Systemic lupus erythematosus

Obesity is associated with pain and impaired mobility despite therapy in systemic lupus erythematosus

Objective

To investigate whether abnormal BMI is associated with health-related quality of life (HRQoL) impairments, defined as patient-reported problems within the different dimensions of the three-level EQ-5D (EQ-5D-3L), before and after treatment for active systemic lupus erythematosus (SLE).

Patients and methods

We conducted a post-hoc analysis of data from two phase III clinical trials of belimumab in SLE, i.e., BLISS-52 (n = 865) and BLISS-76 (n = 819). Underweight was defined as BMI <18.5 kg/m2, normal weight as BMI ≥18.5 but <25 kg/m2, pre-obesity as BMI ≥25 but <30 kg/m2, and obesity as BMI ≥30 kg/m2. We investigated associations between BMI groups and problems (level 2 or 3) within each one of the five EQ-5D dimensions before treatment initiation and at week 52, using logistic regression analysis adjusting for age, ethnicity, disease activity, and glucocorticoid dose, and for the post-treatment analysis also for belimumab treatment and baseline EQ-5D-3L responses.

Results

Of 1,684 patients included, 73 (4%) were classified as underweight, 850 (50%) as normal weight, 438 (26%) as pre-obese, and 323 (19%) as obese. At baseline, obesity was associated with mild to severe problems in all EQ-5D dimensions (p < 0.05 for all), yielding the strongest association with problems in mobility (adjusted odds ratio, aOR: 2.1; 95% confidence interval, CI: 1.6-2.8; p < 0.001). Pre-obesity was also associated with problems in mobility (aOR: 1.4; 95% CI: 1.1-1.8; p = 0.005). Post-intervention, obesity was associated with problems in mobility and pain/discomfort, and pre-obesity with problems in mobility and self-care (p < 0.05 for all).

Conclusion

Our study adds to the evidence that high BMI negatively affects SLE patients' HRQoL, with obesity being associated with pain and impaired mobility despite therapy.

Iguratimod suppresses Tfh cell differentiation in primary Sjögren's syndrome patients through inhibiting Akt/mTOR/STAT3 signaling

BACKGROUND

Iguratimod (IGU) reduces hypergammaglobulinemia and disease activity in pSS (primary Sjögren's syndrome) patients. However, the therapeutical mechanism of IGU for pSS remains largely unknown. This study aimed to investigate the regulation of Tfh cell differentiation by IGU in pSS patients.

METHODS

We prospectively enrolled 13 pSS patients treated with IGU for 3 months and examined circulating T cell and B cell subsets by flow cytometry. We measured Tfh cell differentiation treated by IGU in pSS patients and healthy controls. Transcriptome analysis combined with molecular docking were employed to identify potential therapeutical targets of IGU, which were verified by Western blot and Tfh cell differentiation.

RESULTS

Tfh, plasmablast, and plasma cells were suppressed by IGU treatment at 1 and 3 months. Tfh cell differentiation and function were significant inhibited by IGU in pSS patients and healthy controls in vitro. Pyruvate dehydrogenase kinase 1 (PDK1) was identified as a target of IGU during Tfh cell differentiation, and the downstream Akt phosphorylation was attenuated by IGU. Moreover, the activity of mTORC1 and phosphorylation of STAT3 were suppressed by IGU, with downregulation of BCL6 and upregulation of PRDM1. Finally, Akt activator restored IGU-suppressed Tfh cell differentiation.

CONCLUSIONS

IGU suppresses Tfh cell differentiation in pSS patients through interacting with PDK1 and suppressing Akt-mTOR-STAT3 signaling.

B cell-intrinsic TLR7 expression drives severe lupus in TLR9-deficient mice

The endosomal Toll-like receptor 7 (TLR7) is a major driver of murine and human systemic lupus erythematosus (SLE). The role of TLR7 in lupus pathogenesis is enhanced when the regulatory role of TLR9 is absent. TLR7 signaling in plasmacytoid DCs (pDC) is generally thought to be a major driver of the IFN response and disease pathology; however, the cell types in which TLR7 acts to mediate disease have not been distinguished. To address this, we selectively deleted TLR7 in either CD11c+ cells or CD19+ cells; using a TLR7-floxed allele, we created on the lupus-prone MRL/lpr background, along with a BM chimera strategy. Unexpectedly, TLR7 deficiency in CD11c+ cells had no impact on disease, while TLR7 deficiency in CD19+ B cells yielded mild suppression of proteinuria and a trend toward reduced glomerular disease. However, in TLR9-deficient MRL/lpr mice with accelerated SLE, B cell-specific TLR7 deficiency greatly improved disease. These results support revision of the mechanism by which TLR7 drives lupus and highlight a cis regulatory interaction between the protective TLR9 and the pathogenic TLR7 within the B cell compartment. They suggest B cell-directed, dual TLR7 antagonism/TLR9 agonism or dual TLR7/9 antagonism as a potential future therapeutic strategy to treat SLE.

BAFF system expression in double negative 2, activated naïve and activated memory B cells in systemic lupus erythematosus

Introduction

B cell activating factor (BAFF) has an important role in normal B cell development. The aberrant expression of BAFF is related with the autoimmune diseases development like Systemic Lupus Erythematosus (SLE) for promoting self-reactive B cells survival. BAFF functions are exerted through its receptors BAFF-R (BR3), transmembrane activator calcium modulator and cyclophilin ligand interactor (TACI) and B cell maturation antigen (BCMA) that are reported to have differential expression on B cells in SLE. Recently, atypical B cells that express CD11c have been associated with SLE because they are prone to develop into antibody-secreting cells, however the relationship with BAFF remains unclear. This study aims to analyze the BAFF system expression on CXCR5- CD11c+ atypical B cell subsets double negative 2 (DN2), activated naïve (aNAV), switched memory (SWM) and unswitched memory (USM) B cells.

Methods

Forty-five SLE patients and 15 healthy subjects (HS) were included. Flow cytometry was used to evaluate the expression of the receptors in the B cell subpopulations. Enzyme-linked immunosorbent assay (ELISA) was performed to quantify the soluble levels of BAFF (sBAFF) and IL-21.

Results

We found increased frequency of CXCR5- CD11c+ atypical B cell subpopulations DN2, aNAV, SWM and USM B cells in SLE patients compared to HS. SLE patients had increased expression of membrane BAFF (mBAFF) and BCMA receptor in classic B cell subsets (DN, NAV, SWM and USM). Also, the CXCR5+ CD11c- DN1, resting naïve (rNAV), SWM and USM B cell subsets showed higher mBAFF expression in SLE. CXCR5- CD11c+ atypical B cell subpopulations DN2, SWM and USM B cells showed strong correlations with the expression of BAFF receptors. The atypical B cells DN2 in SLE showed significant decreased expression of TACI, which correlated with higher IL-21 levels. Also, lower expression of TACI in atypical B cell DN2 was associated with high disease activity.

Discussion

These results suggest a participation of the BAFF system in CXCR5- CD11c+ atypical B cell subsets in SLE patients. Decreased TACI expression on atypical B cells DN2 correlated with high disease activity in SLE patients supporting the immunoregulatory role of TACI in autoimmunity.

Quantitative analysis of JAK/STAT signaling pathway in patients of inflammatory skin disorders

BACKGROUND

Inflammatory skin diseases (ISDs), are characterized by dysregulated activation of innate and adaptive immune systems, with inflammatory cytokines playing a crucial role in their pathogenesis.

OBJECTIVES

This study aimed to investigate the involvement of Janus kinase/signal transduction and activator of transcription (JAK/STAT) signaling pathway in the pathogenesis of ISDs.

METHODS

The study analyzed a total of 117 skin biopsies, comprising 31 from pyoderma gangrenosum (PG), 25 from hidradenitis suppurativa (HS), 35 from psoriasis patients, and 26 from control subjects. To assess the expression levels of JAK/STAT pathway components, immunohistochemical staining was performed on both the dermal and epidermal layers of the skin. The Histo score (H score) was utilized as the immunoexpression score to evaluate the staining intensity.

RESULTS

The results indicated that all components of the JAK/STAT signaling pathway, except JAK2 and STAT6 in PG, JAK1, STAT4, and STAT6 in HS, and JAK1 in psoriasis, were overexpressed in the dermal skin compared to the control group (p < 0.05). Psoriatic skin had higher expression of STAT6 than both PG and HS and higher expression of JAK2 than PG (p < 0.05). Additionally, HS biopsies had higher expression of JAK2 and STAT6 compared to PG (p < 0.05). JAK1 expression was higher in PG than in HS, psoriasis, and the control group (mean H score was 265.8, 184.8, 191.4, and 113.1, p < 0.05, respectively).

CONCLUSIONS

This study provides new insights into the potential contribution of the JAK/STAT pathway to the pathogenesis of ISDs. The findings suggest that targeting this pathway could be a promising therapeutic strategy for treating these disorders.

