New insights into the immunopathogenesis of systemic lupus erythematosus

Mitochondria dysfunction: A trigger for cardiovascular diseases in systemic lupus erythematosus

Cardiovascular disease (CVD), including pericarditis, myocarditis, sudden cardiac death, coronary heart disease, and stroke, are leading contributors to morbidity and mortality in systemic lupus erythematosus (SLE) patients. Emerging evidence highlights mitochondrial dysfunction as a key driver of cardiovascular pathology in SLE, with impaired oxidative phosphorylation, altered membrane potential, and disrupted metabolic processes promoting oxidative stress, inflammatory activation, and endothelial dysfunction. This review critically examines mitochondrial contributions to CVD in SLE, comparing these mechanisms with those in non-SLE CVD to highlight SLE-specific mitochondrial vulnerabilities. Furthermore, we discuss preclinical and clinical findings supporting mitochondrial pathways as potential therapeutic targets, aiming to bridge gaps in current understanding and outline future research directions. By synthesizing current knowledge of mitochondrial dysregulation, this review proposes therapeutic strategies to improve cardiovascular outcomes and advance patient care in SLE.

Improved diagnosis of systemic lupus erythematosus with human-derived double-stranded DNA antigen

Anti-double-stranded DNA antibodies (anti-dsDNA) serve as a crucial serological indicator for systemic lupus erythematosus (SLE). Chemiluminescent immunoassay (CIA) is mainly used in clinical diagnosis of SLE, but suffers from low specificity, partially because the use of dsDNA antigens of varied sources in current CIA kits that sometimes led to controversial results. On the basis that anti-dsDNA in healthy individuals tend to selectively bind with dsDNA originating from pathogens, whereas pathogenic anti-dsDNA in SLE patients bind all forms of dsDNA, here we proposed the use of dsDNA fragment derived from human genome as antigen (synthesized via PCR using the human genomic DNA as the template). A magnetic bead-based immunofluorescence assay (IFA) was thus developed for SLE diagnosis, which exhibited improved sensitivity and specificity over CIA using the WHO reference reagent (15/174) as standard. For clinical serum sample analysis (n = 590), IFA exhibited an accuracy of 71.9% that was higher than CIA (65.3%). Crucially, the IFA results exhibited stronger correlations with the activity of SLE, renal involvement, and its prognosis. Besides the improved clinical diagnosis, the proposed IFA also holds great promise in assay standardization due to the high homogeneity of the synthetic dsDNA.

Association between peripheral activated naive and double negative 2 B-cell subsets and clinical parameters in lupus nephritis patients

Altered composition of B-cell compartments is a known feature in patients with systemic lupus erythematosus (SLE). However, deep characterisation of B-cell subsets and their relation to clinical manifestations and disease activity in patients is limited. In this study, we analysed peripheral B-cell subsets phenotype in SLE (n = 35) and healthy controls (HCs, n = 15) by spectral flow cytometry. Disease activity was stratified as inactive (SLEDAI-2 K score 0, n = 2), mild (SLEDAI-2 K score 1-5, n = 12), moderate (SLEDAI-2 K score 6-10, n = 6) or high (SLEDAI-2 K > 10, n = 15). An elevated proportion of activated naive (aNAV), double negative 2 (DN2) and plasmablasts (PB) was observed in patients with high disease activity, compared to other groups of patients and HCs. An upregulation of BTLA was found on both aNAV and DN2 and shifted to lower levels with increasing disease activity. In lupus nephritis (LN) patients (n = 21), aNAV B-cells were especially expanded and positively correlated with DN2 (r = 0.5, p = 0.019) and PB (r = 0.43, p = 0.048). Also, correlation was observed between DN2 and PB (r = 0.6, p = 0.003). Moreover, aNAV frequencies positively correlated with SLEDAI-2 K score, and negatively with the complement fractions C3 and C4. Further, aNAV, DN2 and PB were more expanded in association with positive anti-dsDNA antibodies, rather than other antibody specificities (anti-Sm). These data suggest roles of extrafollicular B cells as key players in disease development of LN. Their association with presence of anti-dsDNA antibodies may indicate their value as candidate biomarkers of kidney involvement in SLE.

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

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

Neutrophil extracellular traps as a potential marker of systemic lupus erythematosus activity

BACKGROUND

The heterogeneity of systemic lupus erythematosus (SLE) poses a significant challenge in identifying biomarkers for assessing disease activity. Currently, there is a paucity of established biomarkers capable of evaluating SLE flares. This study aimed to identify novel biomarkers that exhibit improved diagnostic accuracy in assessing SLE activity.

METHODS

A cross-sectional study was conducted at Zhongshan Hospital Xiamen University from August 2021 to April 2024,enrolling 118 patients with SLE, including 81 cases of active SLE, 50 cases of active lupus nephritis (LN) and 30 cases of active non-LN. The objective was to evaluate the diagnostic accuracy of novel biomarker called Neutrophil Extracellular Traps(NETs) for SLE activity and analyze its correlations with conventional biomarkers such as complement C3, C4, and anti-dsDNA.

RESULTS

Serum NETs levels were significantly elevated in patients with active SLE and active LN(P < 0.001). Furthermore, positive correlations were observed between NETs levels and disease activity score based on Systemic Lupus Erythematosus Disease Activity Index-2 K (SLEDAI-2 K) (r = 0.64, P < 0.001), as well as anti-dsDNA antibody (r = 0.54, P < 0.001).Conversely, the NETs levels were negativity correlated with complement C3 concentration (r = -0.50, P < 0.001), as well as C4 concentration (r = -0.34,P < 0.001). Univariate and multivariate analysis revealed two biomarkers performed statistical significance: NETs (OR = 6.802, 95 %CI: 2.414-19.167,P < 0.001) and anti-dsDN A(OR = 3.95,95 %CI:1.582-9.864, P = 0.003). NETs had the highest AUC of 0.82(P < 0.001), with a cut-off at 515.47 ng/L demonstrating 61.63 % sensitivity and 96.87 % specificity. For the active LN group, the AUC was found to be 0.97 (P < 0.001), with a cutoff value of 515.47 ng/L, sensitivity of 100 %, and specificity of 59.76 %. Moreover, the active non-LN group had AUC of 0.70 (P = 0.007), with the same cutoff value, sensitivity of 89.61 %, and specificity of 51.61 %.

CONCLUSION

In contrast to conventional laboratory markers, serum NETs represent a novel diagnostic marker for assessing disease activity in SLE, demonstrating promising potential for clinical application.

Type I interferon-stimulated genes predict clinical response to belimumab in systemic lupus erythematosus

The type I interferon (IFN-I) response is crucial in systemic lupus erythematosus (SLE). The mRNA level of interferon-stimulated genes (ISGs) is widely used for evaluating the activity of IFN in SLE. However, the character of ISGs in belimumab-treated SLE patients has not be reported. In this study, we enrolled 53 SLE patients undergoing belimumab treatment and assessed their clinical responses at 3, 6, and 12 months. The expression levels of 25 ISGs in Peripheral blood mononuclear cells (PBMCs) were quantified at baseline and at 3 months using quantitative real-time PCR. Using Least absolute shrinkage and selection operator (LASSO)-logistic regression, five genes (CXCL10, EPSTI1, HECR6, IFI27, IFIH1) were identified to predict belimumab efficacy. The IFN signature score, a multivariate logistic regression model based on the change rates of these genes, positively predicted the SLE responder index (SRI) at 12 months, with an area under curve of 0.940 in receiver operating characteristic and favorable outcomes in decision curve analysis. Patients with an IFN signature score ≥0 had higher SRI response rates, better clinical markers (including SLE disease activity index 2000 scores, anti-dsDNA, IgG levels, daily doses of prednisone, and higher complement C3 and C4 levels), and faster B cell decline than those with scores <0. In conclusion, after 3 months of belimumab treatment, the expression levels of IFN-I-inducible genes varied, and the IFN signature score reliably forecasted the SRI response at 6 and 12 months.

FASN contributes to the pathogenesis of lupus by promoting TLR-mediated activation of macrophages and dendritic cells

Hyper-activations of monocytes/macrophages and dendritic cells (DCs) contribute to the pathogenesis of various autoimmune diseases, such as systemic lupus erythematosus (SLE). Fatty acid synthase (FASN) is essential for the de novo synthesis of long-chain fatty acids, which play a key role in controlling the activation, differentiation, and function of immune cells. However, the role of FASN in regulating the activations of monocytes/macrophages and DCs has not been studied. In this study, we investigated the involvement of the FASN in modulating the activations of macrophages and DCs, as well as the pathogenesis of SLE. Importantly, we observed a significant upregulation of FASN expression in monocytes and DCs from patients with SLE. This increase is strongly correlated with disease severity and activation status of the immune cells. Furthermore, overexpression of FASN significantly boosts the TLR4/7/9-mediated activation of macrophages and DCs, while knockdown of FASN markedly inhibits this activation. Notably, knockdown of FASN alleviates TLR7 agonist imiquimod (IMQ)-induced lupus in mice and the activation of macrophages and DCs. It makes more sense that pharmaceutical targeting of FASN by using TVB-2640 significantly alleviates IMQ-induced lupus in mice and the activation of macrophages and DCs, as well as in spontaneous lupus MRL/lpr mice. Thus, FASN contributes to the TLRs-mediated activation of macrophages and DCs, as well as the pathogenesis of SLE. More importantly, FASN inhibitor TVB-2640 is expected to be an effective drug in the treatment of SLE.

