Increased levels of anti-dsDNA antibodies in immune complexes before treatment with belimumab associate with clinical response in patients with systemic lupus erythematosus

Glucocorticoid-free remission in patients with SLE in the era of biologics: Immune complex disease is likely to benefit from current medications

OBJECTIVES

In addition to various immunosuppressive agents, belimumab and anifrolumab became available in Japan. We aimed to investigate glucocorticoid-free clinical remission in a single-centre retrospective cohort in October 2023.

METHODS

Our cohort included patients with SLE who needed to start or increase glucocorticoids for disease activity and were followed up for more than 1 year. We investigated the rate of achievement of clinical remission off corticosteroids (CR off C), defined as no clinical score on the SLEDAI-2K without glucocorticoids, baseline predictors of CR off C, medications used when CR off C was achieved, and flare rates following CR off C.

RESULTS

Out of the 60 patients followed for an average of 5.4 (±2.6) years, 17 (28.3%) achieved CR off C in 3.6 (±1.2) years after enrolment. Use of belimumab and anifrolumab accounted for eight (47.1%) of the achievers. Among the baseline data, male sex, recent enrolment, high glucocorticoid dose, and detection of immune complex (IC) significantly predicted CR off C, while lupus nephritis (LN) and a low C3 level tended to predict it. In the multivariate analysis, IC detection was the only predictor of CR off C. Clinical flares were observed in 5.9% of the achievers during a median 1.2 years after achievement of CR off C.

CONCLUSION

In the era of biologics, CR off C was achieved in 28.3% of the patient cohort requiring the start or increase of glucocorticoids for disease activity, with a relatively low rate of flares, suggesting that glucocorticoid-free clinical remission is an achievable target in SLE. IC disease, represented by male sex or nephritis, is likely to benefit from currently available medications.

Anti-Ro52 positivity is associated with progressive interstitial lung disease in systemic sclerosis-an exploratory study

BACKGROUND

Interstitial lung disease (ILD) is the most common cause of death in patients with systemic sclerosis (SSc). Prognostic biomarkers are needed to identify SSc-ILD patients at risk for progressive pulmonary fibrosis. This study investigates autoantibodies measured in bronchoalveolar lavage (BAL) fluid and in serum in reference to the clinical disease course of SSc-ILD.

METHODS

Fifteen patients with new onset SSc-ILD underwent bronchoscopy. Autoantibody levels were analyzed using addressable laser bead immunoassay from BAL fluid and the serum. In a separate longitudinal cohort of 43 patients with early SSc-ILD, autoantibodies in serum were measured at baseline and pulmonary function tests were performed at least 2 times over the course of at least 2 or more years. Linear mixed effect models were created to investigate the relationship between specific autoantibodies and progression of SSc-ILD. Finally, lung tissue from healthy controls and from subjects with SSc was analyzed for the presence of the Ro52 antigen using immunohistochemistry.

RESULTS

Among SSc-ILD patients who were positive for anti-Ro52 (N = 5), 3 (60%) had enrichment of anti-Ro52 in BAL fluid at a ratio exceeding 50x. In the longitudinal cohort, 10/43 patients (23%) were anti-Ro52 positive and 16/43 (37%) were anti-scl-70 positive. Presence of anti-Scl-70 was associated with a lower vital capacity (VC) at baseline (-12.6% predicted VC [%pVC]; 95%CI: -25.0, -0.29; p = 0.045), but was not significantly associated with loss of lung function over time (-1.07%pVC/year; 95%CI: -2.86, 0.71; p = 0.230). The presence of anti-Ro52 was significantly associated with the loss of lung function over time (-2.41%pVC/year; 95% CI: -4.28, -0.54; p = 0.013). Rate of loss of lung function increased linearly with increasing anti-Ro52 antibody levels (-0.03%pVC per arbitrary units/mL and year; 95%CI: -0.05, -0.02; p < 0.001). Immunohistochemical staining localized the Ro52 antigen to alveolar M2 macrophages in peripheral lung tissue both in subjects with and without SSc.

CONCLUSIONS

This study suggests that antibodies targeting Ro52 are enriched in the lungs of patients with new-onset SSc-ILD, linking Ro52 autoimmunity to the pulmonary pathology of SSc. Clinical and immunohistochemical data corroborates these findings and suggest that anti-Ro52 may serve as a potential biomarker of progressive SSc-ILD.

