whereas elevated serum triglycerides (150 to < 200 mg/dL) were significantly less likely to be ANA+ vs. ANA– (OR 0.33; 95% CI 0.11–0.92) in men only. Interestingly, women who reported taking statins have significantly lower odds of being ANA+ (OR 0.25; 95% CI 0.09–0.76), whereas no significant association between statin use and ANA status was observed in men. Together, our findings provide novel insight into the relationship between lipid metabolism and autoimmunity by elucidating the limited, albeit sex-specific utility of routine clinical serum lipid levels to predict ANA status at the population level, while further identifying a sex-specific and protective role for statins in predicting ANA status in women.

Genotype Triad for HOTAIR rs10783618, LINC-ROR rs1942347, and MALAT1 rs3200401 as Molecular Markers in Systemic Lupus Erythematous

Accumulating evidence supports the implication of long non-coding RNAs (lncRNAs) in autoimmune diseases, including systemic lupus erythematosus (SLE). LncRNA variants could impact the development and/or outcome of the disease with variable diagnostic/prognostic utility in the clinic. We aimed to explore the contribution of HOTAIR (rs10783618), LINC-ROR (rs1942347), and MALAT1 (rs3200401) variants to SLE susceptibility and/or severity in 163 SLE patients and age-/sex-matched controls using real-time TaqMan allelic discrimination PCR. HOTAIR rs10783618*C/C was associated with a 77% increased risk of SLE (OR = 1.77, 95%CI = 1.09−2.87, p = 0.020) under the recessive model. Similarly, MALAT1 rs3200401*T/T carriers were three times more likely to develop SLE (OR = 2.89, 95%CI = 1.42−5.90) under the recessive model. While the rs3200401*T/C genotype was associated with a 49−57% decreased risk of SLE under codominant (OR = 0.51, 95%CI = 0.31−0.82, p < 0.001) and over-dominant (OR = 0.43, 95%CI = 0.27−0.68, p < 0.001) models. LINC-ROR rs1942347*A/A patients were more likely to have a positive family history of SLE. At the same time, HOTAIR rs10783618*C/C was associated with a higher frequency of arthritis (p = 0.001) and the presence of oral ulcers (p = 0.002), while patients carrying rs10783618*T/T genotype were more likely to develop hair loss (p < 0.001), weight loss (p = 0.001), and neurological symptoms (p = 0.003). In conclusion, the studied lncRNAs, HOTAIR, and MALAT1 gene polymorphisms confer susceptibility for SLE, providing a potential theoretical basis for their clinical translation in SLE disease.

Genome-wide association and Mendelian randomization study of blood copper levels and 213 deep phenotypes in humans

Metal elements are present in the human body, and their levels in the blood have important impacts on health. In this study, 2488 Chinese individuals were included in a genome-wide association study of 21 serum metal levels, with approximately 179,000 East Asian individuals in a bidirectional two-sample Mendelian randomization (MR) analysis, and 628,000 Europeans in a two-sample MR analysis. We identified two single nucleotide polymorphisms (SNPs) rs35691438 and rs671 that were significantly associated with serum copper levels (SCLs). The bidirectional two-sample MR analysis in the East Asian population showed that gamma-glutamyl transpeptidase levels have a causal effect on SCLs. SCLs have causal effects on six outcomes, namely risks of esophageal varix, glaucoma, sleep apnea syndrome, and systemic lupus erythematosus, white blood cell count, and usage of drugs affecting bone structure and mineralization. The two-sample MR analyses in the European population showed causal effects of erythrocyte copper levels on risks of carpal tunnel syndrome and compression fracture. Our results provide original insights into the causal relationship between blood metal levels and multiple human phenotypes.

A genome-wide association study in a Chinese population identifies SNPs associated with serum copper levels. Mendelian randomization analysis reveals causal effects on multiple human phenotypes in East Asian and European populations.

Real-world burden of systemic lupus erythematosus in the USA: a comparative cohort study from the Medical Expenditure Panel Survey (MEPS) 2016-2018

Objective

SLE is a chronic, multiorgan, autoimmune disease; however, current prevalence estimates are dated and often from non-generalisable patient populations, and quality of life and patient-reported outcomes in the real-world SLE population are not well-published. The present study used the Medical Expenditure Panel Survey (MEPS), a generalisable US data source encompassing a representative sample of regions/payers, to estimate SLE prevalence and characterise disease burden compared with non-SLE respondents.

Methods

Retrospective population-based survey data weighted to the full US population from MEPS for the calendar years 2016–2018, pooled over the full study period, was used. The primary inclusion criteria included adults with self-reported SLE and either a record of SLE-related medication and/or rheumatologist visit in the calendar year. A matched-control cohort was created and the general non-SLE MEPS population was matched to MEPS SLE respondents by gender, age, region and MEPS reporting year using a 1:5 ratio.

Results

From 2016 to 2018, 96 996 adults reported annual data in MEPS, of whom 154 respondents met the primary SLE definition, equivalent to 490 385 weighted number of adults with SLE. The prevalence of SLE was 195 (95% CI 149 to 242) per 100000, with greater prevalence observed in the US South, African-American/black and publicly insured people and females. SLE respondents reported limitations in physical function at 3 times greater rate (45% vs 15%; p<0.0001), higher rates of pain-limiting work (67% vs 39%; p<0.001) and feeling depressed ‘nearly every day’ (7% vs 2%; p<0.001) compared with non-SLE respondents. All-cause healthcare and prescription expenses were significantly higher in SLE respondents (US$17 270 vs US$8350 (p<0.0001) and US$4512 vs US$1952 (p<0.001), respectively, in 2018 US dollars).

Conclusion

Wide variation of SLE prevalence exists among patients of different regional, demographic and payer groups; SLE is associated with adverse quality of life, productivity and economic outcomes compared with non-SLE respondents.