Trained innate immunity in response to nuclear antigens in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease directed against nuclear antigens, including those derived from apoptotic microparticles (MPs) and neutrophil extracellular traps (NETs). Here we investigated whether nuclear autoantigens can induce trained immunity in SLE patients. Trained immunity is a de facto innate immune memory elicited by an initial stimulus that induces a more vigorous long-term inflammatory response to subsequent stimuli. Isolated monocytes were stimulated with SLE-typical nuclear antigens, neutrophil extracellular traps (NETs), and apoptotic microparticles (MPs) or plasma from SLE patients. After five days of rest, cells were restimulated with Toll-like receptor (TLR) agonists, and cytokine production was measured using ELISA. Functional, transcriptomic and epigenetic changes in monocytes from SLE patients were evaluated by ex vivo stimulations, flow cytometric analysis, RNA sequencing, and chromatin immunoprecipitation (ChIP) sequencing for histone 3 lysine 4 trimethylation. We found that in vitro, both MPs and NETs, as well as plasma from SLE patients, can induce trained immunity. Furthermore, circulating monocytes from SLE patients produce increased levels of pro-inflammatory cytokines after stimulation with TLR ligands, indicating trained immunity. This is accompanied by deregulation in histone 3 lysine 4 trimethylation and increased expression of metabolism and inflammation-related genes. Our findings demonstrate that trained immunity can develop against nuclear antigens and that trained immunity is involved in the immunological dysregulation in SLE patients.

Subchronic intranasal lipopolysaccharide exposure induces pulmonary autoimmunity and glomerulonephritis in NZBWF1 mice

Lupus, a systemic autoimmune disease shaped by gene-environment interplay, often progresses to endstage renal failure. While subchronic systemic exposure to bacterial lipopolysaccharide (LPS) triggers autoimmunity and glomerulonephritis in lupus-prone mice, it is unknown if inhaling LPS, which is common in certain occupations, can similarly trigger lupus. Here we determined how subchronic intranasal (IN) LPS instillation influences autoimmunity and glomerulonephritis development in lupusprone NZBWF1 female mice. Briefly, mice were IN-instilled with vehicle or E. coli LPS (0.8 μg/g) twice weekly for 5 wk, followed by necropsy. For systemic comparison, additional cohorts of mice were injected with LPS intraperitoneally (IP) using identical doses/timing. Lungs were assessed for inflammatory and autoimmune responses and then related to systemic autoimmunity and glomerulonephritis. IN/LPS exposure induced in the lung: i) leukocyte infiltration, ii)mRNA signatures for cytokines, chemokines, IFN-regulated, and cell death-related genes, iii) ectopic lymphoid tissue formation, and iv)diverse IgM and IgG autoantibodies (AAbs). Pulmonary effects coincided with enlarged spleens, elevated plasma IgG AAbs, and inflamed IgG-containing kidney glomeruli. In contrast, IP/LPS treatment induced systemic autoimmunity and glomerulonephritis without pulmonary manifestations. Taken together, these preclinical findings suggest the lung could serve as a critical nexus for triggering autoimmunity by respirable LPS in genetically predisposed individuals.

Partial long-term clinical improvement after a BCG challenge in systemic lupus erythematosus-prone mice

Systemic Lupus Erythematosus (SLE) is an autoimmune disorder that causes a breakdown of immune tolerance. Current treatments mainly involve general immunosuppression, increasing the risk of infections. On the other hand, Bacillus Calmette-Guérin (BCG) has been investigated as a potential therapy for autoimmune diseases in recent years, prompting an ongoing investigation. This study aimed to evaluate the effect of BCG vaccination on early and late clinical presentation of SLE in a murine disease model. MRL/MPJ-Faslpr mice were immunized with BCG or treated with PBS as a control. The progress of the disease was evaluated at 27 days post-immunization (dpi) (early) and 56 dpi (late). Clinical parameters and proteinuria were monitored. Blood samples were collected for measurement of antinuclear antibodies (ANAs), anti-double-stranded DNA (anti-dsDNA), and cytokine determination was performed using ELISA. Samples collected from mice were analyzed by flow cytometry and histopathology. We observed a clinical improvement in BCG-treated mice, reduced proteinuria in the latter stages of the disease, and decreased TNF-α. However, BCG did not elicit significant changes in ANAs, anti-dsDNA, histopathological scores, or immune cell infiltration. BCG was only partially beneficial in an SLE mouse model, and further research is needed to determine whether the immunity induced by this vaccine can counteract lupus's autoimmune response.

Characterization of systemic lupus erythematosus subtypes using cluster analysis: insights from lymphocyte subpopulations

BACKGROUND

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease, in which lymphocyte subsets were dysregulated. Incorporating lymphocyte subpopulations in cluster analysis offers a pathway for personalized and precise treatment, targeting specific abnormalities for more effective management.

METHODS

We conducted Gaussian clustering analysis on clinical data, serological data, urine test results, and lymphocyte subpopulations for SLE patients hospitalized from September 2008 to December 2019.

RESULTS

A total of 1863 SLE patients from Xi'Jing Hospital were included. After excluding those without complete assessments, 1281 patients underwent flow cytometry for lymphocyte subsets. Five SLE clusters emerged: Cluster 1 with severe kidney involvement, high SLEDAI scores, and infection rates, often accompanied by rashes and edema; cluster 2 with high urinary protein but better renal function; cluster 3 with normal lymphocyte count and low positive antibodies; cluster 4 with frequent psychiatric symptoms and pulmonary arterial hypertension (PAH); and cluster 5 with fever, arthritis, hematologic involvement, and high IgG levels despite decreased B cells.

CONCLUSION

All enrolled SLE patients were ultimately categorized into five distinct clinical phenotype groups, with lymphocyte testing being meaningful for patient stratification. This finding shed light on the intricate heterogeneity of SLE, emphasizing the need for a personalized medicine approach. Targeting specific abnormalities in lymphocyte subsets holds promise for more effective and precise management of SLE. Key Points • A comprehensive analysis of SLE patients, including lymphocyte subpopulations, revealed five distinct clusters with varying clinical characteristics, emphasizing the heterogeneity of the disease. • This heterogeneity underscores the need for a personalized medicine approach in SLE management, targeting specific lymphocyte subset abnormalities for more effective and precise treatment.

Association of autoantibodies with the IFN signature and NETosis in patients with systemic lupus erythematosus

Objective

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by a variety of disease symptoms and an unpredictable clinical course. To improve treatment outcome, stratification based on immunological manifestations commonly seen in patients with SLE such as autoantibodies, type I interferon (IFN) signature and neutrophil extracellular trap (NET) release may help. It is assumed that there is an association between these immunological phenomena, since NET release induces IFN production and IFN induces autoantibody formation via B-cell activation. Here we studied the association between autoantibodies, the IFN signature, NET release, and clinical manifestations in patients with SLE.

Methods

We performed principal component analysis (PCA) and hierarchical clustering of 57 SLE-related autoantibodies in 25 patients with SLE. We correlated each autoantibody to the IFN signature and NET inducing capacity.

Results

We observed two distinct clusters: one cluster contained mostly patients with a high IFN signature. Patients in this cluster often present with cutaneous lupus, and have higher anti-dsDNA concentrations. Another cluster contained a mix of patients with a high and low IFN signature. Patients with high and low NET inducing capacity were equally distributed between the clusters. Variance between the clusters is mainly driven by antibodies against histones, RibP2, RibP0, EphB2, RibP1, PCNA, dsDNA, and nucleosome. In addition, we found a trend towards increased concentrations of autoantibodies against EphB2, RibP1, and RNP70 in patients with an IFN signature. We found a negative correlation of NET inducing capacity with anti-FcER (r = -0.530; p = 0.007) and anti-PmScl100 (r = -0.445; p = 0.03).

Conclusion

We identified a subgroup of patients with an IFN signature that express increased concentrations of antibodies against DNA and RNA-binding proteins, which can be useful for further patient stratification and a more targeted therapy. We did not find positive associations between autoantibodies and NET inducing capacity. Our study further strengthens the evidence of a correlation between RNA-binding autoantibodies and the IFN signature.

