Blockade of OX40/OX40L signaling using anti-OX40L alleviates murine lupus nephritis.

Genetic variants of the OX40 ligand (OX40L) locus are associated with the risk of systemic lupus erythematosus (SLE), it is unclear how the OX40L blockade delays the lupus phenotype. Therefore, we examined the effects of an anti-OX40L antibody in MRL/Lpr mice. Next, we investigated the effect of anti-OX40L on immunosuppression in keyhole limpet hemocyanin-immunized C57BL/6J mice. In vitro treatment of anti-OX40L in CD4+ T and B220+ B cells was used to explore the role of OX40L in the pathogenesis of SLE. Anti-OX40L alleviated murine lupus nephritis, accompanied by decreased production of anti-dsDNA and proteinuria, as well as lower frequencies of splenic T helper (Th) 1 and T-follicular helper cells (Tfh). In keyhole limpet hemocyanin-immunized mice, decreased levels of immunoglobulins and plasmablasts were observed in the anti-OX40L group. Anti-OX40L reduced the number and area of germinal centers. Compared with the control IgG group, anti-OX40L downregulated CD4+ T-cell differentiation into Th1 and Tfh cells and upregulated CD4+ T-cell differentiation into regulatory T cells in vitro. Furthermore, anti-OX40L inhibited toll-like receptor 7-mediated differentiation of antibody-secreting cells and antibody production through the regulation of the SPIB-BLIMP1-XBP1 axis in B cells. These results suggest that OX40L is a promising therapeutic target for SLE.

Understanding the pathogenic significance of altered calcium-calmodulin signaling in T cells in autoimmune diseases.

Calcium/calmodulin-dependent protein kinase IV (CaMK4) serves as a pivotal mediator in the regulation of gene expression, influencing the activity of transcription factors within a variety of immune cells, including T cells. Altered CaMK4 signaling is implicated in autoimmune diseases such as systemic lupus erythematosus, rheumatoid arthritis, and psoriasis, which are characterized by dysregulated immune responses and clinical complexity. These conditions share common disturbances in immune cell functionality, cytokine production, and autoantibody generation, all of which are associated with disrupted calcium-calmodulin signaling. This review underscores the consequences of dysregulated CaMK4 signaling across these diseases, with an emphasis on its impact on Th17 differentiation and T cell metabolism-processes central to maintaining immune homeostasis. A comprehensive understanding of roles of CaMK4 in gene regulation across various autoimmune disorders holds promise for the development of targeted therapies, particularly for diseases driven by Th17 cell dysregulation.

UNCovering new causes of monogenic systemic lupus erythematosus.

UNC93B1 is essential for the stability and endosomal trafficking of nucleic-acid sensing Toll-like receptors (TLRs) including TLR7 and TLR8. Increased TLR7 responses are associated with lupus autoimmunity in both mice and humans. In a recent article, Al-Azab et al. demonstrate the role of a variant of UNC93B1 (p.V117L) in the induction of pediatric systemic lupus erythematosus in patients and in mice through TLR7/8 hyperresponsiveness. They also highlight a potential role for the pharmacological inhibition of interleukin-1 receptor-associated kinase (IRAK) 1 and/or 4 in ameliorating disease.

Disruption of memory B-cell trafficking by belimumab in patients with systemic lupus erythematosus.