Daratumumab monotherapy for refractory lupus nephritis

Treatment-refractory lupus nephritis (LN) has a high risk of a poor outcome and is often life-threatening. Here we report a case series of six patients (one male and five females) with a median age of 41.3 years (range, 20-61 years) with refractory LN who received renal biopsies and were subsequently treated with intravenous daratumumab, an anti-CD38 monoclonal antibody (weekly for 8 weeks, followed by eight biweekly infusions and up to eight monthly infusions). One patient did not show any improvement after 6 months of therapy, and daratumumab was discontinued. In five patients, the mean disease activity, as assessed by the Systemic Lupus Erythematosus Disease Activity 2000 index, decreased from 10.8 before treatment to 3.6 at 12 months after treatment. Mean proteinuria (5.6 g per 24 h to 0.8 g per 24 h) and mean serum creatinine (2.3 mg dl-1 to 1.5 mg dl-1) also decreased after 12 months. Improvement of clinical symptoms was accompanied by seroconversion of anti-double-stranded DNA antibodies; decreases in median interferon-gamma levels, B cell maturation antigen and soluble CD163 levels; and increases in C4 and interleukin-10 levels. These data suggest that daratumumab monotherapy warrants further exploration as a potential treatment for refractory LN.

Viewpoint on anifrolumab in patients with systemic lupus erythematosus and a high unmet need in clinical practice

Systemic lupus erythematosus (SLE) is a heterogeneous autoimmune disease characterised by unpredictable flares. Many patients with SLE are unable to achieve the recommended treatment goal of remission or the intermediate, yet still clinically beneficial, goal of Lupus Low Disease Activity State (LLDAS) with standard of care (SoC) treatments. LLDAS is an emerging treat-to-target goal in SLE with the aim of reducing organ damage and mortality. A high unmet need remains in SLE and mainstay glucocorticoid treatment is associated with unacceptable toxicity. The recently approved type I interferon receptor antagonist anifrolumab is a new treatment option for this historically underserved patient population. In phase 3 trials, a higher percentage of patients on anifrolumab achieved remission, as defined by the Definition Of Remission In SLE (DORIS), and LLDAS compared with placebo. Real-world clinical experience with anifrolumab use is still limited. Until real-world study results and updated treatment guidelines are available, personal expert clinical experience supported by data may inform clinical decision-making. This viewpoint article discusses four example patient types that could be considered for anifrolumab treatment based on (1) high-risk features early in the disease course, (2) inability to achieve and (3) maintain at least LLDAS, or (4) a desire to reduce or stop SoC. These patients with high unmet need may benefit from the addition of anifrolumab to SoC to achieve or maintain the therapeutic goals of LLDAS or DORIS remission.

Epidemiology and Damage Accrual of Systemic Lupus Erythematosus in Central Sweden: A Single-Center Population-Based Cohort Study Over 14 Years From Östergötland County

OBJECTIVE

Variations in prevalence and incidence of systemic lupus erythematosus (SLE) within a geographically defined area of central Sweden over a time period of 14 years were examined. Longitudinal differences in disease activity, laboratory test results, and damage accrual were investigated.

METHODS

Adults (aged ≥18 years) residing in Östergötland County between 2008 and 2021 (mean adult population: 357,000 citizens) with confirmed SLE were identified and followed prospectively until death, December 31, 2021, or emigration. We estimated annual incidence per 100,000 inhabitants stratified by sex and age. Linear regression with year of diagnosis as the outcome assessed whether each clinical measurement at diagnosis varied over time.

RESULTS

Prevalence on December 31, 2021, was 71.5 of 100,000 (87% female). One hundred twenty-six new cases were identified during the study period, yielding a mean annual incidence of 3.0 of 100,000 inhabitants; this was higher in females (4.8/100,000) than in males (1.2/100,000). Mean age at diagnosis was 43.7 years (SD 17.3). Age at diagnosis and disease activity measures increased over the calendar year of diagnosis (P < 0.05) whereas disease manifestations, including lupus nephritis, did not vary significantly. Accrual of organ damage was demonstrated over time since diagnosis and stratified by sex, lupus nephritis, and corticosteroid-related damage. Approximately 40% developed damage within 5 years.

CONCLUSION

SLE prevalence and incidence estimates remained constant over 14 years, and disease phenotypes at SLE onset were similar. SLE was diagnosed also among older individuals with a smaller female-to-male ratio. Estimates of prevalence and incidence were comparable to previous Scandinavian reports but lower than observed in registry data from the US and the UK.

Systematic literature review informing the EULAR recommendations for the non-pharmacological management of systemic lupus erythematosus and systemic sclerosis

Through this systematic literature review, we assembled evidence to inform the EULAR recommendations for the non-pharmacological management of systemic lupus erythematosus (SLE) and systemic sclerosis (SSc). We screened articles published between January 2000 and June 2021. Studies selected for data extraction (118 for SLE and 92 for SSc) were thematically categorised by the character of their intervention. Of 208 articles included, 51 were classified as robust in critical appraisal. Physical activity was the most studied management strategy and was found to be efficacious in both diseases. Patient education and self-management also constituted widely studied topics. Many studies on SLE found psychological interventions to improve quality of life. Studies on SSc found phototherapy and laser treatment to improve cutaneous disease manifestations. In summary, non-pharmacological management of SLE and SSc encompasses a wide range of interventions, which can be combined and provided either with or without adjunct pharmacological treatment but should not aim to substitute the latter when this is deemed required. While some management strategies i.e., physical exercise and patient education, are already established in current clinical practice in several centres, others e.g., phototherapy and laser treatment, show both feasibility and efficacy, yet require testing in more rigorous trials than those hitherto conducted.

Pathogenesis of systemic lupus erythematosus: risks, mechanisms and therapeutic targets

Research elucidating the pathogenesis of systemic lupus erythematosus (SLE) has defined two critical families of mediators, type I interferon (IFN-I) and autoantibodies targeting nucleic acids and nucleic acid-binding proteins, as fundamental contributors to the disease. On the fertile background of significant genetic risk, a triggering stimulus, perhaps microbial, induces IFN-I, autoantibody production or most likely both. When innate and adaptive immune system cells are engaged and collaborate in the autoimmune response, clinical SLE can develop. This review describes recent data from genetic analyses of patients with SLE, along with current studies of innate and adaptive immune function that contribute to sustained IFN-I pathway activation, immune activation and autoantibody production, generation of inflammatory mediators and tissue damage. The goal of these studies is to understand disease mechanisms, identify therapeutic targets and stimulate development of therapeutics that can achieve improved outcomes for patients.

Screening of Potential Circulating Diagnostic Biomarkers and Molecular Mechanisms of Systemic Lupus Erythematosus-Related Myocardial Infarction by Integrative Analysis

Background

The risk of acute myocardial infarction (AMI) is elevated in patients with systemic lupus erythematosus (SLE), and it is of great clinical value to identify potential molecular mechanisms and diagnostic markers of AMI associated with SLE by analyzing public database data and transcriptome sequencing data.

Methods

AMI and SLE-related sequencing datasets GSE62646, GSE60993, GSE50772 and GSE81622 were downloaded from the Gene Expression Omnibus (GEO) database and divided into prediction and validation cohorts. To identify the key genes associated with AMI related to SLE, WGCNA and DEGs analysis were performed for the prediction and validation cohorts, respectively. The related signaling pathways were identified by GO/KEGG enrichment analysis. Peripheral blood mononuclear cells (PBMCs) from patients with AMI were collected for transcriptome sequencing to validate the expression of key genes in patients with AMI. Least absolute shrinkage and selection operator (LASSO) regression analysis was applied to screen diagnostic biomarkers. The diagnostic efficacy of biomarkers was validated by ROC analysis, and the CIBERSORTx platform was used to analyze the composition of immune cells in AMI and SLE.

Results

A total of 108 genes closely related to AMI and SLE were identified in the prediction cohort, and GO/KEGG analysis showed significantly enriched signaling pathways. The results of differential analysis in validation cohort were consistent with them. By transcriptional sequencing of PBMCs from peripheral blood of AMI patients, combined with the results of prediction and validation cohort analysis, seven genes were finally screened out. LASSO analysis finally identifies DYSF, LRG1 and CSF3R as diagnostic biomarkers of SLE-related-AMI. CIBERSORTx analysis revealed that the biomarkers were highly correlated with neutrophils.

Conclusion

Neutrophil degranulation and NETs formation play important roles in SLE-related AMI, and DYSF, LRG1 and CSF3R were identified as important diagnostic markers for the development and progression of SLE-related AMI.