Multiple-dose pharmacokinetics of cenerimod and the effect of charcoal on its elimination

Cenerimod is a sphingosine-1-phosphate receptor 1 modulator that reduces tissue availability of circulating lymphocytes. The compound is in Phase 3 development for the treatment of systemic lupus erythematosus. Its pharmacokinetic properties are characterized by slow absorption and multiphasic elimination with a long terminal half-life (t½), potentially caused by enterohepatic circulation (EHC). In this trial in healthy participants, oral cenerimod 0.5 and 4 mg once daily was administered for 50 days, followed by oral administration of activated charcoal (ie, 50 mg every 12 h for 11 days, starting 24 h after the last cenerimod dose), to investigate the potential EHC of cenerimod and assess whether elimination of cenerimod can be accelerated. The multiple-dose pharmacokinetics, pharmacodynamics, safety, and tolerability of cenerimod were also evaluated. For both doses, peak plasma concentrations were reached 6 and 7 h after dosing. Cenerimod accumulated approximately eightfold and (near) steady-state conditions were reached after 50 doses, resembling clinically meaningful exposure to cenerimod. The t½ following 0.5 and 4 mg of cenerimod was 767 and 799 h (ie, 32 and 33 days) and 720 and 780 h (ie, 30 and 33 days) with or without administration of charcoal, respectively, indicating no statistically significant difference. Therefore, charcoal did not accelerate cenerimod elimination suggesting that there is no EHC of cenerimod. A reversible, dose-dependent decrease in total lymphocyte count was observed. No safety concerns were identified; administration of charcoal was well tolerated.

Double-filtration plasmapheresis reduces type I interferon bioavailability and inducing activity in systemic lupus erythematosus

Type I interferons (IFN-Is) play a significant role in systemic lupus erythematosus (SLE) pathogenesis. Double-filtration plasmapheresis (DFPP) is a treatment option for SLE; however, its effect on IFN-Is remains unclear. Therefore, we investigated the effects of DFPP on IFN-Is. Plasma from patients with SLE (n = 11) who regularly underwent DFPP was analysed using a cell-based reporter system to detect the bioavailability and inducing activity of IFN-I. The concentration of plasma dsDNA was measured, and western blotting analysis was used to assess the phosphorylation of the STING pathway. A higher IFN-I bioavailability and inducing activity were observed in patients compared to healthy controls, and both parameters decreased after DFPP. The reduction in IFN-I-inducing activity was particularly prominent in patients with high disease activity. Notably, this reduction was not observed in STING-knockout reporter cells. Additionally, plasma dsDNA levels decreased after DFPP treatment, suggesting that inhibition of the STING pathway was responsible for the observed decrease in activity. Western blotting analysis revealed suppression of STING pathway phosphorylation after DFPP. DFPP reduced IFN-I bioavailability and the inducing activity of plasma. This reduction is likely attributable to the inhibition of the STING pathway through the elimination of dsDNA.

Brain-immune interactions: implication for cognitive impairments in Alzheimer's disease and autoimmune disorders

Progressive memory loss and cognitive dysfunction, encompassing deficits in learning, memory, problem solving, spatial reasoning, and verbal expression, are characteristics of Alzheimer's disease and related dementia. A wealth of studies has described multiple roles of the immune system in the development or exacerbation of dementia. Individuals with autoimmune disorders can also develop cognitive dysfunction, a phenomenon termed "autoimmune dementia." Together, these findings underscore the pivotal role of the neuroimmune axis in both Alzheimer's disease and related dementia and autoimmune dementia. The dynamic interplay between adaptive and innate immunity, both in and outside the brain, significantly affects the etiology and progression of these conditions. Multidisciplinary research shows that cognitive dysfunction arises from a bidirectional relationship between the nervous and immune systems, though the specific mechanisms that drive cognitive impairments are not fully understood. Intriguingly, this reciprocal regulation occurs at multiple levels, where neuronal signals can modulate immune responses, and immune system-related processes can influence neuronal viability and function. In this review, we consider the implications of autoimmune responses in various autoimmune disorders and Alzheimer's disease and explore their effects on brain function. We also discuss the diverse cellular and molecular crosstalk between the brain and the immune system, as they may shed light on potential triggers of peripheral inflammation, their effect on the integrity of the blood-brain barrier, and brain function. Additionally, we assess challenges and possibilities associated with developing immune-based therapies for the treatment of cognitive decline.

Chimeric antigen receptor T-cell therapy in autoimmune diseases

The administration of T cells that have been modified to carry chimeric antigen receptors (CARs) aimed at B cells has been an effective strategy in treating B cell malignancies. This breakthrough has spurred the creation of CAR T cells intended to specifically reduce or alter the faulty immune responses associated with autoimmune disorders. Early positive outcomes from clinical trials involving CAR T cells that target the B cell protein CD19 in patients suffering from autoimmune diseases driven by B cells have been reported. Additional strategies are being developed to broaden the use of CAR T cell therapy and enhance its safety in autoimmune conditions. These include employing chimeric autoantireceptors (CAAR) to specifically eliminate B cells that are reactive to autoantigens, and using regulatory T cells (Tregs) engineered to carry antigen-specific CARs for precise immune modulation. This discussion emphasizes key factors such as choosing the right target cell groups, designing CAR constructs, defining tolerable side effects, and achieving a lasting immune modification, all of which are critical for safely integrating CAR T cell therapy in treating autoimmune diseases.

Differential lncRNA profiles of blood plasma-derived exosomes from systemic lupus erythematosus

INTRODUCTION

Long non-coding RNAs (lncRNAs) dysregulation is key in the pathogenesis of systemic lupus erythematosus (SLE), but the role of exosomal lncRNAs in SLE has not been well studied. We elucidated the profiles of plasma exosomal lncRNAs expression in patients with SLE and predictd their potential clinical significance in SLE.

METHODS

In the screening stage, six newly diagnosed and untreated patients with SLE and six healthy controls were examined by high-throughput sequencing technology, and differential exosomal lncRNA profiles were constructed. In the validation phase, two differentially selected exosomal lncRNAs from 20 patients each with active and stable SLE and 20 healthy controls were verified with RT-qPCR. The correlation between the selected exosomal lncRNAs and SLE clinical indicators was examined. The diagnostic value of the selected exosomal lncRNAs in SLE was analyzed by the receiver operator characteristic (ROC) curve.

RESULTS

Exosomes were successfully extracted from the patients and controls. Sequencing-phase sequencing demonstrated 528 upregulated lncRNAs and 7491 downregulated lncRNAs. In the validation stage, exosomal LINC00667 and DANCR were significantly upregulated in the patients, and positively correlated with Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2 K). Exosomal DANCR expression between the active and stable SLE patients was different. The area under the curve(AUC) of exosomal LINC00667 and DANCR for SLE diagnosis was 0.815 and 0.759, respectively.

CONCLUSIONS

Exosomal LINC00667 and DANCR were upregulated in SLE, and might be new biomarkers thereof. Exosomal DANCR was associated with SLE activity.

A review on the novel biomarkers of systemic lupus erythematosus discovered via metabolomic profiling

Systemic lupus erythematosus (SLE) is a multifaceted autoimmune disease affecting various body organs and systems. The diagnosis of SLE and its complications is based on evident clinical symptoms, serological marker levels, and pathological findings. Some serological markers have a low sensitivity and specificity, and biopsy procedures are invasive in nature. Hence, metabolomics has emerged as a valuable tool for SLE screening and categorization. Its application has contributed significantly to identifying SLE pathogenesis, improving clinical diagnosis, and developing treatment approaches. This review provides an overview of the utilization of metabolomics in the study of SLE, focusing on advancements in understanding the disease's pathogenesis, aiding in diagnosis, and monitoring treatment efficacy.

Upregulation of granzyme B and C-X3-C motif receptor 1 in circulating plasmablasts was negatively regulated by Notch signal in patients with systemic lupus erythematosus

As one molecule related to cytotoxicity, surface expression of C-X3-C motif receptor 1 (CX3CR1) was highly correlated with intracellular granzyme B (GZMB) in natural killer and cytolytic T cells. However, the expression of CX3CR1 and GZMB in B cells has not been clarified, and their clinical significance in systemic lupus erythematosus (SLE) remains unclear. This study aimed to clarify the changes and clinical significance of peripheral blood B cells expressing GZMB and/or CX3CR1 in SLE. Peripheral blood was collected from 39 patients with SLE and 48 healthy controls. We found that GZMB and CX3CR1 expression varied in different B-cell subsets, with plasmablasts possessing the highest positive percentages, consistent with bioinformatics prediction. GZMB+ and CX3CR1+ percentages in circulating B cells and plasmablasts were increased in patients with SLE. CX3CR1 was upregulated on B cells after in vitro stimulation. Notch intracellular domain expression was significantly decreased in plasmablasts of patients with SLE, and CX3CR1 in plasmablasts was downregulated with the addition of JAG1. In conclusion, GZMB and CX3CR1 were increased in B cells and in plasmablasts of patients with SLE and CX3CR1 was negatively regulated by Notch signal in plasmablasts, which may be involved in SLE pathogenesis.

The safety and efficacy of Baricitinib for systemic lupus erythematosus: a systematic review and meta-analysis of randomized controlled trials

Background and objective

Baricitinib is a JAK1 and JAK2 inhibitor approved for treating active rheumatoid arthritis and atopic dermatitis. Therefore, the authors aim to evaluate the safety and efficacy of once-daily oral Baricitinib 2 mg or 4 mg versus placebo in active SLE patients receiving standard care.