OBJECTIVES: Autoreactive memory B cells contribute to chronic and progressive courses in autoimmune diseases like systemic lupus erythematosus (SLE). The efficacy of belimumab (BEL), the first approved biologic treatment for SLE and lupus nephritis (LN), is generally attributed to depletion of activated naïve B cells and inhibition of B cell activation. BEL's effect on memory B cells (MBCs) is currently unexplained. We performed an in-depth cellular and transcriptomic analysis of BEL's impact on the blood MBC compartment in patients with SLE. METHODS: A retrospective meta-analysis was conducted, pooling flow cytometry data from four randomized trials involving 1245 patients with SLE treated with intravenous BEL or placebo. Then, extensive MBC phenotyping was performed using high-sensitivity flow cytometry in patients with mild/moderate SLE and severe SLE/LN treated with subcutaneous BEL. Finally, transcriptomic characterization of surging MBCs was performed by single-cell RNA sequencing. RESULTS: In BEL-treated patients, a significant increase in circulating MBCs, in a broad range of MBC subsets, was established at week 2, gradually returning to baseline by week 52. The increase was most prominent in patients with higher SLE disease activity, serologically active patients, and patients aged ≤18 years. MBCs had a non-proliferating phenotype with a prominent decrease in activation status and downregulation of numerous migration genes. CONCLUSION: Upon BEL initiation, an increase of MBCs was firmly established. In the small cohort investigated, circulating MBCs were de-activated, non-proliferative, and demonstrated characteristics of disrupted lymphocyte trafficking, expanding on our understanding of the therapeutic mechanism of B cell-activating factor inhibition by BEL. TRIAL REGISTRATION: ClinicalTrials.gov NCT00071487, NCT00410384, NCT01632241, NCT01649765, NCT03312907, NCT03747159.

A glance on the role of IL-35 in systemic lupus erythematosus (SLE).

It is well known that systemic lupus erythematosus (SLE) is an auto-inflammatory disease that is characterized by chronic and widespread inflammation. The exact pathogenesis of SLE is still a matter of debate. However, it has been suggested that the binding of autoantibodies to autoantigens forms immune complexes (ICs), activators of the immune response, in SLE patients. Ultimately, all of these responses lead to an imbalance between anti-inflammatory and pro-inflammatory cytokines, resulting in cumulative inflammation. IL-35, the newest member of the IL-12 family, is an immunosuppressive and anti-inflammatory cytokine secreted mainly by regulatory cells. Structurally, IL-35 is a heterodimeric cytokine, composed of Epstein-Barr virus-induced gene 3 (EBI3) and p35. IL-35 appears to hold therapeutic and diagnostic potential in cancer and autoimmune diseases. In this review, we summarized the most recent associations between IL and 35 and SLE. Unfortunately, the comparative review of IL-35 in SLE indicates many differences and contradictions, which make it difficult to generalize the use of IL-35 in the treatment of SLE. With the available information, it is not possible to talk about targeting this cytokine for the lupus treatment. So, further studies would be needed to establish the clear and exact levels of this cytokine and its related receptors in people with lupus to provide IL-35 as a preferential therapeutic or diagnostic candidate in SLE management.

IFN-γ and androgens disrupt mitochondrial function in murine myocytes.

The effect of cytokines on non-traditional immunological targets under conditions of chronic inflammation is an ongoing subject of study. Fatigue is a symptom often associated with autoimmune diseases. Chronic inflammatory response and activated cell-mediated immunity are associated with cardiovascular myopathies which can be driven by muscle weakness and fatigue. Thus, we hypothesize that immune dysfunction-driven changes in myocyte mitochondria may play a critical role in fatigue-related pathogenesis. We show that persistent low-level expression of IFN-γ in designated IFN-γ AU-Rich Element deletion mice (ARE mice) under androgen exposure resulted in mitochondrial and metabolic deficiencies in myocytes from male or castrated ARE mice. Most notably, echocardiography unveiled that low ejection fraction in the left ventricle post-stress correlated with mitochondrial deficiencies, explaining how heart function decreases under stress. We report that inefficiencies and structural changes in mitochondria, with changes to expression of mitochondrial genes, are linked to male-biased fatigue and acute cardiomyopathy under stress. Our work highlights how male androgen hormone backgrounds and active autoimmunity reduce mitochondrial function and the ability to cope with stress and how pharmacological blockade of stress signal protects heart function. These studies provide new insight into the diverse actions of IFN-γ in fatigue, energy metabolism, and autoimmunity. © 2023 The Pathological Society of Great Britain and Ireland. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.

Causal effects of endometriosis on SLE, RA and SS risk: evidence from meta-analysis and Mendelian randomization.