CAR-T State of the Art and Future Challenges, A Regulatory Perspective

This review is an outlook on CAR-T development up to the beginning of 2023, with a special focus on the European landscape and its regulatory field, highlighting the main features and limitations affecting this innovative therapy in cancer treatment. We analysed the current state of the art in the EU and set out a showcase of the field's potential advancements in the coming years. For this analysis, the data used came from the available scientific literature as well as from the European Medicines Agency and from clinical trial databases. The latter were investigated to query the studies on CAR-Ts that are active and/or relevant to the review process. As of this writing, CAR-Ts have started to move past the "ceiling" of third-line treatment with positive results in comparison trials with the Standard of Care (SoC). One such example is the trial Zuma-7 (NCT03391466), which resulted in approval of CAR-T products (Yescarta™) for second-line treatment, a crucial achievement for the field which can increase the use of this type of therapy. Despite exciting results in clinical trials, limitations are still many: they regard access, production, duration of response, resistance, safety, overall efficacy, and cost mitigation strategies. Nonetheless, CAR-T constructs are becoming more diverse, and the technology is starting to produce some remarkable results in treating diseases other than cancer.

Gut microbiota: a newly identified environmental factor in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that predominantly affects women of childbearing age and is characterized by the damage to multiple target organs. The pathogenesis of SLE is complex, and its etiology mainly involves genetic and environmental factors. At present, there is still a lack of effective means to cure SLE. In recent years, growing evidence has shown that gut microbiota, as an environmental factor, triggers autoimmunity through potential mechanisms including translocation and molecular mimicry, leads to immune dysregulation, and contributes to the development of SLE. Dietary intervention, drug therapy, probiotics supplement, fecal microbiome transplantation and other ways to modulate gut microbiota appear to be a potential treatment for SLE. In this review, the dysbiosis of gut microbiota in SLE, potential mechanisms linking gut microbiota and SLE, and immune dysregulation associated with gut microbiota in SLE are summarized.

[Systemic lupus erythematosus and antiphospholipid syndrome: past, present, future]

Immune-inflammatory (autoimmune and autoinflammatory) rheumatic diseases are widespread severe chronic inflammatory diseases and also "models" for studying the fundamental mechanisms of pathogenesis and approach to pharmacotherapy of other diseases associated with autoimmunity and/or autoinflammation. Uncontrolled inflammation leading to hypercoagulation forms the basis of "thromboinflammation", which is considered a universal pathogenetic mechanism of organ involvement in immune-inflammatory rheumatic diseases, as well as in COVID-19 and atherosclerotic vascular lesions (atherothrombosis). Thrombo-inflammatory mechanisms play a crucial role in systemic lupus erythematosus and antiphospholipid syndrome. Russian rheumatology, under the leadership of academician Valentina Alexandrovna Nasonova, greatly contributed to the research of these disorders. This article addresses the current view about the overlapping pathogenetic mechanisms of thrombosis in systemic lupus erythematosus and antiphospholipid syndrome, the relevance of these studies during the COVID-19 pandemic, and the prospects for antithrombotic and anti-inflammatory therapy.

Role of the SLIT-ROBO signaling pathway in renal pathophysiology and various renal diseases

SLIT ligand and its receptor ROBO were initially recognized for their role in axon guidance in central nervous system development. In recent years, as research has advanced, the role of the SLIT-ROBO signaling pathway has gradually expanded from axonal repulsion to cell migration, tumor development, angiogenesis, and bone metabolism. As a secreted protein, SLIT regulates various pathophysiological processes in the kidney, such as proinflammatory responses and fibrosis progression. Many studies have shown that SLIT-ROBO is extensively involved in various aspects of kidney development and maintenance of structure and function. The SLIT-ROBO signaling pathway also plays an important role in different types of kidney disease. This article reviews the advances in the study of the SLIT-ROBO pathway in various renal pathophysiological and kidney disorders and proposes new directions for further research in this field.

Centrally acting ACE inhibitor (cACEi) and angiotensin receptor blocker (cARB) use and cognitive dysfunction in patients with SLE

OBJECTIVE

Cognitive dysfunction (CD) is detectable in approximately 40% of patients with SLE. Despite this high prevalence, there are no approved pharmacological treatment options for this detrimental condition. Preliminary murine studies show potential for targeting microglial activation as a treatment of SLE-CD, which may be ameliorated with centrally acting ACE inhibitor (cACEi) and angiotensin receptor blocker (cARB) use. The aim of this study is to determine if there is an association of cACEi/cARB use with cognitive function in a human SLE cohort.

METHODS

The American College of Rheumatology neuropsychological battery was administered to patients with consecutive SLE at a single academic health centre at baseline, 6 and 12 months. Scores were compared with sex-matched and age-matched control subjects. Clinical and demographic data were gathered at each visit. The primary outcome was CD defined as dysfunction in two or more cognitive domains. The primary predictor was a total cumulative dose of cACEi/cARB in milligrams per kilogram, recorded as an equivalent ramipril dose. Odds of CD with respect to cACEi/cARB use were determined through generalised linear mixed modelling.

RESULTS

A total of 300 patients, representing 676 visits, completed this study. One hundred sixteen (39%) met the criteria for CD. Fifty-three participants (18%) were treated with a cACEi or cARB. Mean cumulative dose was 236 mg/kg (calculated as equivalent ramipril dose). Cumulative cACEi/cARB dose was not protective against SLE-CD. Caucasian ethnicity, current employment status and azathioprine cumulative dose were each associated with reduced odds of SLE-CD. Increasing Fatigue Severity Scale score was associated with increased odds of CD.

CONCLUSIONS

In a single-centre SLE cohort, cACEi/cARB use was not associated with absence of CD. Many important confounders may have influenced the results of this retrospective study. A randomised trial is required to accurately determine if cACEi/cARB is a potential treatment for SLE-CD.

Glomerulonephritis: immunopathogenesis and immunotherapy

'Glomerulonephritis' (GN) is a term used to describe a group of heterogeneous immune-mediated disorders characterized by inflammation of the filtration units of the kidney (the glomeruli). These disorders are currently classified largely on the basis of histopathological lesion patterns, but these patterns do not align well with their diverse pathological mechanisms and hence do not inform optimal therapy. Instead, we propose grouping GN disorders into five categories according to their immunopathogenesis: infection-related GN, autoimmune GN, alloimmune GN, autoinflammatory GN and monoclonal gammopathy-related GN. This categorization can inform the appropriate treatment; for example, infection control for infection-related GN, suppression of adaptive immunity for autoimmune GN and alloimmune GN, inhibition of single cytokines or complement factors for autoinflammatory GN arising from inborn errors in innate immunity, and plasma cell clone-directed or B cell clone-directed therapy for monoclonal gammopathies. Here we present the immunopathogenesis of GN and immunotherapies in use and in development and discuss how an immunopathogenesis-based GN classification can focus research, and improve patient management and teaching.

Impaired regulatory function of granzyme B-producing B cells against T cell inflammatory responses in lupus mice

OBJECTIVE

Recently, a new subtype of granzyme B (GrB)-producing Breg cells has been identified, which was proven to be involved in autoimmune disease. Our recent report demonstrated that GrB-producing Breg cells were correlated with clinical and immunological features of SLE. However, the effect of GrB-producing Breg cells in lupus mice is unclear.

METHODS

GrB expression in naïve and lupus mouse B cells was analysed using flow cytometry, PCR, ELISA and ELISpot assays. To study the role of GrB-producing B cells in a lupus model, GrB knockout (KO) and wild-type (WT) mice were intraperitoneally injected with monoclonal cells from the mutant mouse strain B6.C-H-2bm12 (bm12) for 2 weeks. In addition, the function of GrB-producing Breg cells in naïve and lupus mice was further explored using in vitro B cells-CD4⁺CD25^- T cell co-culture assays with GrB blockade/KO of B cells.

RESULTS

B cells from the spleens of WT C57BL/6 (B6) mice could express and secret GrB (p<0.001). GrB-producing Breg cells from WT mice showed their regulatory functions on CD4⁺CD25^- T cell. While the frequency of GrB-producing Breg cells was significantly decreased (p=0.001) in lupus mice (p<0.001). Moreover, GrB-producing Breg cells in lupus mice failed to suppress T cell-mediated proinflammatory responses, partially due to the impaired capacity of downregulating the T cell receptor-zeta chain and inducing CD4⁺CD25^- T cell apoptosis.

CONCLUSION

This study further revealed the function and mechanism of GrB-producing Breg cells in regulating T cell homeostasis in lupus mice and highlighted GrB-producing Breg cells as a therapeutic target in SLE.

Nanomaterials for antigen-specific immune tolerance therapy

Impairment of immune tolerance might cause autologous tissue damage or overactive immune response against non-pathogenic molecules. Although autoimmune disease and allergy have complicated pathologies, the current strategies have mainly focused on symptom amelioration or systemic immunosuppression which can lead to fatal adverse events. The induction of antigen-specific immune tolerance may provide therapeutic benefits to autoimmune disease and allergic response, while reducing nonspecific immune adverse responses. Diverse nanomaterials have been studied to induce antigen-specific immune tolerance therapy. This review will cover the immunological background of antigen-specific tolerance, clinical importance of antigen-specific immune tolerance, and nanomaterials designed for autoimmune and allergic diseases. As nanomaterials for modulating immune tolerances, lipid-based nanoparticles, polymeric nanoparticles, and biological carriers have been covered. Strategies to provide antigen-specific immune tolerance have been addressed. Finally, current challenges and perspectives of nanomaterials for antigen-specific immune tolerance therapy will be discussed.