Methods

The authors synthesized randomized controlled studies (RCTs) from MEDLINE, Scopus, EMBASE, PubMed, and Cochrane Library until 20 March 2023. The study protocol was registered in PROSPERO.

Results

Three RCTs with 1849 participants were included. The Baricitinib group had a significant SRI-4 response [RR: 1.11 with 95% CI (1.03, 1.21), P=0.008] and greater than or equal to 4-point SLEDAI-2K domain improvement [RR: 1.13 with 95% CI (1.02, 1.25), P=0.02] compared to the placebo group; however, there was no statistically significant difference between the two groups, regarding the secondary endpoints. For safety outcomes, Baricitinib was significantly associated with a higher incidence of Any serious adverse event [RR: 1.48 with 95% CI (1.07, 2.05), P=0.02].

Conclusion

Baricitinib is associated with significant outcomes of SRI-4 response, greater than or equal to 4-point improvement SLEDAI-2K score, and Joint Indices. Regarding safety, there was no difference in the outcomes other than the serious adverse events.

Pathogenic role of anti-nuclear autoantibodies in systemic sclerosis: Insights from other rheumatic diseases

Systemic sclerosis (SSc) is a severe autoimmune disease characterized by vasculopathy, fibrosis, and dysregulated immunity, with hallmark autoantibodies targeting nuclear antigens such as centromere protein (ACA) and topoisomerase I (ATA). These autoantibodies are highly prevalent and disease-specific, rarely coexisting, thus serving as crucial biomarkers for SSc diagnosis. Despite their diagnostic value, their roles in SSc pathogenesis remain unclear. This review summarizes current literature on ACA and ATA in SSc, comparing them to autoantibodies in other rheumatic diseases to elucidate their potential pathogenic roles. Similarities are drawn with anti-citrullinated protein antibodies (ACPA) in rheumatoid arthritis, particularly regarding disease specificity and minimal pathogenic impact of antigen binding. In addition, differences between ANA and ACPA in therapeutic responses and Fab glycosylation patterns are reviewed. While ACA and ATA are valuable for disease stratification and monitoring activity, understanding their origins and the associated B cell responses is critical for advancing therapeutic strategies for SSc.

[Current patient care of systematic lupus erythematosus in Rhineland-Palatinate and Saarland]

BACKGROUND

Systemic lupus erythematosus (SLE) is a clinically heterogeneous autoimmune disease that is associated with great suffering for those affected, as well as high socioeconomic costs. Early diagnosis and adequate medical care are essential for a mild course of the disease. However, there is a lack of current figures and data on the care situation of patients in the area.

METHODOLOGY

A total of 1546 general practitioners, rheumatologists, neurologists, nephrologists and dermatologists in Rhineland-Palatinate and Saarland were interviewed by fax or mail using a questionnaire regarding epidemiology, symptoms, therapy and therapy success. In addition, there was the possibility of making suggestions for improvement.

RESULTS

Five out of six of the 635 reported SLE patients were female. The most common main symptoms were arthralgia, fatigue, myalgia, and skin changes. Of the patients, 68% received antimalarials (AMs), whereas 46% were treated with glucocorticoids (GCs) and 50% with an immunosuppressant (IS), mainly methotrexate. In terms of comorbidities, patients suffered mainly from cardiovascular disease, fibromyalgia syndrome and depression. Rheumatologists also frequently described anaemia, diabetes mellitus and osteoporosis.

DISCUSSION

Compared with guideline recommendations, the low rate of AMs in therapy was particularly striking in patients not treated by rheumatologists (35% on average compared with 81% for rheumatologists). Additionally, (sustained) high doses of GCs are not in line with literature recommendations. In the free text field, the main requests were for more rheumatologists in private practice and faster appointment scheduling, as well as better communication and networking. In addition, the desire for more training and education was frequently expressed..

Systemic lupus erythematosus: pathogenesis and targeted therapy

Systemic lupus erythematosus (SLE) is a multifaceted autoimmune disorder characterized by dysregulated immune responses and autoantibody production, which affects multiple organs and varies in clinical presentation and disease severity. The development of SLE is intricate, encompassing dysregulation within the immune system, a collapse of immunological tolerance, genetic susceptibilities to the disease, and a variety of environmental factors that can act as triggers. This review provides a comprehensive discussion of the pathogenesis and treatment strategies of SLE and focuses on the progress and status of traditional and emerging treatment strategies for SLE. Traditional treatment strategies for SLE have mainly employed non-specific approaches, including cytotoxic and immunosuppressive drugs, antimalarials, glucocorticoids, and NSAIDs. These strategies are effective in mitigating the effects of the disease, but they are not a complete cure and are often accompanied by adverse reactions. Emerging targeted therapeutic drugs, on the other hand, aim to control and treat SLE by targeting B and T cells, inhibiting their activation and function, as well as the abnormal activation of the immune system. A deeper understanding of the pathogenesis of SLE and the exploration of new targeted treatment strategies are essential to advance the treatment of this complex autoimmune disease.

Advances in the study of artemisinin and its derivatives for the treatment of rheumatic skeletal disorders, autoimmune inflammatory diseases, and autoimmune disorders: a comprehensive review

Artemisinin and its derivatives are widely recognized as first-line treatments for malaria worldwide. Recent studies have demonstrated that artemisinin-based antimalarial drugs, such as artesunate, dihydroartemisinin, and artemether, not only possess excellent antimalarial properties but also exhibit antitumor, antifungal, and immunomodulatory effects. Researchers globally have synthesized artemisinin derivatives like SM735, SM905, and SM934, which offer advantages such as low toxicity, high bioavailability, and potential immunosuppressive properties. These compounds induce immunosuppression by inhibiting the activation of pathogenic T cells, suppressing B cell activation and antibody production, and enhancing the differentiation of regulatory T cells. This review summarized the mechanisms by which artemisinin and its analogs modulate excessive inflammation and immune responses in rheumatic and skeletal diseases, autoimmune inflammatory diseases, and autoimmune disorders, through pathways including TNF, Toll-like receptors, IL-6, RANKL, MAPK, PI3K/AKT/mTOR, JAK/STAT, and NRF2/GPX4. Notably, in the context of the NF-κB pathway, artemisinin not only inhibits NF-κB expression by disrupting upstream cascades and/or directly binding to NF-κB but also downregulates multiple downstream genes controlled by NF-κB, including inflammatory chemokines and their receptors. These downstream targets regulate various immune cell functions, apoptosis, proliferation, signal transduction, and antioxidant responses, ultimately intervening in systemic autoimmune diseases and autoimmune responses in organs such as the kidneys, nervous system, skin, liver, and biliary system by modulating immune dysregulation and inflammatory responses. Ongoing multicenter randomized clinical trials are investigating the effects of these compounds on rheumatic, inflammatory, and autoimmune diseases, with the aim of translating promising preclinical data into clinical applications.

Serum HMGB-1 released by ferroptosis and necroptosis as a novel potential biomarker for systemic lupus erythematosus

High mobility group box proterin-1 (HMGB-1) is a multifunctional protein that can be released by various programmed cell deaths (PCDs), such as necroptosis and ferroptosis. PCDs play a critical role in the pathogenesis of systemic lupus erythematosus (SLE). However, the role of HMGB-1 in the process of SLE remains unclear. This study aims to demonstrate the potential diagnosing role of serum HMGB-1 in SLE that released by necroptosis and ferroptosis. We found that the serum levels of HMGB-1, receptor-interacting protein kinase 3 (RIPK3) /mixed lineage kinase domain-like protein (MLKL) related with necroptosis, and metabolites associated with ferroptosis were significantly upregulated in SLE patients compared to HC individuals. These serum levels were positively correlated with SLE disease activity. Additionally, the serum level of HMGB-1 showed a strong positive correlated with the levels of RIPK3/MLKL and ferroptosis metabolites. Moreover, the serum level of HMGB-1 was correlated with renal involvement and high-antinuclear antibodies (ANA) titer. After SLE serum and interferon γ (IFN-γ) treatment in vitro, the level of necroptosis and ferroptosis markers were activated and HMGB1 was released both in HEK293 and HK2 cells. Clinically, HMGB-1 was considered as a significant independent risk factor in SLE serum by binary logistic assay. Notably, HMGB-1 exhibited outstanding diagnostic ability for SLE by the area under the curve (AUC) in receiver operating characteristic (ROC) curve analysis. Taken together, our study indicates that the serum level of HMGB-1 is a promising biomarker for the diagnosis and monitoring of SLE.