BACKGROUND: Endometriosis is an underdiagnosed disorder that affects an estimated 6-10% of women of reproductive age. Endometriosis has been reported in epidemiological studies to be associated with autoimmune diseases. However, the relationship remains controversial. METHODS: A meta-analysis of observational studies was undertaken to evaluate the risk of autoimmune diseases in patients with endometriosis. The relevant studies were retrieved via the databases Medline, Embase and Web of Science until July 20, 2023. Mendelian randomization (MR) was subsequently utilized to scrutinize the causal influence of genetic predisposition toward endometriosis on three autoimmune diseases. RESULTS: The meta-analysis findings revealed a relationship between endometriosis and the onset of SLE (cohort studies: RR = 1.77, 95% confidence interval (CI): 1.47-2.13, I2 = 0%; Case-control and cross-sectional studies: OR = 5.23, 95% CI: 0.74-36.98, I2 = 98%), RA (cohort studies: RR = 2.18, 95% CI: 1.85-2.55, I2 = 92%; Case-control and cross-sectional studies: OR = 1.40, 95% CI: 1.19-1.64, I2 = 0%) and SS (cohort studies: RR = 1.49, 95% CI: 1.34-1.66, I2 = 0%). Similarly, in our MR study, the results of the inverse-variance-weighted (IVW) model suggested that genetic predisposition to endometriosis was causally associated with an increased risk for SLE (OR = 1.915, 95% CI: 1.204-3.045, p = 0.006) and RA (OR = 1.005, 95% CI: 1.001-1.009, p = 0.014). CONCLUSIONS: Both our meta-analysis and MR study indicate that endometriosis increases the risk of autoimmune diseases. These findings not only broaden our understanding of the genetic mechanisms underlying the comorbidity of endometriosis and autoimmune diseases, but also offer a new strategy for autoimmune disease prevention.

Systemic lupus erythematosus presenting with atypical hemolytic uremic syndrome: a case report and review of the literature.

Systemic lupus erythematosus (SLE) can present with a diverse array of hematologic manifestations, among which atypical hemolytic uremic syndrome (aHUS) is a rare entity. SLE-triggered aHUS has significant morbidity and mortality without timely intervention, yet its frequency remains uncertain and optimal strategies for complement-directed therapies are largely expert-driven. We performed a comprehensive literature review and present a case of a 23-year-old female newly diagnosed with SLE/class IV lupus nephritis who developed aHUS that rapidly responded to the C5 antagonist, eculizumab. Review of the current literature identified forty-nine published cases of SLE with concurrent aHUS and revealed a predilection for aHUS in younger SLE patients, concurrent presentation with lupus nephritis, anti-dsDNA positivity, and complement system abnormalities. Over seventy percent of cases used eculizumab as complement-directed therapy with a trend towards faster time to improvement in laboratory parameters, though reported outcomes were highly variable. Early recognition of aHUS in SLE is pivotal in guiding appropriate therapeutic interventions, and prompt initiation of eculizumab may reduce the potential morbidity associated with plasmapheresis and additional immunosuppression. While eculizumab showcases promising results, its optimal timing and duration remain elusive. An understanding of a patients' complement genetics could aid management strategies, and ongoing research into complement-targeted therapies offers promising avenues for both SLE and aHUS treatment.

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

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

[Current patient care of systematic lupus erythematosus in Rhineland-Palatinate and Saarland]. / Versorgungssituation des Systemischen Lupus Erythematodes in Rheinland-Pfalz und dem 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..

Phosphatidylserine-Dependent Anti-prothrombin Antibodies as a Key Predictor for Systemic Lupus Erythematosus in Patients with Primary Antiphospholipid Syndrome: A retrospective longitudinal cohort study.