Knowledge and Awareness of Systemic Lupus Erythematosus Among the Population of Makkah, Saudi Arabia: A Cross-Sectional Study

Background Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease that affects mostly females of childbearing age. The exact cause is still unknown, but hormonal and immunological features and genetic predisposition are considered likely etiological factors. Disease presentation is variable but is usually characterized by phases of remission and relapse. Objective This study was conducted to assess the knowledge and awareness of SLE among the general population of Makkah, Saudi Arabia. Methods Data were collected using an online survey created with Google Forms that was distributed to the residents of Makkah aged 18 years and older. The survey was disseminated between November 2022 and January 2023. Results A total of 488 participants were included in the study, and the mean age of the participants was 29.1 years; the majority were female (54%). Only 18.6% of the participants knew someone with SLE, while 52.3% had heard about SLE. Additionally, 79.9% of participants had below-average awareness of SLE. Moreover, 72.1% believed that awareness of SLE should be promoted; 65.5% knew about SLE from the Internet or e-resources. Finally, only 5.5% of the participants had heard about SLE from physicians. Conclusion This study showed an insufficient level of knowledge and awareness of SLE in the general population of Makkah. We recommend conducting physical and virtual disease awareness campaigns and activities to enhance the knowledge and awareness of SLE among the general population of Makkah and other parts of Saudi Arabia.

Brensocatib, an oral, reversible inhibitor of dipeptidyl peptidase 1, mitigates interferon-α-accelerated lupus nephritis in mice

Neutrophils have been implicated in initiating and perpetuating systemic lupus erythematosus and the resultant kidney damage in lupus nephritis (LN) patients, in part through an excessive release of neutrophil serine proteases (NSPs). NSP zymogens are activated by dipeptidyl peptidase 1 (DPP1) during neutrophil maturation and released by mature neutrophils in response to inflammatory stimuli. Thus, a potential strategy to attenuate disease progression in LN would be to inhibit DPP1. We tested whether brensocatib, a highly selective and reversible DPP1 inhibitor, could mitigate LN progression in an interferon-alpha (IFNα)-accelerated NZB/W F1 mouse model. To confirm brensocatib's pharmacodynamic effect on NSPs in this mouse strain, repeated dose studies were conducted for 7 and 14 days in naïve NZB/W F1 mice via oral gavage twice a day. Brensocatib at 2 and 20 mg/kg/day achieved a significant reduction in bone marrow NSP activities after 7 days of daily administration. To initiate LN disease progression, the mice were injected with an IFNα-expressing adenovirus. After 2 weeks, three brensocatib doses (or vehicle) were administered for 6 more weeks. Throughout the 8-week study, brensocatib treatment (20 mg/kg/day) significantly reduced the occurrence of severe proteinuria compared to the vehicle control. Brensocatib treatment also entailed a significant reduction in the urine albumin-to-creatinine ratio, indicating decreased kidney damage, as well as a significant reduction in blood urea nitrogen level, suggesting improved renal function. Based on kidney histopathology analysis, brensocatib treatment significantly lowered both the renal tubular protein score and the nephropathy score compared to the vehicle group. A trend towards reduced glomerulonephritis score with brensocatib treatment was also observed. Lastly, brensocatib significantly reduced LN mouse kidney infiltration by various inflammatory cells. In conclusion, these results suggest that brensocatib alters disease progression in LN mice and warrant further evaluation of DPP1 inhibition in LN.

Risk and Factors associated with disease manifestations in systemic lupus erythematosus - lupus nephritis (RIFLE-LN): a ten-year risk prediction strategy derived from a cohort of 1652 patients

Objectives

Lupus nephritis (LN) remains one of the most severe manifestations in patients with systemic lupus erythematosus (SLE). Onset and overall LN risk among SLE patients remains considerably difficult to predict. Utilizing a territory-wide longitudinal cohort of over 10 years serial follow-up data, we developed and validated a risk stratification strategy to predict LN risk among Chinese SLE patients - Risk and Factors associated with disease manifestations in systemic Lupus Erythematosus - Lupus Nephritis (RIFLE-LN).

Methods

Demographic and longitudinal data including autoantibody profiles, clinical manifestations, major organ involvement, LN biopsy results and outcomes were documented. Association analysis was performed to identify factors associated with LN. Regression modelling was used to develop a prediction model for 10-year risk of LN and thereafter validated.

Results

A total of 1652 patients were recruited: 1382 patients were assigned for training and validation of the RIFLE-LN model; while 270 were assigned for testing. The median follow-up duration was 21 years. In the training and validation cohort, 845 (61%) of SLE patients developed LN. Cox regression and log rank test showed significant positive association between male sex, age of SLE onset and anti-dsDNA positivity. These factors were thereafter used to develop RIFLE-LN. The algorithm was tested in 270 independent patients and showed good performance (AUC = 0·70).

Conclusion

By using male sex, anti-dsDNA positivity, age of SLE onset and SLE duration; RIFLE-LN can predict LN among Chinese SLE patients with good performance. We advocate its potential utility in guiding clinical management and disease monitoring. Further validation studies in independent cohorts are required.

Improvement of Pain Symptoms in Musculoskeletal Diseases After Multimodal Spa Therapy in the Austrian Gastein Valley-A Study Based on Longitudinal Registry Data

Objective: The study aim was to investigate the course of pain in rest and motion in seven different rheumatic diseases (RMD), prior and after multimodal spa therapy including low-dose radon treatment and at 3-, 6-; and 9-month follow up. Methods: Complete data from the radon indication registry including information on 561 subjects with RMD were analysed to explore the association of timepoint of measurement with pain in rest and motion. For this purpose, linear regression models adjusted for RMD-type, age, sex and body mass index (BMI) were applied. Results: The mean age of the sample was 55 years, the average body mass index was 26.8, and 275 subjects were women. Pain scores were significantly improved at all-time points compared to baseline. Pain courses were different for each RMD with the largest improvement seen in fibromyalgia. Conclusion: Timing spa facility visits according to RMD-specific pain courses may result in sustained pain reduction.

Plumbing mysterious RNAs in "dark genome" for the conquest of human diseases

Next-generation sequencing has revealed that less than 2% of transcribed genes are translated into proteins, with a large portion transcribed into noncoding RNAs (ncRNAs). Among these, long noncoding RNAs (lncRNAs) represent the largest group and are pervasively transcribed throughout the genome. Dysfunctions in lncRNAs have been found in various diseases, highlighting their potential as therapeutic, diagnostic, and prognostic targets. However, challenges, such as unknown molecular mechanisms and nonspecific immune responses, and issues of drug specificity and delivery present obstacles in translating lncRNAs into clinical applications. In this review, we summarize recent publications that have explored lncRNA functions in human diseases. We also discuss challenges and future directions for developing lncRNA treatments, aiming to bridge the gap between functional studies and clinical potential and inspire further exploration in the field.

T-cell immunoglobulin and mucin-domain containing-3 (TIM-3): Solving a key puzzle in autoimmune diseases

Dysfunctional immune cells participate in the pathogenesis of a variety of autoimmune diseases, although the specific mechanisms remain elusive and effective clinical interventions are lacking. Recent research on immune checkpoint molecules has revealed significant expression of T cell immunoglobulin and mucin domain-containing protein 3 (TIM-3) on the surfaces of various immune cells. These include different subsets of T cells, macrophages, dendritic cells, natural killer cells, and mast cells. Further investigation into its protein structure, ligands, and intracellular signaling pathway activation mechanisms has found that TIM-3, by binding with different ligands, is involved in the regulation of crucial biological processes such as proliferation, apoptosis, phenotypic transformation, effector protein synthesis, and cellular interactions of various immune cells. The TIM-3-ligand axis plays a pivotal role in the pathogenesis of numerous conditions, including autoimmune diseases, infections, cancers, transplant rejection, and chronic inflammation. This article primarily focuses on the research findings of TIM-3 in the field of autoimmune diseases, with a special emphasis on the structure and signaling pathways of TIM-3, its types of ligands, and the potential mechanisms implicated in systemic lupus erythematosus, multiple sclerosis, rheumatoid arthritis, as well as other autoimmune diseases and chronic inflammation. The latest research results in the field of immunology suggest that TIM-3 dysfunction affects various immune cells and participates in the pathogenesis of diseases. Monitoring the activity of its receptor-ligand axis can serve as a novel biological marker for disease clinical diagnosis and prognosis evaluation. More importantly, the TIM-3-ligand axis and the downstream signaling pathway molecules may become key targets for targeted intervention treatment of autoimmune-related diseases.