Is Idiopathic Granulomatous Mastitis a Subgroup of Systemic Lupus Erythematosus? A Preliminary Study

Objective: The study aimed to use the systemic lupus erythematosus risk probability index (SLERPI) to assess if patients with idiopathic granulomatous mastitis (IGM) meet the criteria for systemic lupus erythematosus (SLE). Methods: A total of 62 patients with IGM and 55 age- and sex-matched healthy controls (HC) were enrolled. The study included patients who were over 18 years old and had been diagnosed with IGM using a true-cut biopsy. The participants' demographic, clinical, and laboratory data were recorded in detail. The presence of autoantibodies, such as RF, CCP, C3, C4, ANA, ENA profile, and Anti-dsDNA was documented. For the detection of SLE in IGM patients, we used the SLERPI (SLE risk probability index). Results: A total of 62 patients diagnosed with idiopathic granulomatous mastitis (age 35.22 ± 8.34, BMI 27.15 ± 3.41) were compared to 55 healthy controls (age 32.54 ± 8.67, BMI 26.97 ± 3.54). The present study assessed the performance of SLERPI in IGM, and SLERPI positivity was observed in 12 out of 62 (19.4%) IGM patients. There was a significant difference in arthritis and ANA levels in the SLERPI subgroups (p < 001). Conclusions: The SLERPI index can be utilized to identify patients suspected of having systemic lupus erythematosus (SLE) in the IGM cohort.

Blood Growth Factor Levels in Patients with Systemic Lupus Erythematosus: High Neuregulin-1 Is Associated with Comorbid Cardiovascular Pathology

Patients with systemic lupus erythematosus (SLE) are known to frequently suffer from comorbid cardiovascular diseases (CVDs). There are abundant data on cytokine levels and their role in the pathogenesis of SLE, while growth factors have received much less attention. The aim of this study was to analyze growth factor levels in SLE patients and their association with the presence of comorbid CVDs. The serum concentrations for the granulocyte-macrophage colony-stimulating factor (GM-CSF), nerve growth factor β (NGFβ), glial cell line-derived neurotrophic factor (GDNF), and neuregulin-1 β (NRG-1β) were determined in the SLE patients (n = 35) and healthy individuals (n = 38) by a Luminex multiplex assay. The NGFβ and NRG-1β concentrations were shown to be significantly higher in the total group of SLE patients (median [Q1-Q3]: 3.6 [1.3-4.5] and 52.5 [8.5-148], respectively) compared with the healthy individuals (2.9 [1.3-3.4] and 13.7 [4.4-42] ng/mL, respectively). The GM-CSF and GDNF levels did not differ. Interestingly, elevated NRG-1β levels were associated with the presence of CVDs, as SLE patients with CVDs had significantly higher NRG-1β levels (99 [22-242]) compared with the controls (13.7 [4.4-42]) and patients without CVDs (19 [9-80] ng/mL). The model for the binary classification of SLE patients with and without CVDs based on the NRG-1β level had an average predictive ability (AUC = 0.67). Thus, altered levels of growth factors may be associated with comorbid CVDs in SLE patients.

Caffeine improves systemic lupus erythematosus endothelial dysfunction by promoting endothelial progenitor cells survival

OBJECTIVE

We studied the role of caffeine intake on endothelial function in SLE by assessing its effect on circulating endothelial progenitor cells (EPCs) both ex vivo in SLE patients and in vitro in healthy donors (HD) treated with SLE sera.

METHODS

We enrolled SLE patients without traditional cardiovascular risks factors. Caffeine intake was evaluated with a 7-day food frequency questionnaire. EPCs percentage was assessed by flow cytometry analysis and, subsequently, EPCs pooled from six HD were co-cultured with caffeine with and without SLE sera. After 7 days, we evaluated cells' morphology and ability to form colonies, the percentage of apoptotic cells by flow cytometry analysis and the levels of autophagy and apoptotic markers by western blot. Finally, we performed a western blot analysis to assess the A2AR/SIRT3/AMPK pathway.

RESULTS

We enrolled 31 SLE patients, and observed a positive correlation between caffeine intake and circulating EPCs percentage. HD EPCs treated with SLE sera and caffeine showed an improvement in morphology and in number of EPCs colony-forming units in comparison with those incubated without caffeine. Caffeine was able to restore autophagy and apoptotic markers in HD EPCs as before SLE sera treatment. Finally, caffeine treatment was able to significantly reduce A2AR levels, leading to an increase in protein levels of SIRT3 and subsequently AMPK phosphorylation.

CONCLUSIONS

Caffeine intake positively correlated with the percentage of circulating EPCs in SLE patients; moreover, caffeine in vitro treatment was able to improve EPC survival and vitality through the inhibition of apoptosis and the promotion of autophagy via A2AR/SIRT3/AMPK pathway.

Evaluation of survivin expression and regulating miRNAs of survivin expression in peripheral blood mononuclear cells in systemic lupus erythematous patients

BACKGROUND

Systemic lupus erythematosus is a multisystemic rheumatic disease with different clinical features. Disturbance in apoptosis regulation seems to be a major factor in SLE development.

OBJECTIVE

Survivin plays a key role in mitosis and inhibiting apoptosis. A study was conducted to examine the expression level of survivin and miRNAs that affect survivin transcript levels in patients with SLE.

METHODS

We isolated peripheral blood mononuclear cells from 50 inactive SLE patients and 50 healthy controls. RNA is extracted and converted to cDNA. The quantitative real-time polymerase chain reaction is conducted to assess the expression levels of survivin total and its variants with effective miRNAs in PBMCs.

RESULTS

Expression levels of miR-34a-5p (fold change = 1.5, p++ = 0.027), and 218-5p (fold change = 1.5, p++ = 0.020) were significantly increased. While miR-150-5p (fold change = 0.56, p++ = 0.003) was significantly decreased. The mRNA expression of survivin-WT (fold change = 0.63, p++ = 0.002) was significantly downregulated in SLE patients compared to the healthy controls. Survivin total and its two major variants (survivin-2B, and survivin-ΔEx3) did not differ significantly between SLE patients and controls.

CONCLUSION

Although survivin-TS and its two variants (survivin-2B, and survivin-ΔEx3) were not differently expressed in SLE patients, survivin-WT had altered expression. Despite aberrant miRNA expression in PBMCs from SLE patients, survivin and miRNA expression were not associated with leukopenia. The pathogenesis of SLE disorder might be linked to survivin's other roles in the immune system aside from anti-apoptotic functions.

Biomarkers for systemic lupus erythematosus: A scoping review

BACKGROUND

In recent years, newly discovered potential biomarkers have great research potential in the diagnosis, disease activity prediction, and treatment of systemic lupus erythematosus (SLE).

OBJECTIVE

In this study, a scoping review of potential biomarkers for SLE over several years has identified the extent to which studies on biomarkers for SLE have been conducted, the specificity, sensitivity, and diagnostic value of potential biomarkers of SLE, the research potential of these biomarkers in disease diagnosis, and activity detection is discussed.

METHODS

In PubMed and Google Scholar databases, "SLE," "biomarkers," "predictor," "autoimmune diseases," "lupus nephritis," "neuropsychiatric SLE," "diagnosis," "monitoring," and "disease activity" were used as keywords to systematically search for SLE molecular biomarkers published from 2020 to 2024. Analyze and summarize the literature that can guide the article.

CONCLUSIONS

Recent findings suggest that some potential biomarkers may have clinical application prospects. However, to date, many of these biomarkers have not been subjected to repeated clinical validation. And no single biomarker has sufficient sensitivity and specificity for SLE. It is not scientific to choose only one or several biomarkers to judge the complex disease of SLE. It may be a good direction to carry out a meta-analysis of various biomarkers to find SLE biomarkers suitable for clinical use, or to evaluate SLE by combining multiple biomarkers through mathematical models. At the same time, advanced computational methods are needed to analyze large data sets and discover new biomarkers, and strive to find biomarkers that are sensitive and specific enough to SLE and can be used in clinical practice, rather than only staying in experimental research and data analysis.

Lipocalin-2 drives neuropsychiatric and cutaneous disease in MRL/lpr mice

Introduction

Approximately 20-40% of patients with systemic lupus erythematosus (SLE) experience neuropsychiatric SLE (NPSLE), which often manifests as cognitive dysfunction and depression. Currently, there are no approved treatments for NPSLE because its underlying mechanisms are unclear. Identifying relevant mediators and understanding their contribution to pathogenesis are crucial for developing targeted treatment options. Lipocalin 2 (LCN2) is a multifunctional acute-phase protein that plays important roles in immune cell differentiation, migration, and function. LCN2 has been implicated in models of neuroinflammatory disease.

Methods

We generated an LCN2-deficient MRL/lpr mouse to evaluate the effects of LCN2 on this classic NPSLE model. To evaluate the effects of LCN2 deficiency on behavior, the mice underwent a battery of behavioral tests evaluating depression, memory, and anxiety. Flow cytometry was used to quantify immune cell populations in the brain, blood, and secondary lymphoid organs. Cutaneous disease was quantified by scoring lesional skin, and skin infiltrates were quantified through immunofluorescent staining. Systemic disease was evaluated through measuring anti-nuclear antibodies by ELISA.

Results

In this study, we found that LCN2 deficiency significantly attenuates neuropsychiatric and cutaneous disease in MRL/lpr lupus prone mice, likely by decreasing local infiltration of immune cells into the brain and skin and reducing astrocyte activation in the hippocampus. Anti-nuclear antibodies and kidney disease were not affected by LCN2.