OBJECTIVES: Primary antiphospholipid syndrome (PAPS) is an autoimmune disorder characterized by thrombosis and pregnancy morbidity. Although PAPS is distinct from systemic lupus erythematosus (SLE), the two conditions share clinical features and susceptibility genes. Progression from PAPS to SLE is well-recognized. However, risk factors for this transition are poorly understood. We aimed to identify predictors of progression to SLE in patients with PAPS. METHODS: A longitudinal single-center study was conducted at Hokkaido University Hospital from 1990 to 2021. Baseline characteristics including clinical features, laboratory data, aPL profiles were compared between patients who progressed to SLE (SLE group) and those who did not (non-SLE group). RESULTS: Among 64 patients diagnosed with PAPS at baseline, nine (13.8%) progressed to SLE over a mean follow-up of 9 years (incidence rate, 1.61 per 100 person-years). At the diagnosis of PAPS, the SLE group had a higher prevalence of anti-phosphatidylserine/prothrombin antibodies (aPS/PT) and anti-dsDNA antibodies compared to the non-SLE group. Other clinical findings, autoantibody profiles, and serum complement levels were similar between the two groups. Multivariate Cox analysis showed that IgG aPS/PT was significantly associated with SLE development (Hazard ratio: 10.3, 95% CI: 1.13-92.6, p=0.04). CONCLUSION: IgG aPS/PT may be a predictive factor for new-onset SLE in patients with PAPS, suggesting its utility in guiding risk stratification and monitoring strategies for these patients.

A young lady presenting with acute limb ischemia secondary to systemic lupus erythematosus, antiphospholipid syndrome and infective endocarditis.

We report a case of a 35 years old lady presenting with acute upper limb ischemia secondary to systemic lupus erythematosus (SLE), antiphospholipid syndrome (APLS) and infective endocarditis (IE). It is rare for SLE/APLS to present with acute limb ischemia (ALI) as the initial manifestation. The patient presented with high grade fever along with pain and numbness in her right upper limb. On examination her right upper limb was cold to touch and the peripheral pulses were not palpable. There was also an audible pansystolic murmur in the mitral area. CT Angiography confirmed a complete occlusion of the right axillary artery while echocardiogram revealed severe mitral regurgitation with large vegetations on the mitral valve leaflets, suggesting infective endocarditis. After the patient's clinical deterioration and considering the severity of the ischemic condition, additional investigations were conducted, which ultimately led to the diagnosis of SLE with APLS. Management included antibiotic therapy for IE and high dose of IV steroids and anticoagulants for SLE/APLS, to which she responded well. This case emphasizes the significance of conducting a comprehensive evaluation of all possible causes of acute limb ischemia, while considering the patient's medical history and physical examination findings.

Phenotypic Variability in PRKCD: a Review of the Literature.

PURPOSE: Protein kinase C δ (PKCδ) deficiency is a rare genetic disorder identified as a monogenic cause of systemic lupus erythematosus in 2013. Since the first cases were described, the phenotype has expanded to include children presenting with autoimmune lymphoproliferative syndrome-related syndromes and infection susceptibility similar to chronic granulomatous disease or combined immunodeficiency. We review the current published data regarding the pathophysiology, clinical presentation, investigation and management of PKCδ deficiency. METHODS: Literature review was performed using MEDLINE. RESULTS: Twenty cases have been described in the literature with significant heterogeneity. CONCLUSION: The variation in clinical presentation delineates the broad and critical role of PKCδ in immune tolerance and effector functions against pathogens.

Splicing machinery is profoundly altered in systemic lupus erythematosus and antiphospholipid syndrome and directly linked to key clinical features.

OBJECTIVES: To characterize the splicing machinery (SM) of leukocytes from primary antiphospholipid syndrome (APS), systemic lupus erythematosus (SLE) and antiphospholipid syndrome with lupus (APS + SLE) patients, and to assess its clinical involvement. METHODS: Monocytes, lymphocytes and neutrophils from 80 patients (22 APS, 35 SLE and 23 APS + SLE) and 50 HD were purified, and 45 selected SM components were evaluated by qPCR-microfluidic array. Relationship with clinical features and underlying regulatory mechanisms were assessed. RESULTS: APS, SLE and APS + SLE leukocytes displayed significant and specific alterations in SM-components (SMC), associated with clinical features [autoimmune profiles, disease activity, lupus nephritis (LN), and CV-risk markers]. A remarkable relationship among dysregulated SMC in monocytes and the presence of LN in SLE was highlighted, revealing a novel pathological mechanism, which was further explored. Immunohistology analysis of renal biopsies highlighted the pathological role of the myeloid compartment in LN. Transcriptomic analysis of monocytes from SLE-LN(+) vs SLE-LN(-) identified 271 genes differentially expressed, mainly involved in inflammation and IFN-signaling. Levels of IFN-related genes correlated with those of SMC in SLE-LN(+). These results were validated in two external SLE-LN(+) datasets of whole-blood and kidney biopsies. In vitro, SLE-LN(+)-serum promoted a concomitant dysregulation of both, the IFN signature and several SMC, further reversed by JAKinibs treatment. Interestingly, IFNs, key inflammatory cytokines in SLE pathology, also altered SMC. Lastly, the over/down-expression of selected SMC in SLE-monocytes reduced the release of inflammatory cytokines and their adhesion capacity. CONCLUSION: Overall, we have identified, for the first time, a specific alteration of SMC in leukocytes from APS, SLE and APS + SLE patients that would be responsible for the development of distinctive clinical profiles.

