Aberrant B-Cell Activation in Systemic Lupus Erythematosus.

Background: B lymphocytes (B cells) are essential in humoral response, and their activation is an important first step for the production of antibodies. However, aberrant B-cell activation is common in the development and progression of autoimmune diseases including systemic lupus erythematosus (SLE), which is characterized by the generation of superfluous autoantibodies. SLE exhibits clinical manifestation such as excessive inflammation and tissue damage. This review aims to summarize the recent emerging studies on aberrant B-cell activation and the associated concurrent therapeutic targets in SLE. Summary: Aberrant B-cell activation is closely associated with the pathogenesis of SLE. Among a variety of mechanisms, dysregulations of B-cell receptor (BCR), toll-like receptor (TLR), and B-cell activating factor receptor (BAFF-R) pathways are the common and dominating factors involved in aberrant B-cell activation. These aberrant signaling transductions play diverse and integrated roles in the development and the pathogenesis of SLE. Therapies targeting aberrant B-cell activation have shown promising efficacy in achieving the clinical alleviation of SLE, suggesting the discovery of new drug targets from these aberrant signaling pathways is imminent. Here, an integrated survey or review of published high-throughput sequencing database covering RNAs of B cells from SLE versus criteria-matched healthy controls highlights that reported signaling molecules in BCR pathway (VAV2, PLC-γ2), TLR pathway (TLR9, P105, IRF7, TAB1), and BAFF-R pathway (SDF-1α) are attitudinally upregulated in SLE patients. This review thus suggests the concurrent and future therapeutic targets and potential biomarkers in both basic and clinical studies of SLE. Key Messages: This review focuses on core B-cell signaling pathways, discussing the progress in the role of aberrant B-cell activation during the pathogenesis of SLE. This review also highlights the signaling molecules from published studies and database for the possible prevention and treatment targets serving the future clinical treatments of SLE.

Effect of sustained intensive therapy with disease modifying anti-rheumatic drugs in rheumatoid arthritis: a 5-year real-world consecutive study.

BACKGROUND: Intensive therapy with disease modifying anti-rheumatic drugs (DMARDs) has been reported to improve the outcomes of rheumatoid arthritis (RA). However, real-world study on the effect of intensive therapy on RA sustained remission is still lacking. This study aimed to investigate the outcome of sustained intensive DMARD therapy (SUIT) for RA in a real-world 5-year consecutive cohort. METHODS: Based on a consecutive cohort of 610 out-patients with RA, remission of RA was assessed in 541 patients from 2012 to 2017, by dividing into SUIT, non-SUIT, and intermittent SUIT (Int-SUIT) groups. Changes in the disease activity scores were evaluated by 28-joint disease activity score based on erythrocyte sedimentation rate (DAS28-ESR), 28-joint disease activity score based on C-reactive protein (DAS28-CRP), and clinical deep remission criteria (CliDR). Cumulative remission rates between different groups were compared using Kaplan-Meier curves and predictive factors of sustained remission were identified by univariate and multivariate logistic regression analysis. RESULTS: The remission rates of the SUIT group decreased from 12.0% (65/541) to 5.6% (20/359) based on DAS28-ESR, from 14.0% (76/541) to 7.2% (26/359) based on DAS28-CRP, and from 8.5% (46/541) to 3.1% (11/359) based on CliDR, respectively, with a gradually decreasing trend during the 5 years. The SUIT regimen led to a significantly higher cumulative remission rate than non-SUIT regimen based on DAS28-ESR (39.7% vs. 19.5%, P = 0.001), DAS28-CRP (42.0% vs. 19.6%, P = 0.001), and CliDR (24.5% vs. 8.7%, P = 0.001). The cumulative remission rates of patients treated with SUIT regimen were significantly higher than those treated with Int-SUIT regimen based on DAS28-ESR (39.7% vs. 25.7%, P = 0.043) and CliDR (24.5% vs. 14.2%, P = 0.047), but there was no significant difference between the two groups based on DAS28-CRP (42.0% vs. 27.4%, P = 0.066). Multivariate logistic regression analysis showed that the use of SUIT regimen was an independent favorable predictor according to different remission definitions (for DAS28-ESR: odds ratio [OR], 2.215, 95% confidence interval [CI]: 1.271-3.861, P = 0.005; for DAS28-CRP: OR, 1.520, 95% CI: 1.345-1.783, P = 0.002; for CliDR: OR, 1.525, 95% CI: 1.314-1.875, P = 0.013). CONCLUSION: Sustained intensive treatment of RA is an optimal strategy in daily practice and will lead to an increased remission rate.