Discussion

As there was no effect on systemic disease, our results suggest that the inflammatory effects of LCN2 were localized to the skin and brain in this model. This study further establishes LCN2 as a potential target to ameliorate organ injury in SLE, including neuropsychiatric and cutaneous disease.

Anti-vasodilator-stimulated phosphoprotein (VASP) antibodies are associated with neuropsychiatric disorders in systemic lupus erythematosus

Background

Systemic lupus erythematosus (SLE) is a complex autoimmune disease characterized by multi-organ involvement and the presence of autoantibodies, pathogenic factors that can serve as diagnostic biomarkers. The current research has been focusing on exploring specific autoantigens with clinical relevance for SLE subtypes. In line with this objective, this study investigated potential antigenic targets associated with specific phenotypes in SLE by leveraging an omics-based approach combined with immunoassay techniques.

Methods

A transcriptomic analysis was conducted in a cohort of 70 SLE patients to identify genes significantly correlated to the relevant phenotype. Epitope mapping and sequence analysis techniques were used to predict autoantigens, and the corresponding antibodies were subsequently quantified by enzyme-linked immunosorbent assay (ELISA) and validated by Western blot.

Results

Transcriptomic data analysis revealed a group of hub genes exhibiting a significant correlation with the neuropsychiatric phenotype and a positive relationship with platelets. Subsequent epitope prediction for the corresponding proteins highlighted vasodilator-stimulated phosphoprotein (VASP) as a potential autoantigen. Moreover, ELISA and immunoblotting confirmed that the anti-VASP antibody present in the serum was significantly elevated in SLE patients with neuropsychiatric involvement and positively associated with demyelination.

Conclusion

VASP harbors autoantigenic epitopes associated with neuropsychiatric phenotype, especially the demyelination symptom in SLE, and its antibodies may serve as promising biomarkers in this disease.

Diagnosis of neuropsychiatric systemic lupus erythematosus by label-free serum microsphere-coupled SERS fingerprints with machine learning

Surface-enhanced Raman spectroscopy (SERS) is a powerful optical technique for non-invasive and label-free bioanalysis of liquid biopsy, facilitating to diagnosis of potential diseases. Neuropsychiatric systemic lupus erythematosus (NPSLE) is one of the subgroups of systemic lupus erythematosus (SLE) with serious manifestations for a high mortality rate. Unfortunately, lack of well-established gold standards results in the clinical diagnosis of NPSLE being a challenge so far. Here we develop a novel Raman fingerprinting machine learning (ML-) assisted diagnostic method. The microsphere-coupled SERS (McSERS) substrates are employed to acquire Raman spectra for analysis via convolutional neural network (CNN). The McSERS substrates demonstrate better performance to distinguish the Raman spectra from serums between SLE and NPSLE, attributed to the boosted signal-to-noise ratio of Raman intensities due to the multiple optical regulation in microspheres and AuNPs. Eight statistically-significant (p-value <0.05) Raman shifts are identified, for the first time, as the characteristic spectral markers. The classification model established by CNN algorithm demonstrates 95.0% in accuracy, 95.9% in sensitivity, and 93.5% in specificity for NPSLE diagnosis. The present work paves a new way achieving clinical label-free serum diagnosis of rheumatic diseases by enhanced Raman fingerprints with machine learning.

Pharmacological Mechanism of Chinese Medicine in Systemic Lupus Erythematosus: A Narrative Review

Systemic lupus erythematosus (SLE) is a chronic autoimmune disorder affecting multiple systems, characterized by the development of harmful autoantibodies and immune complexes that lead to damage in organs and tissues. Chinese medicine (CM) plays a role in mitigating complications, enhancing treatment effectiveness, and reducing toxicity of concurrent medications, and ensuring a safe pregnancy. However, CM mainly solves the disease comprehensively through multi-target and multi-channel regulation process, therefore, its treatment mechanism is often complicated, involving many molecular links. This review introduces the research progress of pathogenesis of SLE from the aspects of genetics, epigenetics, innate immunity and acquired immunity, and then discusses the molecular mechanism and target of single Chinese herbal medicine and prescription that are commonly used and effective in clinic to treat SLE.

Epidemiologic and genetic associations between primary biliary cholangitis and extrahepatic rheumatic diseases

Patients with primary biliary cholangitis (PBC) commonly experience extrahepatic rheumatic diseases. However, the epidemiologic and genetic associations as well as causal relationship between PBC and these extrahepatic conditions remain undetermined. In this study, we first conducted systematic review and meta-analyses by analyzing 73 studies comprising 334,963 participants across 17 countries and found strong phenotypic associations between PBC and rheumatic diseases. Next, we utilized large-scale genome-wide association study summary data to define the shared genetic architecture between PBC and rheumatic diseases, including rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), systemic sclerosis (SSc) and Sjögren's syndrome (SS). We observed significant genetic correlations between PBC and each of the four rheumatic diseases. Pleiotropy and heritability enrichment analysis suggested the involvement of humoral immunity and interferon-associated processes for the comorbidity. Of note, we identified four variants shared between PBC and RA (rs80200208), SLE (rs9843053), and SSc (rs27524, rs3873182) using cross-trait meta-analysis. Additionally, several pleotropic loci for PBC and rheumatic diseases were found to share causal variants with gut microbes possessing immunoregulatory functions. Finally, Mendelian randomization revealed consistent evidence for a causal effect of PBC on RA, SLE, SSc, and SS, but no or inconsistent evidence for a causal effect of extrahepatic rheumatic diseases on PBC. Our study reveals a profound genetic overlap and causal relationships between PBC and extrahepatic rheumatic diseases, thus providing insights into shared biological mechanisms and novel therapeutic interventions.

Unique Interplay Between Antinuclear Antibodies and Nuclear Molecules in the Pathogenesis of Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a prototypic autoimmune disease that primarily affects young women and causes a wide range of inflammatory manifestations. The hallmark of SLE is the production of antibodies to components of the cell nucleus (antinuclear antibodies [ANAs]). These antibodies can bind to DNA, RNA, and protein complexes with nucleic acids. Among ANAs, antibodies to DNA (anti-DNA) are markers for classification and disease activity, waxing and waning disease activity in many patients. In the blood, anti-DNA antibodies can bind to DNA to form immune complexes with two distinct roles in pathogenesis: (1) renal deposition to provoke nephritis and (2) stimulation of cytokine production following uptake into innate immune cells and interaction with internal nucleic acid sensors. These sensors are part of an internal host defense system in the cell cytoplasm that can respond to DNA from infecting organisms; during cell stress, DNA from nuclear and mitochondrial sources can also trigger these sensors. The formation of immune complexes requires a source of extracellular DNA in an immunologically accessible form. As shown in in vivo and in vitro systems, extracellular DNA can emerge from dead and dying cells in both a free and a particulate form. Neutrophils undergoing the process of NETosis can release DNA in mesh-like structures called neutrophil extracellular traps. In SLE, therefore, the combination of ANAs and immunologically active DNA can create new structures that can promote inflammation throughout the body as well as drive organ inflammation and damage.

Predicting autoimmune diseases: A comprehensive review of classic biomarkers and advances in artificial intelligence

Autoimmune diseases comprise a spectrum of disorders characterized by the dysregulation of immune tolerance, resulting in tissue or organ damage and inflammation. Their prevalence has been on the rise, significantly impacting patients' quality of life and escalating healthcare costs. Consequently, the prediction of autoimmune diseases has recently garnered substantial interest among researchers. Despite their wide heterogeneity, many autoimmune diseases exhibit a consistent pattern of paraclinical findings that hold predictive value. From serum biomarkers to various machine learning approaches, the array of available methods has been continuously expanding. The emergence of artificial intelligence (AI) presents an exciting new range of possibilities, with notable advancements already underway. The ultimate objective should revolve around disease prevention across all levels. This review provides a comprehensive summary of the most recent data pertaining to the prediction of diverse autoimmune diseases and encompasses both traditional biomarkers and the latest innovations in AI.

Childhood-onset systemic lupus erythematosus: A descriptive and comparative study of clinical, laboratory, and treatment characteristics in two populations

OBJECTIVE

The aim of this study was to characterize childhood-onset systemic lupus erythematosus (SLE) in two large cohorts from Turkey and the United States.

METHODS

Patients diagnosed with childhood-onset SLE who fulfilled the 1997 American College of Rheumatology classification criteria for SLE from four reference centers in Turkey and the University of Pittsburgh School of Medicine in the United States were included in this study. A comparative analysis was conducted to evaluate the similarities and differences in clinical and laboratory features, damage accrual, and treatment experiences between the two populations.