Association of Viral Infection With the Development and Pathogenesis of Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease that causes multiple organ damage in women of childbearing age and has a relapsing-remitting course. SLE is caused by the interaction between genetic and environmental factors, however, its underlying triggers remain unknown. Among the environmental factors, the involvement of infections as a trigger for SLE, especially those of viral etiology, has been widely reported. Human endogenous retroviruses (HERVs) may put patients at a genetic predisposition to SLE, while the Epstein-Barr virus (EBV) may play a role as an environmental factor that triggers the development of SLE. It has been suggested that EBV-infected B-cells may become resistant to apoptosis, resulting in the activation, proliferation, and antibody production of autoreactive B-cells, which cause tissue damage in SLE. However, the interaction between the virus and immune cells, as well as the impact of the virus on the differentiation and dysfunction of immune cells, remain unclear. In this review, we focus on the relationship between the development and pathogenesis of SLE and viral infections, as well as the mechanism of SLE exacerbation via activation of immune cells, such as B-cells, based on the latest findings.

DNA Methylation of CD70 Promoter in Juvenile Systemic Lupus Erythematosus

INTRODUCTION

Epigenetic alterations in pathogenesis of systemic lupus erythematosus (SLE) have gained more attention recently in adults. We assessed the methylation of CD70 promoter, a costimulatory molecule on T cells, in juvenile SLE (JSLE), and compared this to that found in controls and the literature of adult SLE patients.

METHODS

DNA methylation status was evaluated on peripheral blood from JSLE patients and healthy controls.

RESULTS

Twenty-five patients with JSLE and 24 healthy controls were compared. JSLE patients had lower unmethylated CpG islands compared to the control group (mean ± SD; 0.78 ± 0.42 vs 10503.80 ± 39796.95). However, the difference was not significant (P-value; 0.22).

CONCLUSION

Despite hypomethylation of CD70 gene promoter in CD4+ T-cells from adult patients with SLE, no statistically significant differences observed in patients with JSLE compared with healthy controls. This may suggest a mechanism different in JSLE patients than in adults.

Altered Mitochondrial Homeostasis during Systemic Lupus Erythematosus Impairs Neutrophil Extracellular Trap Formation Rendering Neutrophils Ineffective at Combating Staphylococcus aureus

Inflammation involves a delicate balance between pathogen clearance and limiting host tissue damage, and perturbations in this equilibrium promote disease. Patients suffering from autoimmune diseases, such as systemic lupus erythematosus (SLE), have higher levels of serum S100A9 protein and increased risk for infection. S100A9 is highly abundant within neutrophils and modulates antimicrobial activity in response to bacterial pathogens. We reasoned that increased serum S100A9 in SLE patients reflects accumulation of S100A9 protein in neutrophils and may indicate altered neutrophil function. In this study, we demonstrate elevated S100A9 protein within neutrophils from SLE patients, and MRL/lpr mice associates with lower mitochondrial superoxide, decreased suicidal neutrophil extracellular trap formation, and increased susceptibility to Staphylococcus aureus infection. Furthermore, increasing mitochondrial superoxide production restored the antibacterial activity of MRL/lpr neutrophils in response to S. aureus These results demonstrate that accumulation of intracellular S100A9 associates with impaired mitochondrial homeostasis, thereby rendering SLE neutrophils inherently less bactericidal.

Epstein-Barr virus nuclear antigen 2 extensively rewires the human chromatin landscape at autoimmune risk loci

The interplay between environmental and genetic factors plays a key role in the development of many autoimmune diseases. In particular, the Epstein-Barr virus (EBV) is an established contributor to multiple sclerosis, lupus, and other disorders. Previously, we showed that the EBV nuclear antigen 2 (EBNA2) transactivating protein occupies up to half of the risk loci for a set of seven autoimmune disorders. To further examine the mechanistic roles played by EBNA2 at these loci on a genome-wide scale, we globally examined gene expression, chromatin accessibility, chromatin looping, and EBNA2 binding in a B cell line that was (1) uninfected, (2) infected with a strain of EBV lacking EBNA2, or (3) infected with a strain that expresses EBNA2. We identified more than 400 EBNA2-dependent differentially expressed human genes and more than 5000 EBNA2 binding events in the human genome. ATAC-seq analysis revealed more than 2000 regions in the human genome with EBNA2-dependent chromatin accessibility, and HiChIP data revealed more than 1700 regions where EBNA2 altered chromatin looping interactions. Autoimmune genetic risk loci were highly enriched at the sites of these EBNA2-dependent chromatin-altering events. We present examples of autoimmune risk genotype-dependent EBNA2 events, nominating genetic risk mechanisms for autoimmune risk loci such as ZMIZ1 Taken together, our results reveal important interactions between host genetic variation and EBNA2-driven disease mechanisms. Further, our study highlights a critical role for EBNA2 in rewiring human gene regulatory programs through rearrangement of the chromatin landscape and nominates these interactions as components of genetic mechanisms that influence the risk of multiple autoimmune diseases.

Association of microRNA-34a rs2666433 (A/G) Variant with Systemic Lupus Erythematosus in Female Patients: A Case-Control Study

Several microRNAs (miRNAs) are associated with autoimmune disease susceptibility and phenotype, including systemic lupus erythematosus (SLE). We aimed to explore for the first time the role of the miRNA-34a gene (MIR34A) rs2666433A > G variant in SLE risk and severity. A total of 163 adult patients with SLE and matched controls were recruited. Real-Time allelic discrimination PCR was applied for genotyping. Correlation with disease activity and clinic-laboratory data was done. The rs2666433 variant conferred protection against SLE development under heterozygous [A/G vs. G/G; OR = 0.57, 95%CI = 0.34-0.95], homozygous [A/A vs. G/G; OR = 0.52, 95%CI = 0.29-0.94], dominant [A/G + A/A vs. GG; OR = 0.55, 95%CI = 0.35-0.88], and log-additive [OR = 0.71, 95%CI = 0.53-0.95] models. Data stratification by sex revealed a significant association with SLE development in female participants under heterozygous/homozygous models (p-interaction = 0.004). There was no clear demarcation between SLE patients carrying different genotypes regarding the disease activity index or patients stratified according to lupus nephritis. Enrichment analysis confirmed the implication of MIR34A in the SLE pathway by targeting several genes related to SLE etiopathology. In conclusion, although the MIR34A rs2666433 variant conferred protection against developing SLE disease in the study population, it showed no association with disease activity. Replication studies in other populations are warranted.

Association of atopic dermatitis with an increased risk of systemic lupus erythematosus: A systematic review and meta-analysis

Context:

Previous studies on the association between atopic dermatitis (AD) and systemic lupus erythematosus (SLE) have yielded inconsistent results.