TIGIT-Fc fusion protein alleviates murine lupus nephritis through the regulation of SPI-B-PAX5-XBP1 axis-mediated B-cell differentiation.

OBJECTIVES: T cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif (ITIM) domain (TIGIT) is a newly discovered immune checkpoint (IC) that exhibits immunosuppressive function in the regulation of immune system. Activation of TIGIT signaling has emerged as a promising approach for autoimmune disease immunotherapy, such as systemic lupus erythematosus (SLE). METHODS: We generated a chimeric protein, TIGIT-immunoglobulin (Ig), by fusing the extracellular domain of murine TIGIT to the Fc region of mouse IgG2a, which was used to investigated the effect of activating the TIGIT signaling in murine lupus models (MRL/lpr and chronic graft-versus-host disease mice). Treated mice were harvested, and samples of serum, kidney, and spleen were collected for outcome evaluation. In vitro treatment of TIGIT-Ig in B cells was used for exploring the roles of TIGIT in toll-like receptor 7 (TLR7)-mediated B cell differentiation and antibody production. RESULTS: TIGIT-Ig treatment delayed disease progression in both lupus models, accompanied by a decrease in the production of anti-double stranded DNA antibodies (anti-dsDNA), proteinuria, proteinuria/creatinine, and Ig kidney deposition. Additionally, the group treated with TIGIT-Ig displayed a decreased proportion of T helper cell (Th)1 cells, T follicular helper (Tfh) cells, and B-cell subsets, including germinal center B cells (GC B), plasmablasts, and plasma cells, compared to the group treated with control IgG. Interestingly, we also observed an increased proportion of Tregs in the spleen of the TIGIT-Ig group. We have discovered a new way in which activating the TIGIT pathway can regulate B-cell differentiation through the SPI-B-PAX5-XBP1 pathway, resulting in a reduction in autoantibodies. CONCLUSION: Together, TIGIT may be a promising IC target for SLE treatment.

Functional evaluation of rare OASL variants by analysis of SLE patient-derived iPSCs.

BACKGROUND: Systemic lupus erythematosus (SLE) is a chronic systemic autoimmune disease characterized by genetic heterogeneity and an interferon (IFN) signature. The overall landscapes of the heritability of SLE remains unclear. OBJECTIVES: To identify and elucidate the biological functions of rare variants underlying SLE, we conducted analyses of patient-derived induced pluripotent stem cells (iPSCs) in combination with genetic analysis. METHODS: Two familial SLE patient- and two healthy donor (HD)-derived iPSCs were established. Type 1 IFN-secreting dendritic cells (DCs) were differentiated from iPSCs. Genetic analyses of SLE-iPSCs, and 117 SLE patients and 107 HDs in the ImmuNexUT database were performed independently. Genome editing of the variants on iPSCs was performed with the CRISPR/Cas9 system. RESULTS: Type 1 IFN secretion was significantly increased in DCs differentiated from SLE-iPSCs compared to HD-iPSCs. Genetic analyses revealed a rare variant in the 2'-5'-Oligoadenylate Synthetase Like (OASL) shared between SLE-iPSCs and another independent SLE patient, and significant accumulation of OASL variants among SLE patients (HD 0.93%, SLE 6.84%, OR 8.387) in the database. Genome editing of mutated OASL 202Q to wild-type 202 R or wild-type OASL 202 R to mutated 202Q resulted in reduced or enhanced Type 1 IFN secretion of DCs. Three other OASL variants (R60W, T261S and A447V) accumulated in SLE patients had also capacities to enhance Type 1 IFN secretion in response to dsRNA. CONCLUSIONS: We established a patient-derived iPSC-based strategy to investigate the linkage of genotype and phenotype in autoimmune diseases. Detailed case-based investigations using patient-derived iPSCs provide information to unveil the heritability of the pathogenesis of autoimmune diseases.