Targeted nanotherapy for kidney diseases: a comprehensive review

Kidney diseases represent a major public health problem, affecting millions of people worldwide. Moreover, the treatment of kidney diseases is burdened by the problematic effects of conventional drug delivery, such as systemic drug toxicity, rapid drug clearance, and the absence of precise targeting of the kidney. Although the use of nanotechnology in medicine is in its early stage and lacks robust translational studies, nanomedicines have already shown great promise as novel drug-delivery systems for the treatment of kidney disease. On the basis of our current knowledge of renal anatomy and physiology, pathophysiology of kidney diseases, and physicochemical characteristics of nanoparticles, an expansive repertoire and wide use of nanomedicines could be developed for kidney diseases in the near future. Some limitations have slowed the transition of these agents from preclinical studies to clinical trials, however. In this review, we summarize the current knowledge on renal drug-delivery systems and recent advances in renal cell targeting; we also demonstrate their important potential as future paradigm-shifting therapies for kidney diseases.

Myocarditis and Autoimmunity

INTRODUCTION

Autoimmune myocarditis may develop due to heterogeneous causes. Myocarditis is often caused by viral infections, but it can also be caused by systemic autoimmune diseases. Immune checkpoint inhibitors and virus vaccines induce immune activation, and they can cause the development of myocarditis, as well as several immune-related adverse events. The development of myocarditis is dependent on the genetic factors of the host, and the major histocompatibility complex (MHC) may be an important determinant of the type and severity of the disease. However, non-MHC immunoregulatory genes may also play a role in determining susceptibility.

AREA COVERED

This review summarizes the current knowledge of the etiology, pathogenesis, diagnosis and treatment of autoimmune myocarditis with a particular focus on viral infection and autoimmunity, and biomarkers of myocarditis.

EXPERT OPINION

An endomyocardial biopsy may not be the gold standard for the diagnosis of myocarditis. Cardiac magnetic resonance imaging is useful in diagnosing autoimmune myocarditis. Recently identified biomarkers of inflammation and myocyte injury are promising for the diagnosis of myocarditis when measured simultaneously. Future treatments should focus on the appropriate diagnosis of the etiologic agent, as well as on the specific stage of the evolution of immune and inflammatory processes.

Disentangling the Pathogenesis of Systemic Lupus Erythematosus: Close Ties between Immunological, Genetic and Environmental Factors

Systemic Lupus Erythematosus (SLE) is a systemic autoimmune disease that attacks various organ systems with a variety of clinical implications, ranging from mild skin and mucosal manifestations to severe central nervous system manifestations and death. Cases of SLE have been documented nearly two centuries ago when scholars used the terms 'erythema centrifugum' and 'seborrhea congestiva' to describe the discoid skin lesions and the butterfly or malar rash in SLE. Since then, knowledge about this disease has developed rapidly, especially knowledge related to the underlying pathogenesis of SLE. To date, it is known that immune system dysregulation, supported by genetic and environmental predisposition, can trigger the occurrence of SLE in a group of susceptible individuals. Various inflammatory mediators, cytokines and chemokines, as well as intra- and intercellular signaling pathways, are involved in the pathogenesis of SLE. In this review, we will discuss the molecular and cellular aspects of SLE pathogenesis, with a focus on how the immune system, genetics and the environment interact and trigger the various clinical manifestations of SLE.

Evaluation and correlation analysis of ocular surface disorders and quality of life in autoimmune rheumatic diseases: a cross-sectional study

OBJECTIVE

This cross-sectional study aimed to reveal the association between ocular surface disorders and psychological, physiological situations among autoimmune rheumatic patients.

METHODS

Ninety autoimmune rheumatic patients (180 eyes) hospitalized in the Department of Rheumatology, The Second Xiangya Hospital, Central South University and 30 controls (60 eyes) were enrolled in the study. All participants were assessed for ocular surface disorders including dry eye disease (DED) by the Ocular Surface Disease Index (OSDI) for symptoms evaluation, and slim lamp examinations for tear break-up time (TBUT), meibomian gland secretion, symblepharon and corneal clarity, Schirmer I test, corneal fluorescein staining (CFS), lid-parallel conjunctival folds (LIPCOF). Systematic conditions were evaluated using the Short Form 36-Health Survey (SF-36) for health-related quality of life, Hospital Anxiety and Depression Scale (HADS) for anxiety and depression, Health Assessment Questionnaire-Disability Index (HAQ-DI) for difficulties in activities of daily living, and Pittsburgh Sleep Quality Index (PSQI) for sleep quality. Pearson and spearman's analysis were conducted to examine the relationship between systematic conditions and ocular surface conditions.

RESULTS

The analyses were controlled for age and sex. 52.22% of eyes (94 in 180) of autoimmune rheumatic patients and 21.67% of eyes (13 in 60) of controls were diagnosed with DED. The autoimmune rheumatic patients showed significant higher OSDI score, fewer basal tear secretion, more severe CFS and conjunctivochalasis than controls. There were no statistically significant differences in TBUT, meibomian gland secretion, symblepharon, and corneal clarity between the two groups. For systematic conditions, autoimmune rheumatic patients had significantly lower SF-36 scores, higher anxiety scores, and HAQ-DI scores than controls. No statistically significant differences were detected in depression scores and PSQI between the two groups. Among autoimmune rheumatic patients, OSDI scores were moderately correlated with quality of life, anxiety, depression and sleep quality.

CONCLUSION

Factors including quality of life, anxiety, depression, and sleep quality are associated with ocular surface conditions, especially DED symptoms. Management of systemic conditions and psychotherapy should also be considered as part of the treatment among autoimmune rheumatic patients.

Preclinical characterization of the Toll-like receptor 7/8 antagonist MHV370 for lupus therapy

Genetic and in vivo evidence suggests that aberrant recognition of RNA-containing autoantigens by Toll-like receptors (TLRs) 7 and 8 drives autoimmune diseases. Here we report on the preclinical characterization of MHV370, a selective oral TLR7/8 inhibitor. In vitro, MHV370 inhibits TLR7/8-dependent production of cytokines in human and mouse cells, notably interferon-α, a clinically validated driver of autoimmune diseases. Moreover, MHV370 abrogates B cell, plasmacytoid dendritic cell, monocyte, and neutrophil responses downstream of TLR7/8. In vivo, prophylactic or therapeutic administration of MHV370 blocks secretion of TLR7 responses, including cytokine secretion, B cell activation, and gene expression of, e.g., interferon-stimulated genes. In the NZB/W F1 mouse model of lupus, MHV370 halts disease. Unlike hydroxychloroquine, MHV370 potently blocks interferon responses triggered by specific immune complexes from systemic lupus erythematosus patient sera, suggesting differentiation from clinical standard of care. These data support advancement of MHV370 to an ongoing phase 2 clinical trial.

Immunosuppressive Polymeric Nanoparticles Targeting Dendritic Cells Alleviate Lupus Disease in Fcgr2b-/- Mice by Mediating Antigen-Specific Immune Tolerance

Dendritic cells (DCs) are the most potent antigen-presenting cells that have multifaceted functions in the control of immune activation and tolerance. Hyperresponsiveness and altered tolerogenicity of DCs contribute to the development and pathogenesis of system lupus erythematosus (SLE); therefore, DC-targeted therapies aimed at inducing specific immune tolerance have become of great importance for the treatment of SLE. This study developed a new nanoparticle (NP) containing a biodegradable PDMAEMA-PLGA copolymer for target-oriented delivery to DCs in situ. PDMAEMA-PLGA NPs provided sustained drug release and exhibited immunosuppressive activity in FLT3L and GM-CSF-derived bone marrow in conventional DCs (BM-cDCs). PDMAEMA-PLGA NPs improved dexamethasone capability to convert wild-type and Fcgr2b^-/- BM-cDCs from an immunogenic to tolerogenic state, and BM-cDCs treated with dexamethasone-incorporated PDMAEMA-PLGA NPs (Dex-NPs) efficiently mediated regulatory T cell (Treg) expansion in vitro. Dex-NP therapy potentially alleviated lupus disease in Fcgr2b^-/- mice by mediating Foxp3⁺ Treg expansion in an antigen-specific manner. Our findings substantiate the superior efficacy of DC-targeted therapy using the PDMAEMA-PLGA NP delivery system and provide further support for clinical development as a potential therapy for SLE. Furthermore, PDMAEMA-PLGA NP may be a versatile platform for DC-targeted therapy to induce antigen-specific immune tolerance to unwanted immune responses that occur in autoimmune disease, allergy, and transplant rejection.

Belimumab versus anifrolumab in adults with systemic lupus erythematosus: an indirect comparison of clinical response at 52 weeks

OBJECTIVE

To generate comparative efficacy evidence of belimumab versus anifrolumab in SLE that can inform treatment practices.