Aims:

To investigate the relationship between atopic dermatitis and systemic lupus erythematosus.

Settings and Design:

Systematic review and meta-analysis.

Materials and Methods:

A systematic review was conducted on EMBASE and MEDLINE databases from inception to March 2020 using a search strategy that consisted of terms related to AD and SLE. Eligible study must be either cohort or case-control study. For cohort studies, they must include patients with AD and comparators without AD, then follow them for incident SLE. For case-control studies, they must include cases with SLE and controls without SLE and examine their prior history of AD.

Statistical Analysis Used:

Meta-analysis of the studies was performed using a random-effect, generic inverse variance method to combine effect estimate and standard error. Funnel plot was used to assess publication bias.

Results:

A total of 21,486 articles were retrieved. After two rounds of review by three investigators, six case-control studies were qualified for the meta-analysis. The case-control study meta-analysis found a significantly increased odds of SLE among patients with AD with the pooled odds ratio of 1.46 (95% CI, 1.05–2.04).

Conclusions:

A significant association between AD and increased odds of SLE was observed by this systematic review and meta-analysis.

Impact of Climate Change on Eye Diseases and Associated Economical Costs

Climate change generates negative impacts on human health. However, little is known about specific impacts on eye diseases, especially in arid and semi-arid areas where increases in air temperatures are expected. Therefore, the main goals of this research are: (i) to highlight the association between common eye diseases and environmental factors; and (ii) to analyze, through the available literature, the health expenditure involved in combating these diseases and the savings from mitigating the environmental factors that aggravate them. Mixed methods were used to assess the cross-variables (environmental factors, eye diseases, health costs). Considering Southern Spain as an example, our results showed that areas with similar climatic conditions could increase eye diseases due to a sustained increase in temperatures and torrential rains, among other factors. We highlight that an increase in eye diseases in Southern Spain is conditioned by the effects of climate change by up to 36.5%; the economic burden of the main eye diseases, extrapolated to the rest of the country, would represent an annual burden of 0.7% of Spain’s Gross Domestic Product. In conclusion, the increase in eye diseases has a strong economic and social impact that could be reduced with proper management of the effects of climate change. We propose a new concept: disease sink, defined as any climate change mitigation action which reduces the incidence or morbidity of disease.

Intravenous Administration of Toll-Like Receptor Inhibitory Peptide 1 is Effective for the Treatment of Systemic Lupus Erythematosus in a Mus musculus Model

Objective

Systemic lupus erythematosus (SLE) is a common chronic autoimmune inflammatory disease According to recent studies, signaling through Toll-like receptor (TLR) protein, which promotes the production of inflammatory cytokines, leads to the development of SLE TLR-inhibitory peptide 1 (TIP1) has been newly identified for the treatment of autoimmune diseases.

Methods

The effect of TIP1 was analyzed in an SLE mouse model (MRL/lpr) The mice in the control treatment group (n=5) were administered an intravenous injection of phosphate-buffered saline twice weekly, whereas the mice in the TIP1 treatment group (n=6) were administered an intravenous injection of TIP1 (1 nmol/g) twice weekly MRL/mpj mice (n=5) were selected as normal controls The mice were injected for 4 weeks between 14 and 18 weeks of age, followed by assays of their spleen, kidneys, lymph nodes, serum, and urine.

Results

The antinuclear antibody and inflammatory cytokine (interferon-α) in the serum as well as levels of albumin in the urine of the mice in the TIP1 treatment group had decreased when compared to those of mice in the control treatment group Kidney inflammation in mice in the TIP1 treatment group was alleviated The mRNA expression levels of TLR7- or TLR9-related downstream signaling molecules also decreased in all organs of the mice in the TIP1 treatment group.

Conclusion

Intravenous treatment with TIP1 reduces symptoms and markers of inflammation in MRL/lpr mice Hence, TIP1 is a promising medication for the treatment of SLE.

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.

Risk of Systemic Lupus Erythematosus in Patients With Anti-phospholipid Syndrome: A Population-Based Study

Objective: To investigate the association between anti-phospholipid syndrome (APS) and the risk of newly diagnosed systemic lupus erythematosus (SLE). Methods: We used 2003-2013 data derived from Taiwan's National Health Insurance Research Database to conduct this nationwide, population-based. We identified AS patients newly diagnosed between 2005 to 2013 as the study group and applied age-sex matched (1:20) and propensity score-matched (PSM) (1:2) non-SLE individuals as controls. The association between APS and risk of incident SLE was determined by calculating hazard ratios (HRs) with 95% confidence intervals (CIs) using Cox proportional hazard regression analysis. Results: We identified 1,245 patients with APS as well as 24,900 age- and sex-matched non-APS controls and 727 APS patients as well as 1,454 PSM non-APS controls. We found that the risk for incident SLE in the APS group was 80.70 times higher than the non-APS group, and the association remained robust after PSM (HR, 28.55; 95% CI, 11.49-70.91). The increased risk for SLE in patients with APS mainly existed within 5 years after the diagnosis of APS. The sensitivity analyses found that the risk for SLE in patients with APS was consistent excluding patients with ITP/AIHA and using distinct definitions of SLE. Conclusion: The present population-based study revealed a robust association between SLE risk and recent APS and highlights the need for vigilance of SLE-associated symptoms in patients who had been diagnosed with APS.

Sex Hormones and Gender Influence the Expression of Markers of Regulatory T Cells in SLE Patients

Regulatory T cells have been implicated in the regulation and maintenance of immune homeostasis. Whether gender and sex hormones differentially influence the expression and function of regulatory T cell phenotype and their influence on FoxP3 expression remains obscure. We provide evidence in this study that the number and percent of human regulatory T cells (T_regs) expressing CD4⁺ and CD8⁺ are significantly reduced in healthy females compared to healthy males. In addition, both CD4⁺CD25^+hi and CD8⁺CD25^+hi subsets in healthy males have a 2-3 fold increase in FoxP3 mRNA expression compared to healthy females. Female SLE patients, compared to healthy women, have elevated plasma levels of estradiol and decreased levels of testosterone. Higher levels of testosterone correlate with higher expression of FoxP3 in CD4⁺CD25^hiCD127^low putative T_regs in women with SLE. Incubation of CD4⁺ regulatory T cells with 17β-estradiol at physiological levels generally decreased FoxP3 expression in females with SLE. These data suggest that females may be more susceptible than males to SLE and other autoimmune diseases in part because they have fewer T_regs and reduced FoxP3 expression within those cells due to normal E2 levels which suppress FoxP3 expression. In addition, low levels of plasma testosterone in women may further reduce the ability of the T_regs to express FoxP3. These data suggest that gender and sex hormones can influence susceptibility to SLE via effects on regulatory T cells and FoxP3 expression.

