Single-cell RNA-seq reveals a persistent interferon signature in immune cells from systemic lupus erythematosus patients with high versus low polygenic risk scores despite antimalarial treatment.

PurposeLupus nephritis (LN) is a major clinical challenge and cause of significant morbidity and mortality in systemic lupus erythematosus (SLE). Today >180 SLE risk loci at Genome-wide significance (GWS, p...

Type I Interferon in Systemic Lupus Erythematosus and Other Autoimmune Diseases

Dysregulation of the antiviral immune response may contribute to autoimmune diseases. Here, we hypothesized that altered expression or function of MAVS, a key molecule downstream of the viral sensors RIG-I and MDA-5, may impair antiviral cell signalling and thereby influence the risk for systemic lupus erythematosus (SLE), the prototype autoimmune disease. We used molecular techniques to screen non-synonymous single nucleotide polymorphisms (SNPs) in the MAVS gene for functional significance in human cell lines and identified one critical loss-of-function variant (C79F, rs11905552). This SNP substantially reduced expression of type I interferon (IFN) and other proinflammatory mediators and was found almost exclusively in the African-American population. Importantly, in African-American SLE patients, the C79F allele was associated with low type I IFN production and absence of anti-RNA-binding protein autoantibodies. These serologic associations were not related to a distinct, functionally neutral, MAVS SNP Q198K. Hence, this is the first demonstration that an uncommon genetic variant in the MAVS gene has a functional impact upon the anti-viral IFN pathway in vivo in humans and is associated with a novel sub-phenotype in SLE. This study demonstrates the utility of functional data in selecting rare variants for genetic association studies, allowing for fewer comparisons requiring statistical correction and for alternate lines of evidence implicating the particular variant in disease.

Human γδ T cells recognize conserved endogenous and stress-induced antigens typically associated with autoimmune diseases. However, the role of γδ T cells in autoimmune diseases is not clear. Few autoimmune disease-related antigens recognized by T cell receptor (TCR) γδ have been defined. In this study, we compared Vδ2 TCR complementarity-determining region 3 (CDR3) between systemic lupus erythematosus (SLE) patients and healthy donors. Results show that CDR3 length distribution differed significantly and displayed oligoclonal characteristics in SLE patients when compared with healthy donors. We found no difference in the frequency of Jδ gene fragment usage between these two groups. According to the dominant CDR3δ sequences in SLE patients, synthesized SL2 peptides specifically bound to human renal proximal tubular epithelial cell line HK-2; SL2-Vm, a mutant V sequence of SL2, did not bind. We identified the putative protein ligand chaperonin-containing T-complex protein 1 subunit ζ (CCT6A) using SL2 as a probe in HK-2 cell protein extracts by affinity chromatography and liquid chromatography-electrospray ionization-tandem mass spectrometry analysis. We found CCT6A expression on the surface of HK-2 cells. Cytotoxicity of only Vδ2 γδ T cells to HK-2 cells was blocked by anti-CCT6A antibody. Finally, we note that CCT6A concentration was significantly increased in plasma of SLE and rheumatoid arthritis patients. These data suggest that CCT6A is a novel autoantigen recognized by Vδ2 γδ T cells, which deepens our understanding of mechanisms in autoimmune diseases.

We thank Huang and Zhang1 for their interest in our article entitled ‘Increased risk of systemic lupus erythematosus (SLE) in patients with autoimmune hemolytic anaemia (AIHA): a nationwide population-based cohort...

Cardiovascular (CV) mortality and morbidity are significant challenges in managing patients with systemic lupus erythematosus (SLE). Patients with SLE have a 2-fold higher risk of stroke and a 3-fold higher...

Correlation between soluble vascular endothelial growth factor receptor-1 (sVEGFR-1) concentration, VEGFR1 gene polymorphisms and systemic lupus erythematosus (SLE) risk remains unclear. The present case–control study comprised 254 SLE patients, 385 other rheumatic diseases patients and 390 healthy controls. Serum levels of sVEGFR-1 were detected by enzyme-linked immunosorbent assay. Seven VEGFR1 genetic variants (rs2296188, rs9943922, rs2296283, rs7324510, rs9554322, rs9582036, rs9554320) were genotyped by KASP. Serum levels of sVEGFR-1 were up-regulated in SLE and positively correlated with disease activity. Furthermore, serum sVEGFR-1 presented a distinctive elevation in SLE in comparison with other rheumatic diseases. Frequencies of allele T of rs2296283 and allele G of rs9554322 were significant lower in SLE patients (P = 0.003, P = 0.004). Frequencies of genotypes TT of rs2296188 and rs2296283 were declined in patients compared with healthy controls (P = 0.039, P = 0.033). CC genotype of rs7324510 and rs9582036 was negatively correlated with SLE risk (OR = 0.538, OR = 0.508). Distribution of GG, GC, GG + GC genotypes of rs9554322 were different between SLE patients and healthy controls (P = 0.027, P = 0.036, P = 0.010). Moreover, frequency of TC genotype of rs7324510 was higher in SLE patients with lupus headache (χ2 = 9.924, P = 0.039) and frequency of TC genotype of rs9943922 was lower in patients with cylindruriain (χ2 = 7.589, P = 0.026). Frequencies of allele C of rs7324510 and allele T of rs9943922 were decreased in SLE patients with cylindruria and hypocomplementemia, respectively (χ2 = 4.195, P = 0.041, χ2 = 3.971, P = 0.046). However, frequency of allele C of rs9554322 was increased in SLE patients with pyuria (χ2 = 11.702, P = 0.001). In addition, SLE patients carrying GG, GC, CC genotypes for rs9554322 had higher levels of serum sVEGFR-1. In conclusion, serum sVEGFR-1 was elevated in SLE patients and may be a disease marker. VEGFR1 gene polymorphisms related to risk of SLE in a Chinese Han population.