Efficacy and Safety of Belimumab in Patients With Lupus Nephritis: Subgroup Analyses of a Phase 3 Randomized Trial in the East Asian Population.

RATIONALE & OBJECTIVE: Belimumab improved kidney outcomes in patients with active lupus nephritis (LN) in BLISS-LN, leading to its approval in the United States and the European Union. As data on treatment of East Asian patients with LN are limited, we evaluated the efficacy and safety of belimumab in the BLISS-LN East Asian subgroup. STUDY DESIGN: Prespecified subgroup analysis of BLISS-LN, a phase 3, placebo-controlled, randomized 104-week trial. SETTING & PARTICIPANTS: Adults with biopsy-proven, active LN were randomized (1:1) to belimumab or placebo, plus standard therapy. INTERVENTION: Patients were administered intravenous belimumab 10mg/kg, or placebo, plus standard therapy (oral glucocorticoids and either cyclophosphamide for induction followed by azathioprine for maintenance, or mycophenolate mofetil for both induction and maintenance). At the investigator's discretion, 1-3 intravenous pulses of methylprednisolone, 500-1,000mg each, could be administered during induction. OUTCOMES: The primary end point was primary efficacy renal response (PERR; ie, urinary protein-creatinine ratio≤0.7g/g, estimated glomerular filtration rate no more than 20% below preflare value or≥60mL/min/1.73m2, and no treatment failure) at week 104. Key secondary end points included complete renal response (CRR; urinary protein-creatinine ratio<0.5g/g, estimated glomerular filtration rate no more than 10% below preflare value or≥90mL/min/1.73m2, and no treatment failure) at week 104; PERR at week 52; time to kidney-related event or death; and safety. ANALYTICAL APPROACH: PERR and CRR were analyzed using a logistic regression model, and time to a kidney-related event or death was analyzed using a Cox proportional hazards regression model. RESULTS: 142 patients from mainland China, Hong Kong, South Korea, and Taiwan were included (belimumab, n=74; placebo, n=68). At week 104, more belimumab than placebo patients achieved PERR (53% vs 37%; OR, 1.76 [95% CI, 0.88-3.51]) and CRR (35% vs 25%; OR, 1.73 [95% CI, 0.80-3.74]). At week 52, more belimumab than placebo patients achieved PERR (62% vs 37%; OR, 2.74 [95% CI, 1.33-5.64]). Belimumab reduced the risk of a kidney-related event or death compared with placebo at any time (HR, 0.37 [95% CI, 0.15-0.91]). Safety was similar across treatment groups. LIMITATIONS: Small sample size and lack of formal significance testing. CONCLUSIONS: Safety and efficacy profiles were consistent with BLISS-LN overall population, supporting benefits of belimumab treatment in the East Asian subgroup with LN. FUNDING: This study was funded by GSK (GSK study no. BEL114054). TRIAL REGISTRATION: Registered at ClinicalTrials.gov with study number NCT01639339.

Mendelian randomization analysis suggests no associations of herpes simplex virus infections with systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) characterized by immune dysfunction is possibly more vulnerable to herpes simplex virus (HSV) infection. The infection has been intensively considered a common onset and exacerbation of SLE. This study is aimed at elucidating the causal association between SLE and HSV. A bidirectional two-sample Mendelian Randomization (TSMR) analysis was systematically conducted to explore the causal effect of SLE and HSV on each other. The causality was estimated by inverse variance weighted (IVW), MR-Egger and weighted median methods based on the summary-level genome-wide association studies (GWAS) data from a publicly available database. Genetically proxied HSV infection exhibited no causal association with SLE in the forward MR analysis using IVW method (odds ratio [OR] = 0.987; 95% confidence interval [CI]: 0.891-1.093; p = 0.798), nor did HSV-1 IgG (OR = 1.241; 95% CI: 0.874-1.762; p = 0.227) and HSV-2 IgG (OR = 0.934; 95% CI: 0.821-1.062; p = 0.297). Similar null results with HSV infection (OR = 1.021; 95% CI: 0.986-1.057; p = 0.245), HSV-1 IgG (OR = 1.003; 95% CI: 0.982-1.024; p = 0.788) and HSV-2 IgG (OR = 1.034; 95% CI: 0.991-1.080; p = 0.121) were observed in the reverse MR where SLE served as the exposure. Our study demonstrated no causal association between the genetically predicted HSV and SLE.