Circulating adiponectin levels and systemic lupus erythematosus: a two-sample Mendelian randomization study

OBJECTIVES

Several studies have reported increased serum/plasma adiponectin levels in SLE patients. This study was performed to estimate the causal effects of circulating adiponectin levels on SLE.

METHODS

We selected nine independent single-nucleotide polymorphisms that were associated with circulating adiponectin levels (P < 5 × 10-8) as instrumental variables from a published genome-wide association study (GWAS) meta-analysis. The corresponding effects between instrumental variables and outcome (SLE) were obtained from an SLE GWAS analysis, including 7219 cases with 15 991 controls of European ancestry. Two-sample Mendelian randomization (MR) analyses with inverse-variance weighted, MR-Egger regression, weighted median and weight mode methods were used to evaluate the causal effects.

RESULTS

The results of inverse-variance weighted methods showed no significantly causal associations of genetically predicted circulating adiponectin levels and the risk for SLE, with an odds ratio (OR) of 1.38 (95% CI 0.91, 1.35; P = 0.130). MR-Egger [OR 1.62 (95% CI 0.85, 1.54), P = 0.195], weighted median [OR 1.37 (95% CI 0.82, 1.35), P = 0.235) and weighted mode methods [OR 1.39 (95% CI 0.86, 1.38), P = 0.219] also supported no significant associations of circulating adiponectin levels and the risk for SLE. Furthermore, MR analyses in using SLE-associated single-nucleotide polymorphisms as an instrumental variable showed no associations of genetically predicted risk of SLE with circulating adiponectin levels.

CONCLUSION

Our study did not find evidence for a causal relationship between circulating adiponectin levels and the risk of SLE or of a causal effect of SLE on circulating adiponectin levels.

Quaternary Ammonium Compound Disinfectants Reduce Lupus-Associated Splenomegaly by Targeting Neutrophil Migration and T-Cell Fate

Hypersensitivity reactions and immune dysregulation have been reported with the use of quaternary ammonium compound disinfectants (QACs). We hypothesized that QAC exposure would exacerbate autoimmunity associated with systemic lupus erythematosus (lupus). Surprisingly, however, we found that compared to QAC-free mice, ambient exposure of lupus-prone mice to QACs led to smaller spleens with no change in circulating autoantibodies or the severity of glomerulonephritis. This suggests that QACs may have immunosuppressive effects on lupus. Using a microfluidic device, we showed that ambient exposure to QACs reduced directional migration of bone marrow-derived neutrophils toward an inflammatory chemoattractant ex vivo. Consistent with this, we found decreased infiltration of neutrophils into the spleen. While bone marrow-derived neutrophils appeared to exhibit a pro-inflammatory profile, upregulated expression of PD-L1 was observed on neutrophils that infiltrated the spleen, which in turn interacted with PD-1 on T cells and modulated their fate. Specifically, QAC exposure hindered activation of splenic T cells and increased apoptosis of effector T-cell populations. Collectively, these results suggest that ambient QAC exposure decreases lupus-associated splenomegaly likely through neutrophil-mediated toning of T-cell activation and/or apoptosis. However, our findings also indicate that even ambient exposure could alter immune cell phenotypes, functions, and their fate. Further investigations on how QACs affect immunity under steady-state conditions are warranted.

Health Disparities in Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a chronic multisystem autoimmune disease characterized by autoantibody production and diverse clinical manifestations. The many complex, overlapping, and closely associated factors that influence SLE susceptibility and outcomes include ethnic disparities, low adherence to medications, and poverty, and geography. Epigenetic mechanisms may provide the link between these environmental exposures and behaviors and the disproportionate burden of SLE seen in ethnic minorities. Attention to these modifiable social determinants of health would not only improve outcomes for vulnerable patients with SLE but likely reduce susceptibility to SLE as well through epigenetic changes.

Patients with asthma have a higher risk of systemic lupus erythematosus: a systematic review and meta-analysis

OBJECTIVE

This study aimed to investigate the association between asthma and risk of systemic lupus erythematosus (SLE) using systematic review and meta-analysis technique.

METHODS

Potentially eligible studies were identified from Medline and EMBASE databases from inception to March 2020 using search strategy that comprised of terms for "asthma" and "systemic lupus erythematosus." Qualified cohort study must consist of one cohort of patients with asthma and another cohort of individuals without asthma. Then, the study must report relative risk (RR) with 95% confidence intervals (95% CIs) of incident SLE between the two groups. Qualified case-control studies must consist of cases with SLE and controls without SLE. Then, the study must explore their history of asthma. Odds ratio (OR) with 95% CIs of the association between asthma status and SLE must be reported. Point estimates and standard errors were extracted from each study and were combined using the generic inverse variance method.

RESULTS

A total of 21,486 articles were identified. After two rounds of independent review by three investigators, three cohort studies and seven case-control studies met the eligibility criteria and were included into the meta-analysis. Patients with asthma had a significantly higher risk of SLE compared with individuals without asthma with the pooled odds ratio of 1.37 (95% CI 1.14-1.65; I² 67%). Funnel plot was symmetric and did not suggest the presence of publication bias.

CONCLUSIONS

The current study found a significant association between asthma and increased risk of SLE. Key Points • Studies have suggested an elevated risk of systemic lupus erythematosus among patients with asthma; however, the results from existing studies are inconsistent. • This meta-analysis included data from three cohort studies and seven case--control studies. • A significant association between asthma and elevated risk of systemic lupus erythematosus was observed, with the pooled odds ratio of 1.37 (95% CI 1.14-1.65; I² 67%).