RESULTS

A total of 174 patients with childhood-onset SLE were included in this study (108 patients from Turkey and 66 patients from the United States). The female-to-male ratio was similar between the two cohorts (∼3:1, p = .73). The median age at diagnosis was 11.67 years (2.19-17.93) in the Turkish cohort and 13.68 years (2.74-17.93) in the U.S. cohort (p < .001). Photosensitivity (45.4% and 21.2%; p = .007) and renal involvement (41.7% and 36.4%; p = .045) were higher in the Turkish cohort. Anti-Ro/SSA (34.8% and 15.7%; p < .001), anti-Sm (59.1% and 19.4%; p < .001), and anti-RNP (47.0% and 14.8%; p < .001) positivity was more frequent in the U.S. cohort. Current use of rituximab (37.9% and 1.9%; p < .001) and belimumab (19.7% and 0%; p < .001) was more prevalent in the U.S. cohort, while the use of cyclophosphamide (often according to the low dose Euro-Lupus protocol) throughout the disease course (24.1% and 4.5%; p < .001) was more frequent in the Turkish cohort. SLICC/ACR Damage Index scores were not different between the two cohorts.

CONCLUSION

This study provides detailed clinical and laboratory features of childhood-onset SLE in two independent and geographically divergent cohorts. Our findings suggest an earlier age of disease onset and a higher prevalence of kidney involvement in Turkish patients. Differences in treatment approaches were also noted. However, damage accrual related to SLE does not appear to be different between the two patient populations.

Rare Turner syndrome and lupus coexistence with insights from DNA methylation patterns

Systemic lupus erythematosus (SLE or lupus) is a complex autoimmune disease that can affect multiple organs. While the exact disease etiology remains incompletely understood, there is a suggested influence of X-chromosome dosage in the pathogenesis of lupus. Here, we report a rare case of a female patient diagnosed with mosaic Turner syndrome and subsequently presenting with juvenile-onset SLE. DNA methylation patterns were analyzed in this patient and compared with age-matched female SLE controls, revealing higher methylation levels in interferon-regulated genes previously shown to be hypomethylated in SLE. These data provide a potential link between a gene-dose effect from the X-chromosome and the lupus-defining epigenotype. We hypothesize that the attenuated demethylation in interferon-regulated genes might provide a protective effect explaining the rarity of SLE in Turner syndrome.

Current progress in CRISPR-Cas systems for autoimmune diseases

A body develops an autoimmune illness when its immune system mistakenly targets healthy cells and organs. Eight million people are affected by more than 80 autoimmune diseases. The public's and individuals' well-being is put at risk. Type 1 diabetes, lupus, rheumatoid arthritis, and multiple sclerosisare autoimmune diseases. Tissue injury, nociceptive responses, and persistent inflammation are the results of these stresses. Concerns about healthcare costs, health, and physical limitations contribute to these issues. Given their prevalence, it is crucial to enhance our knowledge, conduct thorough research, and provide all-encompassing support to women dealing with autoimmune diseases. This will lead to better public health and better patient outcomes. Most bacteria's immune systems employ CRISPR-Cas, a state-of-the-art technique for editing genes. For Cas to break DNA with pinpoint accuracy, a guide RNA employs a predetermined enzymatic pathway. Genetic modifications started. After it was developed, this method was subjected to much research on autoimmune diseases. By modifying immune pathways, CRISPR gene editing can alleviate symptoms, promote immune system tolerance, and decrease autoimmune reactivity. The autoimmune diseases that CRISPR-Cas9 targets now have no treatment or cure. Results from early clinical trials and preclinical studies of autoimmune medicines engineered using CRISPR showed promise. Modern treatments for rheumatoid arthritis,multiple sclerosis, and type 1 diabetes aim to alter specific genetic or immune mechanisms. Accurate CRISPR editing can fix autoimmune genetic disorders. Modifying effector cells with CRISPR can decrease autoimmune reactions. These cells include cytotoxic T and B lymphocytes. Because of improvements in delivery techniques and kits, CRISPR medications are now safer, more effective, and more accurately targeted. It all comes down to intricate immunological reactions and unexpected side consequences. Revolutionary cures for autoimmune problems and highly personalized medical therapies have been made possible by recent advancements in CRISPR.

A New Case of Paediatric Systemic Lupus Erythematosus with Onset after SARS-CoV-2 and Epstein-Barr Infection-A Case Report and Literature Review

Viral infections caused by exposure to viruses such as Epstein-Barr, cytomegalovirus, or Parvovirus B19 have always been considered predisposing environmental factors for the onset of autoimmune diseases. More recently, autoimmune mechanisms such as molecular mimicry, T-cell activation, transient immunosuppression and inflammation have also been observed in cases of SARS-CoV-2 infection. Several newly diagnosed autoimmune disorders have been reported post-COVID-19, such as COVID-19-associated multisystemic inflammatory syndrome in children (MIS-C), type 1 diabetes mellitus, systemic lupus erythematosus, or rheumatoid arthritis. In this article, we present a new case of paediatric systemic lupus erythematosus (SLE) with haematological (macrophage activation syndrome), renal (stage 2), cutaneous (urticarial vasculitis) and digestive involvement, onset three and a half months post-COVID-19. In the dynamics, de novo infection generated by Epstein-Barr exposure was associated. The diagnosis was confirmed based on EULAR/ACR 2019 criteria. The aim of the article is to present a possible correlation between SARS-CoV-2 and Epstein-Barr as extrinsic factors in triggering or activating paediatric systemic lupus erythematosus. Keywords: paediatric systemic lupus erythematosus; post-COVID-19; Epstein-Barr; SARS- CoV-2; case report; paediatric patient.

Increased Urine Excretion of Neutrophil Granule Cargo in Active Proliferative Lupus Nephritis

Key Points

Neutrophil degranulation participates in glomerular injury in proliferative lupus nephritis. Urine excretion of neutrophil granule proteins is a potential diagnostic for proliferative lupus nephritis.

Background

Lupus nephritis (LN) occurs in more than half of patients with systemic lupus erythematosus, but the cellular and molecular events that contribute to LN are not clearly defined. We reported previously that neutrophil degranulation participates in glomerular injury in mouse models of acute LN. This study tests the hypothesis that glomerular recruitment and subsequent activation of neutrophils result in urine excretion of neutrophil granule constituents that are predictive of glomerular inflammation in proliferative LN.

Methods

Urine and serum levels of 11 neutrophil granule proteins were measured by antibody-based array in patients with proliferative LN and healthy donors (HDs), and the results were confirmed by ELISA. Glomerular neutrophil accumulation was assessed in biopsies of patients with LN who contributed urine for granule cargo quantitation and normal kidney tissue by microscopy. Degranulation was measured by flow cytometry in neutrophils isolated from patients with LN and HD controls by cell surface granule markers CD63 (azurophilic), CC66b (specific), and CD35 (secretory). Nonparametric statistical analyses were performed and corrected for multiple comparisons.

Results

Eight granule proteins (myeloperoxidase, neutrophil elastase, azurocidin, olfactomedin-4, lactoferrin, alpha-1-acid glycoprotein 1, matrix metalloproteinase 9, and cathelicidin) were significantly elevated in urine from patients with active proliferative LN by array and/or ELISA, whereas only neutrophil elastase was increased in LN serum. Urine excretion of alpha-1-acid glycoprotein 1 declined in patients who achieved remission. The majority of LN glomeruli contained ≥3 neutrophils. Basal levels of specific granule markers were increased in neutrophils from patients with LN compared with HD controls. Serum from patients with active LN stimulated specific and secretory, but not azurophilic granule, release by HD neutrophils.

Conclusions

Circulating neutrophils in patients with LN are primed for enhanced degranulation. Glomerular recruitment of those primed neutrophils leads to release and urine excretion of neutrophil granule cargo that serves as a urine marker of active glomerular inflammation in proliferative LN.

Baricitinib in the treatment of systemic lupus erythematosus: a systematic review of randomized controlled trials

Background

Baricitinib, a Janus Kinase (JAK) inhibitor, has emerged as a potential therapeutic option for systemic lupus erythematosus (SLE). This systematic review aims to synthesize evidence from randomized controlled trials (RCTs) evaluating the potential of baricitinib in treating SLE.

Methods

A systematic search was conducted across electronic databases to identify relevant RCTs assessing baricitinib in patients with SLE. Studies reporting outcomes such as the Systemic Lupus Erythematosus Responder Index-4 (SRI-4), adverse events, and safety profiles were included. Data extraction and quality assessment were performed following PRISMA guidelines.

Results

A total of four studies were evaluated for efficacy and safety of baricitinib therapy. Three studies reported SRI-4, British Isles Lupus Assessment Group (BILAG), and Systemic Lupus Erythematosus Disease Activity Index-2000 (SLEDAI-2K), except for Dorner and colleagues Only Dorner and colleagues and Wallace and colleagues discuss the anti-dsDNA titres following treatment with baricitinib. The findings consistently demonstrated improved efficacy of baricitinib compared to placebo, particularly in terms of SRI-4 scores. Higher dosages of baricitinib showed significant improvement in disease activity and severity indices. Adverse events, including infections and gastrointestinal disturbances, were reported.

Conclusion

Baricitinib holds promise for treating SLE, but caution is needed due to potential adverse events. Careful patient selection and monitoring are crucial. Future research should prioritize long-term safety and comparative effectiveness studies to better understand baricitinib's role in managing SLE.