METHODS

The SLE Responder Index (SRI)-4 response at 52 weeks of belimumab versus anifrolumab was evaluated with an indirect treatment comparison. The evidence base consisted of randomised trials that were compiled through a systemic literature review.A feasibility assessment was performed to comprehensively compare the eligible trials and to determine the most appropriate indirect treatment comparison analysis method. A multilevel network meta-regression (ML-NMR) was implemented that adjusted for differences across trials in four baseline characteristics: SLE Disease Activity Index-2K, anti-double-stranded DNA antibody positive, low complement (C)3 and low C4. Additional analyses were conducted to explore if the results were robust to different sets of baseline characteristics included for adjustment, alternative adjustment methods and changes to the trials included in the evidence base.

RESULTS

The ML-NMR included eight trials: five belimumab trials (BLISS-52, BLISS-76, NEA, BLISS-SC, EMBRACE) and three anifrolumab trials (MUSE, TULIP-1, TULIP-2). Belimumab and anifrolumab were comparable in terms of SRI-4 response (OR (95% credible interval), 1.04 (0.74-1.45)), with the direction of the point estimate slightly favouring belimumab. Belimumab had a 0.58 probability of being the more effective treatment. The results were highly consistent across all analysis scenarios.

CONCLUSIONS

Our results suggest that the SRI-4 response of belimumab and anifrolumab are similar at 52 weeks in the general SLE population, but the level of uncertainty around the point estimate means we cannot rule out the possibility of a clinically meaningful benefit for either treatment. It remains to be seen if specific groups of patients could derive a greater benefit from anifrolumab or from belimumab, and there is certainly an unmet need to identify robust predictors towards more personalised selection of available biological agents in SLE.

Lupus Nephritis: New and Emerging Biologic and Targeted Therapies

Lupus nephritis (LN) is a severe complication of systemic lupus erythematosus (SLE), a polyclonal systemic autoimmunity directed against nuclear and other self-antigens. SLE/LN affects mostly females during childbearing age, which puts them at risk for the progression of chronic kidney disease (CKD), cardiovascular disease, and pregnancy complications. The current management of LN involves the use of drugs with significant toxicities, and despite many attempts at novel drug interventions, the overall treatment efficacy has remained low. In this article, we discuss recent drug approvals and the upcoming pipeline of novel medications tested in clinical trials to improve effectiveness in terms of LN disease activity, LN relapse, and progression of LN-related CKD. In this context, we discuss (1) drugs with the potential to achieve these treatment goals by modulating SLE activity as the driving force for LN (e.g., belimumab, obinutuzumab, anifrolumab, and others); (2) drugs with SLE-non specific renoprotective effects by targeting non-immune mechanisms of LN progression (dapagliflozin, empagliflozin); and (3) drugs with dual immunosuppressive and antiproteinuric effects (voclosporin). Increasing the number of possible drug options will help to improve the management of LN in terms of efficacy and safety, and enable a more personalized treatment approach.

Clinicopathologic features in childhood-onset lupus nephritis with antineutrophil cytoplasmic antibody positivity--a multi-center retrospective study

BACKGROUND

Positive antineutrophil cytoplasmic antibody (ANCA) serology in adult-onset lupus nephritis (LN) is associated with more active disease and distinct renal pathology, but data with respect to childhood-onset LN remain scarce. Here, we aimed to determine the impact of positive ANCA serology on clinical and histopathologic features and renal outcomes in children with LN from multiple centers.

METHODS

Clinical and histopathologic data of 61 ANCA-positive and 330 ANCA-negative LN children (1<age≤18 years) retrospectively enrolled from three pediatric nephrology centers were analyzed. Among them, 217 children were followed and survival analysis was performed.

RESULTS

Among 61 ANCA-positive LN children, 86.9% of them had antimyeloperoxidase antibodies. Both ANCA-positive and ANCA-negative children had high disease activities with median SLEDAI-2K of 16 (13, 20). Hematuria was more prominent (urinary RBC +++ ∼ ++++: 45.9% vs 26.7%, p = 0.011), while fever (42.6% vs. 58.2%, p = 0.035), alopecia (3.3% vs. 14.5%, p = 0.019), photosensitivity (0% vs. 8.2%, p = 0.013), and pleurisy (4.9% vs. 15.8%, p = 0.026) were less common in ANCA-positive children. Higher proportions of segmental sclerosis (23.7% vs. 9.8%, p = 0.025), crescentic formation (36.4% vs. 16.3%, p = 0.009), and capillary wall thickening (24.5% vs. 11.0%, p = 0.01) were observed in biopsies of ANCA-positive children. Long-term renal survival did not differ significantly between two groups (p = 0.300).

CONCLUSIONS

Positive ANCA serology in LN children was associated with different clinical and histopathologic features compared to those with negative ANCA serology. Further studies are needed to clarify the pathogenic role of ANCAs in childhood-onset LN and confirm their association with prognosis.

Immune-mediated lung diseases: A narrative review

The role of immunity in the pathogenesis of various pulmonary diseases, particularly interstitial lung diseases (ILDs), is being increasingly appreciated as mechanistic discoveries advance our knowledge in the field. Immune-mediated lung diseases demonstrate clinical and immunological heterogeneity and can be etiologically categorized into connective tissue disease (CTD)-associated, exposure-related, idiopathic, and other miscellaneous lung diseases including sarcoidosis, and post-lung transplant ILD. The immunopathogenesis of many of these diseases remains poorly defined and possibly involves either immune dysregulation, abnormal healing, chronic inflammation, or a combination of these, often in a background of genetic susceptibility. The heterogeneity and complex immunopathogenesis of ILDs complicate management, and thus a collaborative treatment team should work toward an individualized approach to address the unique needs of each patient. Current management of immune-mediated lung diseases is challenging; the choice of therapy is etiology-driven and includes corticosteroids, immunomodulatory drugs such as methotrexate, cyclophosphamide and mycophenolate mofetil, rituximab, or other measures such as discontinuation or avoidance of the inciting agent in exposure-related ILDs. Antifibrotic therapy is approved for some of the ILDs (e.g., idiopathic pulmonary fibrosis) and is being investigated for many others and has shown promising preliminary results. A dire need for advances in the management of immune-mediated lung disease persists in the absence of standardized management guidelines.

TMM-Nets: Transferred Multi- to Mono-Modal Generation for Lupus Retinopathy Diagnosis

Rare diseases, which are severely underrepresented in basic and clinical research, can particularly benefit from machine learning techniques. However, current learning-based approaches usually focus on either mono-modal image data or matched multi-modal data, whereas the diagnosis of rare diseases necessitates the aggregation of unstructured and unmatched multi-modal image data due to their rare and diverse nature. In this study, we therefore propose diagnosis-guided multi-to-mono modal generation networks (TMM-Nets) along with training and testing procedures. TMM-Nets can transfer data from multiple sources to a single modality for diagnostic data structurization. To demonstrate their potential in the context of rare diseases, TMM-Nets were deployed to diagnose the lupus retinopathy (LR-SLE), leveraging unmatched regular and ultra-wide-field fundus images for transfer learning. The TMM-Nets encoded the transfer learning from diabetic retinopathy to LR-SLE based on the similarity of the fundus lesions. In addition, a lesion-aware multi-scale attention mechanism was developed for clinical alerts, enabling TMM-Nets not only to inform patient care, but also to provide insights consistent with those of clinicians. An adversarial strategy was also developed to refine multi- to mono-modal image generation based on diagnostic results and the data distribution to enhance the data augmentation performance. Compared to the baseline model, the TMM-Nets showed 35.19% and 33.56% F1 score improvements on the test and external validation sets, respectively. In addition, the TMM-Nets can be used to develop diagnostic models for other rare diseases.

Long-Term Opioid Therapy Among Patients With Systemic Lupus Erythematosus in the Community: A Lupus Midwest Network (LUMEN) Study

OBJECTIVE

There is little information about the epidemiology and factors associated with opioid therapy in systemic lupus erythematosus (SLE). We aimed to assess the prevalence of opioid therapy and explore factors associated with long-term opioid therapy (LTOT) in patients with SLE.

METHODS

Patients with SLE were matched with controls without SLE in a population-based cohort on January 1, 2015. We captured demographics, manifestations of SLE, comorbidities (ie, fibromyalgia, mood disorders, osteoarthritis, chronic low back pain [CLBP], chronic kidney disease (CKD), avascular necrosis, osteoporosis, fragility fractures, and cancer), and the Area Deprivation Index (ADI). Opioid prescription data were used to assess the prevalence of LTOT, defined as contiguous prescriptions (gaps of < 30 days between prescriptions) and receiving opioid therapy for ≥ 90 days or ≥ 10 prescriptions before the index date.

RESULTS

A total of 465 patients with SLE and 465 controls without SLE were included. In total, 13% of patients with SLE and 3% of controls without SLE were receiving opioid therapy (P < 0.001), and 11% of patients with SLE were on LTOT vs 1% of controls without SLE. Among patients with SLE, acute pericarditis (odds ratio [OR] 3.92, 95% CI 1.78-8.66), fibromyalgia (OR 7.78, 95% CI 3.89-15.55), fragility fractures (OR 3.72, 95% CI 1.25-11.07), CLBP (OR 4.00, 95% CI 2.13-7.51), and mood disorders (OR 2.76, 95% CI 1.47-5.16) were associated with LTOT. We did not find an association between opioid therapy and ADI.