Single-nucleotide polymorphisms influence the promoter activities of systemic lupus erythematosus-associated genes

Systemic lupus erythematosus (SLE) is a protypical autoimmune disease and genetic factors play important roles in its pathogenesis. Since present SLE susceptibility loci are mainly studied through meta-analysis of genome-wide association study, we performed promoter activity analysis to examine the biological functions of SLE-associated single-nucleotide polymorphisms (SNPs). We found at SNP positions rs1341239, rs1800795, rs1800796, rs1800872, rs1800871, rs187238, rs360719, rs8178822, rs3761549, different alleles influenced respective promoter activities in different manners, and the effects also appeared under glucocorticoid treatment. In addition, some SNPs showed strong correlations with levels of respective serum factors, but in most cases the associations were only demonstrated in SLE individuals. Our study has further disclose the functional roles of SLE-associate SNPs in SLE pathogenesis.

Lupus and Perioperative Complications in Elective Primary Total Hip or Knee Arthroplasty

Background

The number of patients with systemic lupus erythematosus (herein, lupus) undergoing total hip arthroplasty (THA) or total knee arthroplasty (TKA) is increasing. There is disagreement about the effect of lupus on perioperative complication rates. We hypothesized that lupus would be associated with higher complication rates in patients who undergo elective primary THA or TKA.

Methods

Records of more than 6.2 million patients from the National Inpatient Sample who underwent elective primary THA or TKA from 2000 to 2009 were reviewed. Patients with lupus (n = 38,644) were compared with those without lupus (n = 6,173,826). Major complications were death, pulmonary embolism, myocardial infarction, stroke, pneumonia, and acute renal failure. Minor complications were wound infection, seroma, deep vein thrombosis, hip dislocation, wound dehiscence, and hematoma. Patient age, sex, duration of hospital stay, and number of Elixhauser comorbidities were assessed for both groups. Multivariate logistic regression models using comorbidities, age, and sex as covariates were used to assess the association of lupus with major and minor perioperative complications. The alpha level was set to 0.001.

Results

Among patients who underwent THA, those with lupus were younger (mean age, 56 vs. 65 years), were more likely to be women (87% vs. 56%), had longer hospital stays (mean, 4.0 vs. 3.8 days), and had more comorbidities (mean, 2.5 vs. 1.4) than those without lupus (all p < 0.001). In patients with THA, lupus was independently associated with major complications (odds ratio [OR], 1.4; 95% confidence interval [CI], 1.1 to 1.7) and minor complications (OR, 1.2; 95% CI, 1.0 to 1.5). Similarly, among patients who underwent TKA, those with lupus were younger (mean, 62 vs. 67 years), were more likely to be women (93% vs. 64%), had longer hospital stays (mean, 3.8 vs. 3.7 days), and had more comorbidities (mean, 2.8 vs. 1.7) than those without lupus (all p < 0.001). However, in TKA patients, lupus was not associated with greater odds of major complications (OR, 1.2; 95% CI, 0.9 to 1.4) or minor complications (OR, 1.1; 95% CI, 0.9 to 1.3).

Conclusions

Lupus is an independent risk factor for major and minor perioperative complications in elective primary THA but not TKA.

Septicaemia is associated with increased disease activity and mortality in systemic lupus erythematosus: a retrospective analysis from Taiwan

OBJECTIVE

This study aimed to investigate how septicaemia, non-septicaemia infection and the disease itself are associated with disease activity and mortality in inpatients with systemic lupus erythematosus (SLE) in Taiwan.

METHODS

We retrospectively reviewed 1115 patients and enrolled 427 with SLE admitted for lupus flare-ups and co-morbidities. Disease activity and infection type/site were recorded and categorized according to the causes of admission and mortality into three categories, of which two were specified as follows: (a) septicaemia admissions, non-septicaemia admissions; and (b) septicaemia mortality, non-septicaemia infection mortality and non-infection mortality. The relationships between lupus flare-ups and mortality in different groups were analysed using an unpaired t-test, Mann-Whitney U-test and logistic regression.

RESULTS

Septicaemia was the major cause of mortality in SLE inpatients. There were 98 (22.95%) mortality patients among all 427 SLE patients. The septicaemia admissions had higher disease activity (SLE Disease Activity Index 2000 = 13.00 ± 7.98) than the non-septicaemia admissions (9.77 ± 5.72; p < 0.01). The mean current SLEDAI score of the septicaemia mortality group (14.91 ± 8.01) was higher than that of the non-septicaemia infection mortality group (10.05 ± 5.75; p = 0.02), in spite of the similar mean earlier SLEDAI score. The risk of mortality in the septicaemia mortality group due to previous septicaemia admissions was 13.2 times (odds ratio) higher than in the non-septicaemia infection mortality group and 15.6 times higher than in the non-infection mortality group.

CONCLUSION

Septicaemia relates to increased lupus disease activity and is associated with a greater risk of mortality in the SLE patients than other causes of admission. Fewer previous septicaemia admissions decrease the risk of septicaemia mortality.

Triggers of Autoimmunity: The Role of Bacterial Infections in the Extracellular Exposure of Lupus Nuclear Autoantigens

Infections are considered important environmental triggers of autoimmunity and can contribute to autoimmune disease onset and severity. Nucleic acids and the complexes that they form with proteins—including chromatin and ribonucleoproteins—are the main autoantigens in the autoimmune disease systemic lupus erythematosus (SLE). How these nuclear molecules become available to the immune system for recognition, presentation, and targeting is an area of research where complexities remain to be disentangled. In this review, we discuss how bacterial infections participate in the exposure of nuclear autoantigens to the immune system in SLE. Infections can instigate pro-inflammatory cell death programs including pyroptosis and NETosis, induce extracellular release of host nuclear autoantigens, and promote their recognition in an immunogenic context by activating the innate and adaptive immune systems. Moreover, bacterial infections can release bacterial DNA associated with other bacterial molecules, complexes that can elicit autoimmunity by acting as innate stimuli of pattern recognition receptors and activating autoreactive B cells through molecular mimicry. Recent studies have highlighted SLE disease activity-associated alterations of the gut commensals and the expansion of pathobionts that can contribute to chronic exposure to extracellular nuclear autoantigens. A novel field in the study of autoimmunity is the contribution of bacterial biofilms to the pathogenesis of autoimmunity. Biofilms are multicellular communities of bacteria that promote colonization during chronic infections. We review the very recent literature highlighting a role for bacterial biofilms, and their major components, amyloid/DNA complexes, in the generation of anti-nuclear autoantibodies and their ability to stimulate the autoreactive immune response. The best studied bacterial amyloid is curli, produced by enteric bacteria that commonly cause infections in SLE patients, including Escherichia coli and Salmonella spps. Evidence suggests that curli/DNA complexes can trigger autoimmunity by acting as danger signals, molecular mimickers, and microbial chaperones of nucleic acids.