Limited Association between Antibodies to Oxidized Low-Density Lipoprotein and Vascular Affection in Patients with Established Systemic Lupus Erythematosus

Patients with systemic lupus erythematosus (SLE) are at an increased risk of cardiovascular disease. We aimed to evaluate whether antibodies to oxidized low-density lipoprotein (anti-oxLDL) were associated with subclinical atherosclerosis in patients with different SLE phenotypes (lupus nephritis, antiphospholipid syndrome, and skin and joint involvement). Anti-oxLDL was measured by enzyme-linked immunosorbent assay in 60 patients with SLE, 60 healthy controls (HCs) and 30 subjects with anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV). Intima-media thickness (IMT) assessment of vessel walls and plaque occurrence were recorded using high-frequency ultrasound. In the SLE cohort, anti-oxLDL was again assessed in 57 of the 60 individuals approximately 3 years later. The levels of anti-oxLDL in the SLE group (median 5829 U/mL) were not significantly different from those in the HCs group (median 4568 U/mL), while patients with AAV showed significantly higher levels (median 7817 U/mL). The levels did not differ between the SLE subgroups. A significant correlation was found with IMT in the common femoral artery in the SLE cohort, but no association with plaque occurrence was observed. The levels of anti-oxLDL antibodies in the SLE group were significantly higher at inclusion compared to 3 years later (median 5707 versus 1503 U/mL, p < 0.0001). Overall, we found no convincing support for strong associations between vascular affection and anti-oxLDL antibodies in SLE.

B cells in systemic lupus erythematosus: Targets of new therapies and surveillance tools

B cell hyperactivity is a hallmark of the complex autoimmune disease systemic lupus erythematosus (SLE), which has justified drug development focusing on B cell altering agents during the last decades, as well as the off-label use of B cell targeting biologics. About a decade ago, the anti-B cell activating factor (BAFF) belimumab was the first biological agent to be licensed for the treatment of adult patients with active yet non-renal and non-neuropsychiatric SLE, to later be expanded to include treatment of pediatric SLE and, recently, lupus nephritis. B cell depletion is recommended as an off-label option in refractory cases, with the anti-CD20 rituximab having been the most used B cell depleting agent to date while agents with a slightly different binding specificity to CD20 such as obinutuzumab have also shown promise, forming a part of the current pipeline. In addition, terminally differentiated B cells have also been the targets of experimental therapies, with the proteasome inhibitor bortezomib being one example. Apart from being promising drug targets, B and plasma cells have also shown promise in the surveillance of patients with SLE, especially for monitoring B cell depleting or B cell altering therapies. Inadequate B cell depletion may signify poor expected clinical response to rituximab, for example, while prominent reductions in certain B cell subsets may signify a protection against flare development in patients treated with belimumab. Toward an era with a richer therapeutic armamentarium in SLE, including to a large extent B cell altering treatments, the challenge that emerges is to determine diagnostic means for evidence-based therapeutic decision-making, that uses clinical information, serological markers, and gene expression patterns to guide individualized precision strategies.

Predictors of improvement in disease activity in first hospitalized patients with systemic lupus erythematosus: a multicenter retrospective study of a Chinese cohort

Objectives

To analyze the relative factors of improvement in disease activity (IDA) after first hospitalized treatment based on the systemic lupus erythematosus disease activity index (SLEDAI).

Methods

A total of 1069 adult systemic lupus erythematosus (SLE) patients who were hospitalized for the first time in 26 hospitals in Jiangsu Province from 1999 to 2009 were retrospectively analyzed. SLEDAI decrease ≥ 4 during hospitalization was identified as IDA. Relative factors of IDA were assessed by univariate and multivariate logistic regression.

Results

A total of 783 (73.2%) adult SLE patients showed IDA after the first hospitalization, while the remaining patients (n = 286) were in the non-IDA group. The IDA group had higher SLEDAI at admission; fewer patients had SLICC/ACR damage index (SDI) ≥ 1, comorbidities at admission, especially Sjögren’s syndrome, abnormal serum creatinine, and glomerular filtration rate. More patients had mucocutaneous and musculoskeletal involvements, leukopenia, increased C-reactive protein, anti-dsDNA antibody positive, and hypocomplementemia at admission and were treated with methotrexate and leflunomide during hospitalization. After multivariate logistic regression analysis, SDI ≥ 1 (P = 0.005) and combined with Sjögren’s syndrome (P < 0.001) at admission had negative association with IDA. Musculoskeletal involvement (P < 0.001), anti-dsDNA antibody positive (P = 0.012), hypocomplementemia (P = 0.001), and use of leflunomide (P = 0.030) were significantly related with IDA.