CONCLUSION

Patients with SLE are more likely to receive LTOT than controls. Among patients with SLE, LTOT was associated with pericarditis and several comorbidities. However, LTOT was not associated with CKD despite the limited pain control options among these patients.

Endometriosis and Systemic Lupus Erythematosus: Systematic Review and Meta-analysis

Endometriosis is a chronic gynaecological condition characterized by inflammatory and immune abnormalities. Likewise, these dysfunctions are important hallmarks of systemic lupus erythematosus (SLE), a condition that also has a high prevalence among women in reproductive age. Therefore, we conducted a systematic review and meta-analysis to investigate the association between endometriosis and SLE. We searched Medline and Web of Science for articles published from database inception to March 1, 2021. Random-effects meta-analysis was performed to provide a pooled risk ratio (RR). Individual study quality was evaluated following the National Heart, Lung, and Blood Institute Quality Assessment Tools (NHLBI QAT). From the 225 articles identified through our search, five studies-assessing 152,355 women-were included. Included studies presented an overall poor or fair quality rating. We observed a significant association between endometriosis and SLE (RR = 2.47, 95% confidence interval: 1.33-4.59, P < 0.004, I2 = 54%). Sensitivity analyses stratifying articles by study design demonstrated that the association was significant in cross-sectional and case-control studies (RR = 5.07, 95% confidence interval: 1.42-18.11, P < 0.012), as well as in cohort studies (RR = 2.07, 95% confidence interval: 1.02-4.20, P < 0.044). In spite of the limited quality of included studies, our results suggest the existence of an association between endometriosis and SLE. These findings can aid medical assessment of patients with endometriosis, as well as provide further insights to better understand this gynaecological disorder.

Population Pharmacokinetics and Exposure-Response for Dapirolizumab Pegol From a Phase 2b Trial in Patients With Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a systemic, autoimmune disease characterized by chronic inflammation and organ damage. Dapirolizumab pegol inhibits CD40 ligand (CD40L) and is currently undergoing phase 3 trials for the treatment of SLE. To describe the pharmacokinetic characteristics of dapirolizumab pegol and the relationship between exposure and probability of achieving a British Isles Lupus Assessment Group-based Composite Lupus Assessment (BICLA) response, a population pharmacokinetic (popPK) model and an exposure-response model were developed, based on results of the phase 2b trial (RISE; NCT02804763) of dapirolizumab pegol in SLE. Dapirolizumab pegol pharmacokinetics were found to be dose proportional and well described by a 2-compartment model with first-order elimination from the central compartment. In the popPK model, body weight was the only significant covariate. The average concentration of dapirolizumab pegol, derived from the popPK model, was incorporated into the exposure-response model. Overall, the exposure-response model showed that treatment with dapirolizumab pegol increased the probability of transitioning from BICLA "Nonresponder" to "Responder." No significant covariates on BICLA responder status were identified. Notably, the half maximal effective concentration was greater for the transition from "Responder" to "Nonresponder" (150 µg/mL) than the transition from "Nonresponder" to "Responder" (12 µg/mL), indicating that sustained dapirolizumab pegol concentrations may be required to maintain BICLA response. In conclusion, dapirolizumab pegol pharmacokinetics were as expected for a PEGylated molecule and results from the exposure-response model indicate that a favorable dapirolizumab pegol effect was identified for both BICLA "Nonresponder" to "Responder" and "Responder" to "Nonresponder" transition probabilities.

Potential Therapeutic Value of the STING Inhibitors

The stimulator of interferon genes (STING) is a critical protein in the activation of the immune system in response to DNA. It can participate the inflammatory response process by modulating the inflammation-preferred translation program through the STING-PKR-like endoplasmic reticulum kinase (PERK)-eIF2α pathway or by inducing the secretion of type I interferons (IFNs) and a variety of proinflammatory factors through the recruitment of TANK-binding kinase 1 (TBK1) and interferon regulatory factor 3 (IRF3) or the regulation of the nuclear factor kappa-B (NF-κB) pathway. Based on the structure, location, function, genotype, and regulatory mechanism of STING, this review summarizes the potential value of STING inhibitors in the prevention and treatment of infectious diseases, psoriasis, systemic lupus erythematosus, non-alcoholic fatty liver disease, and other inflammatory and autoimmune diseases.

Spleen fibroblastic reticular cell-derived acetylcholine promotes lipid metabolism to drive autoreactive B cell responses

Autoreactive B cell responses are essential for the development of systemic lupus erythematosus (SLE). Fibroblastic reticular cells (FRCs) are known to construct lymphoid compartments and regulate immune functions. Here, we identify spleen FRC-derived acetylcholine (ACh) as a key factor that controls autoreactive B cell responses in SLE. In SLE, CD36-mediated lipid uptake leads to enhanced mitochondrial oxidative phosphorylation in B cells. Accordingly, the inhibition of fatty acid oxidation results in reduced autoreactive B cell responses and ameliorated diseases in lupus mice. Ablation of CD36 in B cells impairs lipid uptake and differentiation of autoreactive B cells during autoimmune induction. Mechanistically, spleen FRC-derived ACh promotes lipid influx and generation of autoreactive B cells through CD36. Together, our data uncover a novel function of spleen FRCs in lipid metabolism and B cell differentiation, placing spleen FRC-derived ACh in a key position in promoting autoreactive B cells in SLE.

Short-term prognostic analysis of patients with systemic lupus erythematosus co-infection and comparison of mNGS and conventional microbiological test results

Objectives

Infection is one of the major causes of morbidity and mortality in patients with systemic lupus erythematosus (SLE), and as a new diagnostic technique, metagenomic next-generation sequencing (mNGS) is increasingly used for the pathogenetic detection of co-infected SLE patients. However, conventional microbiological testing (CMT) is still the gold standard for pathogenic diagnosis, and the specific diagnostic efficacy of mNGS versus CMT in such patients is not known. In addition, there are few studies on the short-term prognosis of co-infected SLE patients.

Methods

This study retrospectively included 58 SLE patients with co-infection admitted to the First Affiliated Hospital of Zhengzhou University from October 2020 to August 2022. Patients were divided into a survivors (n=27) and a non-survivors (n=31) according to their discharge status. Baseline characteristics and etiological data were collected and statistically analyzed for all patients during their hospitalization. The sequential organ failure assessment (SOFA) score, acute physiology and chronic health evaluation (APACHE) II and systemic lupus erythematosus disease activity index (SLEDAI) were calculated for each patient to assess the predictive ability of the 3 scores on the short-term prognosis of SLE patients. The mNGS and CMT culture results were also compared to clarify the flora characteristics of patients with SLE infection.

Results

More patients in the non-survivors had renal impairment, neurological manifestations, multiplasmatic cavity effusion and gastrointestinal manifestations compared to the survivors (p &lt; 0.05). The SOFA score, APACHE II and SLEDAI were significantly higher in the non-survivors than in the survivors (p &lt; 0.01). There were also significant differences between the two groups in several tests such as hemoglobin, platelets, albumin, total bilirubin, C-reactive protein (CRP), procalcitonin (PCT), and complement C3 (p &lt; 0.05). In addition, the absolute values of T lymphocytes, CD4+ T cells and CD8+ T cells were smaller in the non-survivors than in the survivors (p &lt; 0.05). The most common type of infection in this study was pulmonary infection, followed by bloodstream infection. mNGS and CMT positivity rates were not significantly different among patients in the non-survivors, but were significantly different among patients in the survivors (p=0.029). In-hospital survival of patients with SLE infection could be predicted based on the SOFA score in relation to 6. For patients with SOFA &lt;6, we recommend earlier mNGS testing to identify the pathogen and improve patient prognosis.

Conclusions

For SLE patients with co-infection, in-hospital survival can be predicted based on SOFA score. For patients with SOFA &lt;6, advising them to complete mNGS testing as early as possible may improve the prognosis to some extent.

Functional Genome Analysis for Immune Cells Provides Clues for Stratification of Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is caused by a combination of genetic and environmental factors. Recently, analysis of a functional genome database of genetic polymorphisms and transcriptomic data from various immune cell subsets revealed the importance of the oxidative phosphorylation (OXPHOS) pathway in the pathogenesis of SLE. In particular, activation of the OXPHOS pathway is persistent in inactive SLE, and this activation is associated with organ damage. The finding that hydroxychloroquine (HCQ), which improves the prognosis of SLE, targets toll-like receptor (TLR) signaling upstream of OXPHOS suggests the clinical importance of this pathway. IRF5 and SLC15A4, which are regulated by polymorphisms associated with SLE susceptibility, are functionally associated with OXPHOS as well as blood interferon activity and metabolome. Future analyses of OXPHOS-associated disease-susceptibility polymorphisms, gene expression, and protein function may be useful for risk stratification of SLE.