Trace Elements Associated with Systemic Lupus Erythematosus and Insulin Resistance

Systemic lupus erythematosus (SLE) is a chronic inflammatory autoimmune disease of multifactorial origin. Studies have shown that trace elements such as zinc and copper may help maintain optimum function of the immune system and metabolism, while toxic metals such as lead may increase systemic autoimmunity. The current study aimed to assess the relationship between serum concentration of lithium (Li), vanadium (V), copper (Cu), zinc (Zn), molybdenum (Mo), cadmium (Cd), and lead (Pb) and SLE diagnosis, disease activity measured by SLE disease activity index (SLEDAI) and insulin resistance (IR). This case-control, cross-sectional study included 225 patients, 120 healthy controls, and 105 SLE patients. Serum concentration of Li, V, Cu, Zn, Mo, Cd, and Pb was measured. Serum concentrations of V (p < 0.001), Zn (p < 0.001), and Pb (p < 0.001) were lower and Mo (p < 0.001) and Li (p < 0.001) were higher in patients with SLE compared to healthy controls. SLE diagnosis was associated with higher serum Li (p < 0.001) concentration and lower V (p < 0.001), Zn (p = 0.003), and Pb (p = 0.020). Toxic metals and trace elements were not associated with disease activity. Levels of Cd were higher in patients with IR (p = 0.042). There was no significant association between IR and the other metals. The results indicate that SLE patients have different profiles of trace elements and toxic metals compared to healthy controls. While some toxic metals and trace elements were found to be associated with SLE diagnosis, they had no effect on disease activity and IR.

Vitamin D Receptor rs2228570 and rs731236 Polymorphisms are Susceptible Factors for Systemic Lupus Erythematosus

Background:

The Vitamin D receptor (VDR) polymorphisms are the candidate genetic variants for susceptibility to different disease including autoimmune disorders. In the present study, we aimed to assess the association between VDR polymorphisms and systemic lupus erythematosus (SLE) susceptibility in Southeast Iranian population.

Materials and Methods:

One hundred and twenty-seven patients with SLE and 139 controls were genotyped for VDR rs2228570, rs731236, and rs7975232 polymorphisms using polymerase chain reaction-restriction fragment length polymorphism method.

Results:

The VDR rs2228570 polymorphism was associated with higher risk of SLE in codominant, dominant, and overdominant models. Moreover, higher risk of SLE was observed in individuals with VDR rs731236 polymorphism in codominant, dominant, overdominant, and allelic models. The tAf haplotype of rs731236/rs7975232/rs2228570 polymorphisms was associated with higher risk of SLE.

Conclusion:

In conclusion, VDR rs2228570 and rs731236 polymorphisms and tAf haplotype were associated with SLE risk.

Lower Levels of Vitamin D Associated with Disease Activity in Colombian Patients with Systemic Lupus Erythematosus

BACKGROUND

Systemic Lupus Erythematosus (SLE) involves genetic, environmental, and hormonal alterations, including Vitamin D deficiency.

OBJECTIVE

To evaluate the association between vitamin D levels with anti-dsDNA, complement proteins, immunoglobulins levels and disease activity scores.

METHODS

A cross-sectional study was performed. The levels of 25-OH vitamin D were measured in patients older than 18 years with SLE according to ACR/97 [American College of Rheumatology 1997] from 2013 to 2015. The association was assessed by Mann-Whitney U and Kruskal Wallis tests for continuous variables, and by the Chi or Fisher exact test for the nominal variables.

RESULTS

Sixty-nine patients were included; 82% were women; the mean age was 38.5 years; 36.2% had low levels of vitamin D with higher consumption [p=0.006] of C4 and C3 complement proteins, plus higher levels of anti-dsDNA. Lower values of vitamin D were observed in patients with moderate to severe activity [p=0.0001] by SLEDAI [Systemic Lupus Erythematosus Activity Index] and general domain [p=0.039] and renal domain [p=0.009] by BILAG [British Isles Lupus Assessment Group] 2004. The mean vitamin D levels were higher in the group not receiving steroids when compared to those groups with dosages of 0.5-1mg/kg/d [p=0.048].

CONCLUSION

Lower levels of vitamin D are associated with greater complement protein consumption and higher disease activity rates. Therefore, it is important to evaluate vitamin D supplementation in patients with SLE as part of the treatment, especially when it includes the use of steroids.

The Impact of Vitamin D on Cognitive Dysfunction in Mice with Systemic Lupus Erythematosus

Background

A growing body of evidence suggests that systemic lupus erythematosus (SLE) may result in reversible cognitive dysfunction. Vitamin D is considered important for neurons. The therapeutic effect of vitamin D was evaluated in a rat model of SLE.

Material/Methods

There were 20 male MRL/lpr mice randomly divided into the SLE model group and the vitamin D group, in addition, 10 male C57BL 6J mice were used as the control (CON) group. Vitamin D was administered intraperitoneally (2 μg/kg) for 4 weeks. After 4 weeks of continuing intervention, we tested the cognitive function using the Morris water maze. The expression of vitamin D receptor (VDR), amyloid-β, caspase-3, and Bcl-2 were detected by western blot analysis.

Results

In the present study, we observed that vitamin D treatment alleviated neurobehavioral deficits in the mice with SLE. At the molecular levels, administration of vitamin D activated the expression of VDR and reduced the number of dead cells in the CA1 region of the hippocampus as well as regulated caspase-3 and Bcl-2 expression.

Conclusions

In conclusion, our results indicated that vitamin D played a protective role by suppressing inflammatory cytokines, thereby ultimately inhibiting the progression of apoptosis in a mouse model of SLE. Vitamin D may be promising as a protective intervention in SLE with cognitive dysfunction, and more and more experiments are warranted for its clinical testing in the near future.