Atherosclerosis is an inflammatory disease and the major cause of cardiovascular disease (CVD) in general. Atherosclerotic plaques are characterized by the presence of activated immune competent cells, but antigens and underlying mechanisms causing this immune activation are not well defined. During recent years and with improved treatment of acute disease manifestations, it has become clear that the risk of CVD is very high in a prototypic autoimmune disease, systemic lupus erythematosus (SLE). SLE-related CVD and atherosclerosis are important clinical problems but may in addition also shed light on how immune reactions are related to premature atherosclerosis and atherothrombosis. A combination of traditional and nontraditional risk factors, including dyslipidaemia (and to a varying degree hypertension, diabetes and smoking), inflammation, antiphospholipid antibodies (aPL) and lipid oxidation are related to CVD in SLE. Premature atherosclerosis in some form leading to atherothrombosis is likely to be a major underlying mechanism, though distinctive features if any, of SLE-related atherosclerosis when compared with 'normal' atherosclerosis are not clear. One interesting possibility is that factors such as inflammation or aPL make atherosclerotic lesions in autoimmune disease more prone to rupture than in 'normal' atherosclerosis. Whether premature atherosclerosis is a general feature of SLE or only affects a subgroup of patients remains to be demonstrated. Treatment of SLE patients should also include a close monitoring of traditional risk factors for CVD. In addition, attention should also be paid to nontraditional risk factors such as inflammation and SLE-related factors such as aPL. Hopefully novel therapeutic principles will be developed that target the causes of the inflammation and immune reactions present in atherosclerotic lesions.

How does interferon‐α insult the vasculature? Let me count the ways

Latent autoimmunity across disease-specific boundaries in at-risk first-degree relatives of SLE and RA patients

Interplay between polygenic risk score and solar insolation: Implication for systemic lupus erythematosus diagnosis and pathogenesis

BackgroundLimited real-world data exists on clinical outcomes in systemic lupus erythematosus (SLE) patients by SLE Disease Activity Index 2000 (SLEDAI-2 K), hereafter, SLEDAI. We aimed to examine the association between SLEDAI score and clinical, patient-reported and economic outcomes in patients with SLE.MethodsRheumatologists from the United States of America and Europe provided real-world demographic, clinical, and healthcare resource utilization (HCRU) data for SLE patients. Patients provided self-reported outcome data, capturing their general health status using the EuroQol 5-dimension 3-level questionnaire (EQ-5D-3 L), health-related quality of life using the Functional Assessment of Chronic Illness Therapy (FACIT) and work productivity using the Work Productivity and Activity Impairment questionnaire (WPAI). Low disease activity was defined as SLEDAI score ≤ 4 and ≤ 7.5 mg/day glucocorticoids; patients not meeting these criteria were considered to have “higher” active disease. Data were compared between patients with low and higher disease activity. Logistic regression estimated a propensity score for SLE based on demographic and clinical characteristics. Propensity score matched analyses compared HCRU, patient-reported outcomes, income loss and treatment satisfaction in patients with low disease activity versus higher active disease.ResultsData from 296 physicians reporting on 730 patients (46 low disease activity, 684 higher active disease), and from 377 patients’ self-reported questionnaires (24 low disease activity, 353 higher active disease) were analyzed. Flaring in the previous 12 months was 2.6-fold more common among patients with higher versus low active disease. Equation 5D-3 L utility index was 0.79 and 0.88 and FACIT-Fatigue scores were 34.78 and 39.79 in low versus higher active disease patients, respectively, indicating better health and less fatigue, among patients with low versus higher active disease. Absenteeism, presenteeism, overall work impairment, and total activity impairment were 47.0-, 2.0-, 2.6- and 1.5-fold greater in patients with higher versus low disease activity. In the previous 12 months there were 28% more healthcare consultations and 3.4-fold more patients hospitalized in patients with higher versus low disease activity.ConclusionCompared to SLE patients with higher active disease, patients with low disease activity experienced better health status, lower HCRU, less fatigue, and lower work productivity impairment, with work absenteeism being substantially lower in these patients.