Mesenchymal stem cell transplantation may be able to induce immunological tolerance in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a common, potentially fatal autoimmune disease involving a significant inflammatory response. SLE is characterised by failure of self-tolerance and activation of autoreactive lymphocytes, leading to persistent disease. Although current treatments achieve some improvement in patients, some SLE patients are refractory and others relapse after drug withdrawal. The toxicity of current drug regimens, with recurrent infections, together with ongoing inflammation, contribute significantly to the progressive decline in organ function. Therefore, the clinical management of SLE requires more effective and less toxic treatments, ideally inducing complete remission and self-tolerance. In this context, recently developed cell therapies based on mesenchymal stem cells (MSCs) represent a promising and safe strategy in SLE. MSCs inhibit the activation of B cells, prevent the differentiation of CD4⁺ T cells into autoreactive T cells, reprogram macrophages with anti-inflammatory effects and inhibit dendritic cells (DCs), limiting their activity as antigen-presenting cells. In addition, MSCs could induce antigen-specific tolerance by enhancing anergy processes in autoreactive cells - by inhibiting the maturation of antigen-presenting DCs, blocking the T cell receptor (TcR) pathway and secreting inhibitory molecules -, increasing apoptotic activity to eliminate them, and activating regulatory T cells (Tregs) to enhance their proliferation and induction of tolerogenic DCs. Thus, induction of self-tolerance leads to immune balance, keeping inflammation under control and reducing lupus flares.

Belimumab in early systemic lupus erythematosus: A propensity score matching analysis

OBJECTIVE

This study aimed to evaluate the clinical efficacy of belimumab in patients with early systemic lupus erythematosus (SLE), defined as having a disease duration of less than 6 months.

METHODS

We retrospectively identified patients with SLE in the early stage who received belimumab and standard of care (belimumab group) or standard of care alone (control group) since September 2020. Propensity score matching (PSM) was used to reduce potential bias. The primary endpoint was lupus low disease activity status (LLDAS) at weeks 12 and 24. The secondary endpoints were remission and the proportion of glucocorticoid dose tapering to 7.5 mg/day. The efficacy of belimumab in patients with lupus nephritis was also assessed.

RESULTS

Out of 111 eligible patients, 16 patients in the belimumab group and 31 patients in the control group were identified by 1:2 PSM. At week 24, a significantly higher proportion of individuals achieved low disease activity state (LLDAS) in the belimumab group compared to the control group (56.3% vs. 19.4%, OR = 5.357, 95% CI = 1.417 to 20.260, p = 0.013). Furthermore, more patients in the belimumab group were reduced to low-dose glucocorticoid ( ≤ 7.5 mg/day) at week 24 (75.0% vs. 35.5%, OR = 5.182, 95%CI = 1.339 to 20.058, p = 0.017). Significant improvements in Patient Global Assessment scores were observed at Week 12 and 24 for those treated with belimumab compared to controls. In a subgroup analysis evaluating the efficacy of belimumab in patients with lupus nephritis, 42.9% of the seven individuals treated with belimumab achieved a complete renal response (CRR) by Week 24, and no instances of disease relapse were observed.

CONCLUSIONS

In SLE patients with a disease duration of less than 6 months, belimumab treatment can promote LLDAS achievement and reduce glucocorticoid dose, leading to a better prognosis. Introducing belimumab in the early stage of SLE may be a beneficial decision.

Glutaminolysis is a Potential Therapeutic Target for Kidney Diseases

Metabolic reprogramming contributes to the progression and prognosis of various kidney diseases. Glutamine is the most abundant free amino acid in the body and participates in more metabolic processes than other amino acids. Altered glutamine metabolism is a prominent feature in different kidney diseases. Glutaminolysis converts glutamine into the TCA cycle metabolite, alpha-ketoglutarate, via a cascade of enzymatic reactions. This metabolic pathway plays pivotal roles in inflammation, maladaptive repair, cell survival and proliferation, redox homeostasis, and immune regulation. Given the crucial role of glutaminolysis in bioenergetics and anaplerotic fluxes in kidney pathogenesis, studies on this cascade could provide a better understanding of kidney diseases, thus inspiring the development of potential methods for targeted therapy. Emerging evidence has shown that targeting glutaminolysis is a promising therapeutic strategy for ameliorating kidney disease. In this narrative review, equation including keywords related to glutamine, glutaminolysis and kidney are subjected to an exhaustive search on Pubmed database, we identified all relevant articles published before 1 April, 2024. Afterwards, we summarize the regulation of glutaminolysis in major kidney diseases and its underlying molecular mechanisms. Furthermore, we highlight therapeutic strategies targeting glutaminolysis and their potential clinical applications.

[Rare Autoimmune Diseases Role of Genetics - Example of Systemic Lupus Erythematosus]

Systemic lupus erythematosus (SLE) presents a complex clinical landscape with diverse manifestations, suggesting a multifactorial etiology. However, the identification of rare monogenic forms of the disease has shed light on specific genetic defects underlying SLE pathogenesis, offering valuable insights into its underlying mechanisms and clinical heterogeneity. By categorizing these monogenic forms based on the implicated signaling pathways, such as apoptotic body clearance, type I interferon signaling, JAK-STAT pathway dysregulation, innate immune receptor dysfunction and lymphocytic abnormalities, a more nuanced understanding of SLE's molecular basis emerges. Particularly in pediatric populations, where monogenic forms are more prevalent, routine genetic testing becomes increasingly important, with a diagnostic yield of approximately 10% depending on the demographic and methodological factors involved. This approach not only enhances diagnostic accuracy but also informs personalized treatment strategies tailored to the specific molecular defects driving the disease phenotype.

Global research trends in precision-targeted therapies for systemic lupus erythematosus (2003-2023): A bibliographic study

Background

Systemic lupus erythematosus (SLE) is a persistent inflammatory disease caused by an autoimmune response that predominantly affects multiple organs and systems. Growing evidence highlights the critical role of precision-targeted therapies in the management of SLE. Surprisingly, only a handful of bibliometric studies have thoroughly assessed this area. This study attempts to assess the global landscape of literature output and research trends related to precision-targeted therapy for SLE.

Method

Publications related to precision-targeted therapy for SLE from 2003 to 2023 were searched in the Web of Science Core Collection (WoSCC) database. VOSviewers, CiteSpace and the R package "bibliometrix" were used to perform this bibliometric analysis.

Results

A total of 3700 papers were retrieved, showing a steady annual increase in publications from 2003 to 2022. The United States led the field with the highest number of papers (36.1 %) and secured the top position in terms of citation frequency (59,889) and H-index (115). Anhui Medical University System claimed the top spot with an impressive output of 70 papers. Principal investigators Tsokos, George C. C., and Lu, Qianjin led the research effort. Among the journals, Frontiers in Immunology stood out, publishing the highest number of articles with 191. In particular, precision-targeted therapy for SLE has become a major research focus in recent years, covering aspects such as T cells, B cells, oxidative stress, remission, and PHASE-III.

Conclusion

This bibliometric study of ours systematically analyses research trends in precision targeted therapy for systemic lupus erythematosus, and this information identifies the research frontiers and hot directions in recent years and will serve as a reference for scientists working on targeted therapies.

Exploring the Role of PD-1 in the Autoimmune Response: Insights into Its Implication in Systemic Lupus Erythematosus

Despite advances in understanding systemic lupus erythematosus (SLE), many challenges remain in unraveling the precise mechanisms behind the disease's development and progression. Recent evidence has questioned the role of programmed cell death protein 1 (PD-1) in suppressing autoreactive CD4+ T cells during autoimmune responses. Research has investigated the potential impacts of PD-1 on various CD4+ T-cell subpopulations, including T follicular helper (Tfh) cells, circulating Tfh (cTfh) cells, and T peripheral helper (Tph) cells, all of which exhibit substantial PD-1 expression and are closely related to several autoimmune disorders, including SLE. This review highlights the complex role of PD-1 in autoimmunity and emphasizes the imperative for further research to elucidate its functions during autoreactive T-cell responses. Additionally, we address the potential of PD-1 and its ligands as possible therapeutic targets in SLE.

Understanding Autoimmunity: Mechanisms, Predisposing Factors, and Cytokine Therapies

Autoimmunity refers to an organism's immune response against its own healthy cells, tissues, or components, potentially leading to irreversible damage to vital organs. Central and peripheral tolerance mechanisms play crucial roles in preventing autoimmunity by eliminating self-reactive T and B cells. The disruption of immunological tolerance, characterized by the failure of these mechanisms, results in the aberrant activation of autoreactive lymphocytes that target self-tissues, culminating in the pathogenesis of autoimmune disorders. Genetic predispositions, environmental exposures, and immunoregulatory disturbances synergistically contribute to the susceptibility and initiation of autoimmune pathologies. Within the realm of immune therapies for autoimmune diseases, cytokine therapies have emerged as a specialized strategy, targeting cytokine-mediated regulatory pathways to rectify immunological imbalances. Proinflammatory cytokines are key players in inducing and propagating autoimmune inflammation, highlighting the potential of cytokine therapies in managing autoimmune conditions. This review discusses the etiology of autoimmune diseases, current therapeutic approaches, and prospects for future drug design.