Unraveling Race, Socioeconomic Factors, and Geographical Context in the Heterogeneity of Lupus Mortality in the United States

Objective

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease disproportionately affecting women and racial/ethnic minorities. We examined SLE-related mortality over time to assess whether the impact of race is attenuated when social economic status (SES) and geographic context are also considered.

Methods

This study examined whether social environment attenuates racial disparities in SLE-related mortality using race-geographical combinations of the US population known as the "Eight Americas." This framework jointly characterizes race, SES, and geographical location in relation to health disparities in the United States. Using National Vital Statistics and US Census data, we estimated mortality parameters for each of the Eight Americas.

Results

We identified 24 773 SLE deaths (2003-2014). Average annual mortality rates were highest among blacks in three race-geographical contexts: average-income blacks, southern low-income blacks, and high-risk urban blacks (14 to 15 deaths per million population) and lowest among nonblacks living in average-income settings (3 to 4 deaths per million population). Age at death was lowest (~47.5 years) for blacks and Asians and highest among low-income rural whites (~64.8 years).

Conclusion

Blacks sharing the same social and geographical contexts as whites were disproportionately more likely to die young. Although blacks inhabited three vastly different contexts, SLE-related mortality parameters did not vary among socially advantaged and disadvantaged blacks. These findings suggest that race may transcend SES and geographical parameters as a key determinant of SLE-related mortality.

Mechanistic Insights of Chemicals and Drugs as Risk Factors for Systemic Lupus Erythematosus

Systemic Lupus Erythematosus (SLE) is a chronic and relapsing heterogenous autoimmune disease that primarily affects women of reproductive age. Genetic and environmental risk factors are involved in the pathogenesis of SLE, and susceptibility genes have recently been identified. However, as gene therapy is far from clinical application, further investigation of environmental risk factors could reveal important therapeutic approaches. We systematically explored two groups of environmental risk factors: chemicals (including silica, solvents, pesticides, hydrocarbons, heavy metals, and particulate matter) and drugs (including procainamide, hydralazine, quinidine, Dpenicillamine, isoniazid, and methyldopa). Furthermore, the mechanisms underlying risk factors, such as genetic factors, epigenetic change, and disrupted immune tolerance, were explored. This review identifies novel risk factors and their underlying mechanisms. Practicable measures for the management of these risk factors will benefit SLE patients and provide potential therapeutic strategies.

Vitamin D status and its relationship with systemic lupus erythematosus as a determinant and outcome of disease activity

Background The importance of vitamin D (VD) in systemic lupus erythematosus (SLE) is being increasingly appreciated, with studies suggesting a relationship between VD deficiency and SLE onset/disease activity. We investigated VD status in SLE patients and its associations with disease activity in a geographical region of India receiving low solar ultraviolet-B (UV-B) index. Materials and methods We enrolled 109 SLE patients along with 109 healthy controls belonging to same ethnicity and localities. Demographic and clinico-laboratory information were recorded. VD status was assessed by estimating serum 25-hydroxyvitamin D (25-OH-D) concentrations (deficient: <20 ng/mL, insufficient: 21-29 ng/mL, and sufficient/normal: ≥30 ng/mL) using an enzyme-linked fluorescent assay (ELFA). The SLE Disease Activity Index (SLEDAI) scoring system was used to evaluate disease activity. The association between VD status and disease activity was assessed by univariate and multivariate approaches. Results Hypovitaminosis D was prevalent in 90.83% SLE patients [vs. 77.98% healthy controls; chi-squared (χ2) = 10.125, df = 2, p < 0.01]. SLEDAI scores and 25-OH-D values were inversely associated, which extended in a two-way manner as revealed by multiple logistic regression models. SLE patients with VD deficiency were more likely to have high/very high disease activity [adjusted odds ratio (OR) = 3.5, 95% confidence intervals (CI): 1.4-8.9]. Conversely, patients with high SLEDAI scores (>10) also had greater risks of being VD deficient (adjusted OR = 3.9, 95% CI: 1.5-10.8). Conclusion VD deficiency is widespread in SLE. The relationship appears to be bidirectional, with VD status associated both as determinant and outcome of disease activity in SLE.

HPV vaccines and lupus: current approaches towards preventing adverse immune cross-reactivity

INTRODUCTION

If not properly treated, human papillomavirus (HPV) infection may evolve from a common sexually transmitted disease to genital warts and cervical cancer. Various prophylactic HPV vaccines (HPVv), approved to reduce the incidence of the infection, have been found to be effective and safe; however, accounts of post-vaccination autoimmune phenomena, including systemic lupus erythematosus (SLE), have been reported in genetically susceptible individuals.

AREAS COVERED

Infectious agents play a role in breaking the immunologic tolerance to self-antigens, resulting in autoimmune events. There is molecular evidence supporting the involvement of HPV in SLE, with a high prevalence of L1 HPV peptide homology to proteins being associated with SLE. Therefore, approaches in vaccine preparations aiming to prevent adverse immune cross-reactivity are sought. Performing a broad search of the literature, we review the association between SLE, HPV, and HPVv, with a focus on the mechanisms of molecular mimicry and cross-reactivity, and the approaches currently being elaborated towards preventing such phenomena.

EXPERT COMMENTARY

The advantages of using low-similarity peptide antigens may be two-fold, abolishing the risk of cross-reactivity and eliminating the vaccine adjuvantation procedure. Vaccines based on pathogen unique sequences would provide effective vaccine preparation while curbing the risk for the human host.

Alcohol intake and risk of systemic lupus erythematosus: a Mendelian randomization study

OBJECTIVES

This study aimed to examine whether alcohol intake is causally associated with systemic lupus erythematosus (SLE).

METHODS

We performed a two-sample Mendelian randomization (MR) analysis using the inverse-variance weighted (IVW), weighted median, and MR-Egger regression methods. We used the publicly available summary statistics of alcohol intake frequency from the UK Biobank genome-wide association studies (GWASs; n = 336,965) as the exposure and an SLE GWAS consisting of 1311 SLE and 1783 control subjects of European descent as the outcome.