There are few existing studies that investigate the risk of systemic lupus erythematosus (SLE) associated with long-term exposure to air pollutants. This study aimed to explore associations between long-term exposure to air pollutants and incident SLE and further evaluate interactions and joint effects of genetic risk and air pollutants. A total of 459,815 participants were included from UK Biobank. The concentrations of air pollutants (fine particulate matter with diameter ≤2.5 μm [PM2.5], particulate matter diameter ≤10 μm [PM10], nitrogen dioxide [NO2], and nitrogen oxides [NOx]) were estimated by land-use regression model. We applied Cox proportional hazards model to explore linkages of air pollutants and incident SLE. The polygenic risk score (PRS) was used for further assessing the interactions and joint effects of genetic risk and air pollutants. A total of 399 patients with SLE were identified during a median follow-up of 11.77 years. There were positive associations between air pollutant exposure and incident SLE, as the adjusted hazard ratios were 1.18 (95% confidence interval [95% CI] 1.06-1.32), 1.23 (1.10-1.39), 1.27 (1.14-1.41), and 1.13 (1.03-1.23) for each interquartile range increase in PM2.5, PM10, NO2, and NOx, respectively. Moreover, participants with high genetic risk and high air pollution exposure had the highest risk of incident SLE compared with those with low genetic risk and low air pollution exposure (adjusted hazard ratio: PM2.5, 4.16 [95% CI 2.67-6.49]; PM10, 5.31 [95% CI 3.30,-8.55]; NO2, 5.61 [95% CI 3.45-9.13]; and NOx, 4.80 [95% CI 3.00-7.66]). There was a significant multiplicative interaction between NO2 and PRS. Long-term exposure to air pollutants (PM2.5, PM10, NO2, and NOx) may increase the risk of developing SLE.

Angiotensin II, one of the rennin-angiotensin system components, is important in the cardiovascular hemodynamic and plays an important role in the development of cardiovascular disease in systemic lupus erythematosus (SLE) patients. The angiotensin II, through interaction with angiotensin II type 1 receptor (AGTR1), promotes proliferation, inflammation and fibrosis. The single nucleotide polymorphism of the AGTR1 (dbSNP: rs5186) gene can be associated with development and progression of SLE disease. The aims of this study were to compare the frequency of AGTR1 rs5186 in SLE patients with healthy individuals and to evaluate possible association between AGTR1 A1166C gene polymorphism and serum level of lipids, neopterin and malondialdehyde in SLE patients from a population of West Iran. One hundred SLE patients and 98 healthy subjects were studied. The AGTR1 A1166C polymorphism was detected by polymerase chain reaction- restriction fragment length polymorphism method and the serum lipid profile was obtained by enzymatic method. Neopterin and malondialdehyde were detected using high-performance liquid chromatography. We did not detect significant association between AGTR1 A1166C polymorphism and the risk of SLE. The levels of triglyceride (225 ± 118 mg/dl), neopterin (30 ± 24 nmol/l) and malondialdehyde (25 ± 9.6 nmol/l) in SLE patients were significantly higher than those in control subjects (139 ± 56 mg/dl, p = 0.03, 6.4 ± 2, p = 0.03, 9.4 ± 2.5 nmol/l, p = 0.01, respectively). Individuals with AGTR1 AC + CC genotype had higher levels of total cholesterol and malondialdehyde compared with those with AGTR1 AA genotype. SLE patients with either AGTR1 AA or AGTR1AC + CC genotype had significantly higher malondialdehyde or neopterin levels compared with the corresponding control subjects. In conclusion, although the present study did not find any association between AGTR1 A1166C polymorphism and the risk of SLE, the presence of this polymorphism was associated with higher levels of malondialdehyde and higher concentration of neopterin in patients.

Background/Objectives: Systemic lupus erythematosus (SLE) is a complex autoimmune disease with a multifactorial origin involving genetic, epigenetic, and environmental determinants as well as some risk factors. Genetic predisposition has been quantified through polygenic risk scores (PRS), which integrate the cumulative effect of multiple single nucleotide variants (SNVs) associated with disease risk. Despite extensive research on immune and inflammatory pathways in SLE, the interplay between genetic susceptibility and metabolic dysfunction remains poorly understood. This study aimed to explore associations between SLE-related PRS and metabolic, inflammatory, and clinical parameters in adults participating in the METAINFLAMACIÓN-CM project (Hospital Universitario Puerta de Hierro Majadahonda, Madrid, Spain). Methods: Ninety-three participants were included: 56 SLE patients and 37 individuals with metabolic syndrome (MetS) as a reference group. PRS were computed based on validated lupus-associated SNVs. Results: SLE patients showed a distinct metabolic profile compared with the MetS group, characterized by lower BMI, visceral fat, blood pressure, glucose, and liver enzyme levels. Within the SLE cohort, PRS values varied markedly and correlated with specific clinical and biochemical features. Linear regression models revealed a significant inverse association between PRS in SLE and ferritin levels, whereas other metabolic and inflammatory markers (glucose, IL-6, LDL, CRP, neutrophils) were directly influenced by clinical factors. Conclusions: Polygenic predisposition contributes to variability in SLE metabolic phenotype but does not independently drive most inflammatory parameters. SLE patients displayed metabolic and inflammatory alterations relevant to cardiovascular risk, highlighting the importance of comprehensive cardiometabolic assessment. Integrating PRS with metabolic profiling may support precision personalized management and improve cardiovascular risk evaluation in SLE.