Double Negative B Cell Is Associated With Renal Impairment in Systemic Lupus Erythematosus and Acts as a Marker for Nephritis Remission.

Objective: Recent studies on double negative B cells (DN B cells) suggested that they have potential pathogenic roles in systemic lupus erythematosus (SLE). This study aimed to determine the circulating DN B cells in SLE patients and analyzed the clinical significance of this cell subset. Methods: Fifty-seven SLE patients and fifty healthy controls (HCs) were recruited in this study. Among the 57 SLE patients, 25 had lupus nephritis (LN). All patients were followed up for 24 weeks. Peripheral B cell subsets were analyzed by flow cytometry. Results: DN B cells were significantly elevated in the SLE patients, especially in the patients with LN (p < 0.01). DN B showed a positive correlation with 24-h urine protein excretion (24 h-UPE) levels (r = 0.444, p = 0.034) in LN patients, and inversely correlated with evaluated glomerular filtration rate (eGFR) (r = -0.351, p = 0.011). DN B cells had a positive correlation with plasma cells (r = 0.484, p < 0.001) and memory B cells (r = 0.703, p < 0.001). After treatment, decreased DN B cells were associated with LN alleviation (p = 0.002). In the follow-up, the remission rate of LN patients with decreased DN B cells was significantly higher than LN patients with increased DN B cells (83.33 vs. 25.00%, p = 0.030) at week 24. Conclusions: This study suggests that the peripheral DN B cells are positively correlated with the severity of renal damage in LN patients and may potentially be used as a prognostic marker in LN.

Efficacy and safety of low-dose IL-2 in the treatment of systemic lupus erythematosus: a randomised, double-blind, placebo-controlled trial.

OBJECTIVES: Open-labelled clinical trials suggested that low-dose IL-2 might be effective in treatment of systemic lupus erythematosus (SLE). A double-blind and placebo-controlled trial is required to formally evaluate the safety and efficacy of low-dose IL-2 therapy. METHODS: A randomised, double-blind and placebo-controlled clinical trial was designed to treat 60 patients with active SLE. These patients received either IL-2 (n=30) or placebo (n=30) with standard treatment for 12 weeks, and were followed up for additional 12 weeks. IL-2 at a dose of 1 million IU or placebo was administered subcutaneously every other day for 2 weeks and followed by a 2-week break as one treatment cycle. The primary endpoint was the SLE Responder Index-4 (SRI-4) at week 12. The secondary endpoints were other clinical responses, safety and dynamics of immune cell subsets. RESULTS: At week 12, the SRI-4 response rates were 55.17% and 30.00% for IL-2 and placebo, respectively (p=0.052). At week 24, the SRI-4 response rate of IL-2 group was 65.52%, compared with 36.67% of the placebo group (p=0.027). The primary endpoint was not met at week 12. Low-dose IL-2 treatment resulted in 53.85% (7/13) complete remission in patients with lupus nephritis, compared with 16.67% (2/12) in the placebo group (p=0.036). No serious infection was observed in the IL-2 group, but two in placebo group. Besides expansion of regulatory T cells, low-dose IL-2 may also sustain cellular immunity with enhanced natural killer cells. CONCLUSIONS: Low-dose IL-2 might be effective and tolerated in treatment of SLE. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registries (NCT02465580 and NCT02932137).