RESULTS

We selected 20 single nucleotide polymorphisms (SNPs) associated with alcohol intake frequency at genome-wide significance as instrumental variables to improve inference. The IVW method found no evidence to support a causal association between alcohol intake and SLE (beta = -0.413, SE = 0.513, p = 0.421). The MR-Egger regression revealed that directional pleiotropy was unlikely to bias the result (intercept = 0.031, p = 0.582). The MR-Egger analysis found no causal association between alcohol intake and SLE (beta = -1.494, SE = 1.996, p = 0.464). Likewise, the weighted median approach also did not provide evidence of a causal association between alcohol intake and SLE (beta = -0.538, SE = 0.574, p = 0.349). The MR estimates determined using the IVW, weighted median, and MR-Egger regression methods were consistent and results from a "leave-one-out" analysis demonstrated that no single SNP was driving the IVW point estimate.

CONCLUSIONS

The results of MR analysis do not support a causal inverse association between alcohol intake and SLE occurrence.

Significance and impact of dietary factors on systemic lupus erythematosus pathogenesis

Systemic lupus erythematosus (SLE) is an autoimmune disease of unknown etiology, although its mechanisms involve genetic, epigenetic and environmental risk factors. Considering that SLE pathogenesis is yet to be explored, recent studies aimed to investigate the impact of diet, in terms of triggering or altering the course of the disease. To study the impact of diet on SLE pathogenesis, we conducted a search on Pubmed using the keywords 'diet and autoimmune diseases', 'diet and lupus', 'caloric restriction and lupus', 'polyunsaturated fatty acids and lupus', 'vitamin D and lupus', 'vitamin C and lupus' 'vitamin E and lupus' 'vitamin A and lupus' 'vitamin B and lupus', 'polyphenols and lupus', 'isoflavones and lupus', 'minerals and lupus', 'aminoacids and lupus', 'curcumin and lupus' and found 10,215 papers, from which we selected 47 relevant articles. The paper clearly emphasizes the beneficial role of personalized diet in patients with SLE, and the information presented could be used in daily practice. Proper diet in SLE can help preserve the body's homeostasis, increase the period of remission, prevent adverse effects of medication and improve the patient's physical and mental well-being.

The role of dietary sodium in autoimmune diseases: The salty truth

Autoimmune diseases are a group of heterogeneous condition that occur secondary to the intrinsic loss of tolerance to self- antigens. In genetically susceptible individuals, the complex interplay of environmental factors and epigenetic deregulations have been proposed to drive disease etiopathogenesis. Various environmental variables have been identified including viral infections, exposure to pollutants, stress and dietary factors. Sodium, a major constituent of salt is essential for mammalian physiology. However, high salt intake may play a role in the development of autoimmune diseases. Several lines of evidence point toward the role of high sodium intake in reversing the suppressive effects of Regulatory T cells (Tregs) and instead promoting cellular shift toward T-helper (Th)-1 and Th17 pro-inflammatory phenotypes. These effects have been attributed to cascade of events that ultimately results in downstream activation of serum glucocorticoid kinase 1 (Sgk1). In vivo, various autoimmune animal models have confirmed the role of high sodium diet in the emergence and the exacerbation of autoimmune conditions including for instance Experimental Autoimmune Encephalomyelitis model for multiple sclerosis, MRL/lpr mouse model for lupus nephritis, collagen induced arthritis model for rheumatoid arthritis, and dextran sulfate sodium induced colitis, and TNBS-induced colitis models for Crohn's disease. Clinical epidemiological studies are scarce. High sodium intake was associated with increased risk of rheumatoid arthritis disease emergence. In multiple sclerosis, some studies suggest a relation to clinical exacerbation rates however other studies did not corroborate these results. Taken together, high dietary salt intake plays a role in the spectrum of autoimmune disease etiology. Further research is warranted to better characterize such relationship and assist in identifying individuals that would benefit from dietary salt restriction.

Adipokine interactions promote the pathogenesis of systemic lupus erythematosus

BACKGROUND

Adipokines are chemical mediators released from adipose tissue involved in regulation of appetite, insulin sensitivity, immune system and inflammatory responses. Adipokines contributes to low grade inflammatory response in autoimmune disease like Systemic Lupus Erythematosus (SLE) but the pathophysiology is yet not clear. The aim of this study is to understand role of adipokine interactions in SLE disease pathogenesis.

METHODS

Sixty newly diagnosed treatment naïve SLE patients fulfilling the ACR criteria and forty age-sex matched healthy subjects were enrolled in thiscase-control study. Disease activity in SLE patients was evaluated using SELENA-SLEDAI. Array of adipokines, C1q circulating immune complexes (C1q-CIC), anti-C1q, anti-ribososmal P0 (anti-RibP0) and anti-mitochondrial antibodies (AMA) levels were detected by ELISA. Antinuclear antibodies (ANA) and anti-dsDNA autoantibodieswere detected by Indirect Immunofluorescence (IIF), while antigen specificities were detected by Immunoassay blot. Serum levels of C3 and C4 complement factors were assessed by nephlometer.

RESULTS

Statistically significant elevation in progranulin, adipsin and resistin levels was seen among SLE patients when compared to healthy controls (p < 0.0001). Leptin and omentin levels were significantly reduced in SLE patients (p < 0.0001). There was no statistically significant difference in serum adiponectin, chemerin and visfatin levels when these two groups were compared (p > 0.05). Adiponectin, adipsin and resistin levels were elevated in SLE patients with renal manifestations (p < 0.05). Reduced leptin levels were significantly associated with presence of renal manifestations (p < 0.05). Adiponectin levels positively correlated with disease activity (r = 0.294, p = 0.027) whereas negatively correlated with C3 levels (r = -0.439, p = 0.0007). A positive correlation was observed between hypocomplementemia and leptin levels (p < 0.05). Leptin levels were negatively correlated with disease activity, anti-dsDNA, C1q-CIC and anti-C1q levels (p < 0.05). A significant positive correlation was observed between progranulin levels and anti-ribosomal P0 antibodies (r = 0.499, p < 0.0001).

CONCLUSION

Adipokines levels and associated clinical manifestations suggest involvement of adipokines in disease pathogenesis of SLE. SLE disease activity and complement components may suggest regulatory effect of adipokines (adiponectin and leptin) on disease pathogenesis. Further studies on adipokines in SLE patients with renal manifestations may propose them as prognostic markers in renal damage.

TRIAL REGISTRATION

NA.