Sirtuin 1 overexpression contributes to the expansion of follicular helper T cells in Systemic lupus erythematosus and serves as an easy-to-intervene therapeutic target.

OBJECTIVE: SIRT1, an NAD+-dependent deacetylase, is up-regulated in CD4+ T cells from SLE patients and MRL/lpr lupus-like mice. This study aimed to explore the role of SIRT1 in Tfh cell expansion and its potential value as a therapeutic target for SLE. METHODS: Frequencies of CD4+CXCR5+PD-1+ Tfh cells in peripheral blood from SLE patients and their expression of SIRT1 and BCL-6 were determined with flow cytometry. Naïve CD4+ T cells were transfected with SIRT1-expressing lentivirus and small interfering RNA (siRNA) targeting SIRT1, respectively, and then cultured in a Tfh-polarizing condition to study the impact of SIRT1 on Tfh cell differentiation. This impact was also evaluated in both CD4+ T cells and naïve CD4+ T cells by treatment with SIRT1 inhibitors (EX527 and nicotinamide) in vitro. MRL/lpr mice and pristane-induced lupus mice were treated with continuous daily intake of nicotinamide, and their lupus phenotypes including skin rash, arthritis, proteinuria and serum anti-dsDNA autoantibodies were compared with controls. RESULTS: Expression of SIRT1 was elevated in Tfh cells from SLE patients and positively correlated with Tfh cell frequencies. SIRT1 expression gradually increased during Tfh cell differentiation. Overexpression of SIRT1 by lentiviral vectors significantly promoted Tfh cell differentiation/proliferation. Reciprocally, suppressing expression of SIRT1 by siRNA and inhibiting SIRT1 activity by EX-527 or nicotinamide hindered Tfh cell expansion. Continuous daily intake of nicotinamide alleviated lupus-like phenotypes and decreased serum CXCL13 in the two mouse models. CONCLUSION: SIRT1 overexpression contributes to the expansion of Tfh cells in SLE and may serve as a potential target for treatment.

Hemophagocytic lymphohistiocytosis secondary to virus infection and followed by lupus nephritis recurrence in a renal transplantation pediatric recipient: a case report.

BACKGROUND: Hemophagocytic lymphohistiocytosis (HLH) is a rare and life-threatening disorder characterized by systemic inflammation and organ failure as a result of dysregulated immune cell activation. HLH can be induced by a variety of factors including infection, tumours and autoimmune disease and can also occur in patients following solid organ transplantation. Occurrence of HLH and lupus nephritis (LN) successively within a short period of time after renal transplantation is uncommon. CASE PRESENTATION: We described an 11-year-old female post-transplant patient who presented with hemocytopenia, fever, elevated serum ferritin, splenomegaly, hyperlipidemia, and hypofibrinemia, and was clinically diagnosed with HLH. After comprehensive treatment with corticosteroids, intravenous immunoglobulin (IVIG), and reducing immunosuppressants, her condition improved, but then hematuria ensued. The transplant kidney biopsy showed LN. She was treated with hydroxychloroquine and methylprednisolone while intensive immunosuppressive agents were given. She has remained in remission for two years until now. CONCLUSIONS: The main inducing factors of HLH should be identified as early as possible, and accurate treatment plans should be taken. The long-course IVIG regimen may be one of the effective treatments for virus-induced HLH. After remission of HLH, we need to be alert to the recurrence of autoimmune diseases in patients with underlying diseases, and timely increase immunosuppressants.