The Role of Viral Infections in the Onset of Autoimmune Diseases

Autoimmune diseases (AIDs) are the consequence of a breach in immune tolerance, leading to the inability to sufficiently differentiate between self and non-self. Immune reactions that are targeted towards self-antigens can ultimately lead to the destruction of the host's cells and the development of autoimmune diseases. Although autoimmune disorders are comparatively rare, the worldwide incidence and prevalence is increasing, and they have major adverse implications for mortality and morbidity. Genetic and environmental factors are thought to be the major factors contributing to the development of autoimmunity. Viral infections are one of the environmental triggers that can lead to autoimmunity. Current research suggests that several mechanisms, such as molecular mimicry, epitope spreading, and bystander activation, can cause viral-induced autoimmunity. Here we describe the latest insights into the pathomechanisms of viral-induced autoimmune diseases and discuss recent findings on COVID-19 infections and the development of AIDs.

Radiation from UV-A to Red Light Induces ROS-Dependent Release of Neutrophil Extracellular Traps

Neutrophils release decondensed chromatin or extracellular traps (NETs) in response to various physiological and pharmacological stimuli. Apart from host defensive functions, NETs play an essential role in the pathogenesis of various autoimmune, inflammatory, and malignant diseases. In recent years, studies have been performed on photo-induced NET formation, mainly activated by UV radiation. Understanding the mechanisms of NET release under the influence of UV and visible light is important to control the consequences of the damaging effects of electromagnetic radiation. Raman spectroscopy was applied to record characteristic Raman frequencies of various reactive oxygen species (ROS) and low-frequency lattice vibrational modes for citrulline. NETosis was induced by irradiation with wavelength-switchable LED sources. Fluorescence microscopy was used to visualize and quantify NET release. The ability of five wavelengths of radiation, from UV-A to red light, to induce NETosis was investigated at three different energy doses. We demonstrated, for the first time, that NET formation is activated not only by UV-A but also by three spectra of visible light: blue, green, and orange, in a dose-dependent manner. Using inhibitory analysis, we established that light-induced NETosis proceeds through NADPH oxidase and PAD4. The development of new drugs designed to suppress NETosis, especially when induced by exposure to intense UV and visible light, can help to mitigate light-induced photoaging and other damaging effects of electromagnetic radiation.

Host-derived mannose glycans trigger a pathogenic γδ T cell/IL-17a axis in autoimmunity

Autoimmune diseases are life-threatening disorders that cause increasing disability over time. Systemic lupus erythematosus (SLE) and other autoimmune diseases arise when immune stimuli override mechanisms of self-tolerance. Accumulating evidence has demonstrated that protein glycosylation is substantially altered in autoimmune disease development, but the mechanisms by which glycans trigger these autoreactive immune responses are still largely unclear. In this study, we found that presence of microbial-associated mannose structures at the surface of the kidney triggers the recognition of DC-SIGN-expressing γδ T cells, inducing a pathogenic interleukin-17a (IL-17a)-mediated autoimmune response. Mice lacking Mgat5, which have a higher abundance of mannose structures in the kidney, displayed increased γδ T cell infiltration into the kidney that was associated with spontaneous development of lupus in older mice. N-acetylglucosamine supplementation, which promoted biosynthesis of tolerogenic branched N-glycans in the kidney, was found to inhibit γδ T cell infiltration and control disease development. Together, this work reveals a mannose-γδ T cell-IL-17a axis in SLE immunopathogenesis and highlights glycometabolic reprogramming as a therapeutic strategy for autoimmune disease treatment.

Adaptation and validation of the Bulgarian version of the Systemic Lupus Erythematosus Quality of Life Questionnaire (L-QoL)

OBJECTIVE

Systemic lupus erythematosus (SLE) is a heterogeneous disease with multiple clinical manifestations, which causes a significant deterioration in the quality of life (QoL). The Systemic Lupus Erythematosus Quality of Life Questionnaire (L-QoL) is a lupus-specific measure used to determine the burden of the disease and it applies the need-based model of QoL. Our aim was to produce the first successfully validated foreign language version of the questionnaire.

METHODS

The development of the Bulgarian version involved three stages: translation, field testing and psychometric evaluation. Translation was conducted by an expert linguist working with a developer of the original L-QoL, followed by interviews with monolingual lay individuals. Face and content validity of the translation were assessed by cognitive debriefing interviews with Bulgarian SLE patients. Finally, the L-QoL was validated by administering the questionnaire to a random sample of SLE patients on two occasions, 2 weeks apart to evaluate its reliability and validity.

RESULTS

In the validation survey, the new Bulgarian version demonstrated high internal consistency (the Cronbach's alpha coefficient was 0.92), and test-retest reliability (0.97). Additionally, scores on the L-QoL were correlated with those on the SF-36 sections to determine convergent validity and the strongest correlation was observed between L-QoL scores and the social functioning section of the SF-36. Known group validity was established by testing the ability of the Bulgarian L-QoL to distinguish between subgroups of patients from the study pool.

CONCLUSIONS

The demonstrated excellent psychometric properties ensure that the Bulgarian L-QoL accurately captures the impact of SLE on the quality of life. Key points • The Bulgarian version of the L-QoL is a valid and reliable measure of QoL in lupus patients. • The Bulgarian version of the L-QoL can be used as an outcome measure in research, clinical trials and routine clinical practice.

Zetomipzomib (KZR-616) attenuates lupus in mice via modulation of innate and adaptive immune responses

Zetomipzomib (KZR-616) is a selective inhibitor of the immunoproteasome currently undergoing clinical investigation in autoimmune disorders. Here, we characterized KZR-616 in vitro and in vivo using multiplexed cytokine analysis, lymphocyte activation and differentiation, and differential gene expression analysis. KZR-616 blocked production of &gt;30 pro-inflammatory cytokines in human peripheral blood mononuclear cells (PBMCs), polarization of T helper (Th) cells, and formation of plasmablasts. In the NZB/W F1 mouse model of lupus nephritis (LN), KZR-616 treatment resulted in complete resolution of proteinuria that was maintained at least 8 weeks after the cessation of dosing and was mediated in part by alterations in T and B cell activation, including reduced numbers of short and long-lived plasma cells. Gene expression analysis of human PBMCs and tissues from diseased mice revealed a consistent and broad response focused on inhibition of T, B, and plasma cell function and the Type I interferon pathway and promotion of hematopoietic cell lineages and tissue remodeling. In healthy volunteers, KZR-616 administration resulted in selective inhibition of the immunoproteasome and blockade of cytokine production following ex vivo stimulation. These data support the ongoing development of KZR-616 in autoimmune disorders such as systemic lupus erythematosus (SLE)/LN.

Cytotoxic CD161-CD8+ TEMRA cells contribute to the pathogenesis of systemic lupus erythematosus

BACKGROUND

Systemic lupus erythematosus (SLE) is a prototypical autoimmune disease affecting multiple organs and tissues with high cellular heterogeneity. CD8⁺ T cell activity is involved in the SLE pathogenesis. However, the cellular heterogeneity and the underlying mechanisms of CD8⁺ T cells in SLE remain to be identified.

METHODS

Single-cell RNA sequencing (scRNA-seq) of PBMCs from a SLE family pedigree (including 3 HCs and 2 SLE patients) was performed to identify the SLE-associated CD8⁺ T cell subsets. Flow cytometry analysis of a SLE cohort (including 23 HCs and 33 SLE patients), qPCR analysis of another SLE cohort (including 30 HCs and 25 SLE patients) and public scRNA-seq datasets of autoimmune diseases were employed to validate the finding. Whole-exome sequencing (WES) of this SLE family pedigree was used to investigate the genetic basis in dysregulation of CD8⁺ T cell subsets identified in this study. Co-culture experiments were performed to analyze the activity of CD8⁺ T cells.

FINDINGS

We elucidated the cellular heterogeneity of SLE and identified a new highly cytotoxic CD8⁺ T cell subset, CD161^-CD8⁺ T_EMRA cell subpopulation, which was remarkably increased in SLE patients. Meanwhile, we discovered a close correlation between mutation of DTHD1 and the abnormal accumulation of CD161^-CD8⁺ T_EMRA cells in SLE. DTHD1 interacted with MYD88 to suppress its activity in T cells and DTHD1 mutation promoted MYD88-dependent pathway and subsequently increased the proliferation and cytotoxicity of CD161^-CD8⁺ T_EMRA cells. Furthermore, the differentially expressed genes in CD161^-CD8⁺ T_EMRA cells displayed a strong out-of-sample prediction for case-control status of SLE.

INTERPRETATION

This study identified DTHD1-associated expansion of CD161^-CD8⁺ T_EMRA cell subpopulation is critical for SLE. Our study highlights genetic association and cellular heterogeneity of SLE pathogenesis and provides a mechanistical insight into the diagnosis and treatment of SLE.

FUNDINGS

Stated in the Acknowledgements section of the manuscript.