Conclusion

Organ damage or comorbidities at admission were adverse to SLE improvement. Anti-dsDNA antibody positive, hypocomplementemia, musculoskeletal involvements, and leflunomide treatment had positive association with IDA of SLE.

Key Points • Organ damage or comorbidities at admission were negatively correlated with SLE improvement. • Anti-dsDNA antibody positivity, hypocomplementemia, musculoskeletal involvements, and leflunomide treatment were positively associated with SLE improvement.

The Role of Belimumab in Systemic Lupus Erythematosis: A Systematic Review

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease involving multiple systems with a range of clinical presentations caused by the production of antibodies, activation of complements, and deposition of immune complexes. The exact cause of SLE is still unknown. The effectiveness of traditional treatment methods for SLE is very little. Nowadays, resistance to conventional therapy, steroids, and immunosuppressants is common among SLE patients. Patients with refractory disease and nephritis generally have severe drug-induced toxicity which contributes to organ dysfunction, despite available therapies. Different biologic agents and therapeutic antibodies have become an alternative and have been under experiment in clinical trials, enrolling patients whose disease is inadequately controlled by conventional treatment. Belimumab is the only targeted therapy approved for SLE treatment. This systematic review discusses one such biological agent for treating systemic lupus erythematosus, namely, belimumab. The systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies included randomized clinical trials (RCTs) from 2005 to 2021 on adult SLE. patients treated with monoclonal antibodies to assess the efficacy and safety. Methodological quality was assessed using PubMed, PMC, the Cochrane Risk of Bias tool, and the QUality In Prognosis Studies Tool (QUIPS) for RCTs. Two independent reviewers performed an electronic search on MEDLINE, Cochrane Library, SCIELO, Scopus, and ResearchGate. Based on a systematic review of articles we found that belimumab appears to be efficacious and generally well-tolerated in the treatment of SLE as compared to other drugs. The long-term use of belimumab combined with standard therapy showed a low incidence of organ damage. A lower incidence of organ damage was seen after initiating treatment in patients with a high risk for organ dysfunction. Patients who test for antinuclear antibody or anti-dsDNA-positive SLE, with moderate symptoms in the skin and musculoskeletal systems despite immunosuppressants, are treated with belimumab as an adjunct therapy. Patients with severe lupus nephritis or active CNS lupus cannot be treated with belimumab. Belimumab is effective in most races, as a clinical trial done in North-East Asia showed improvement in SLE symptoms and decreased dependence on prednisone. Belimumab also decreased disease activity and severe flares. Belimumab had greater efficacy in children.

Early Changes in B and Plasma Cell Subsets and Traditional Serological Markers as Predictors of SRI-4 Response to Therapy in Systemic Lupus Erythematosus

Objective

With the premise of the hypothesis that early biological responses to therapy for active systemic lupus erythematosus (SLE) portend later clinical improvements, we studied changes in B cell subsets and traditional serological markers in relation to clinical response to standard therapy (ST) with or without the addition of belimumab.

Patients and Methods

We analyzed data from the BLISS-76, BLISS-SC, and BLISS Northeast Asia trials (N = 1712). Circulating CD19⁺ B cell subsets were determined by flow-cytometry. We studied associations of relative to baseline percentage changes in circulating B and plasma cell subsets, anti-dsDNA antibody levels and complement levels with SLE Responder Index (SRI)-4 response after 52 weeks of treatment. Changes occurring through week 8 were deemed "rapid," through week 24 "early," and thereafter "delayed".

Results

In the analysis of the entire cohort, SRI-4 responders showed more prominent decreases from baseline through week 52 in CD19⁺CD20⁺CD27^- naïve B cells (median change: -61.2% versus -50.0%; P = 0.004), CD19⁺CD20^-CD27 ^bright plasmablasts (-44.9% versus -33.3%; P = 0.011), and CD19⁺CD20^-CD138⁺ long-lived plasma cells (-48.2% versus -37.1%; P = 0.024), and a more prominent rapid (+92.0% versus +66.7%; P = 0.002) and early (+60.0% versus +49.5%; P = 0.033) expansion of CD19⁺CD20⁺CD27⁺ memory B cells than non-responders. More prominent rapid reductions in anti-dsDNA (-14.8% versus -8.7%; P = 0.043) and increases in C3 (+4.9% versus +2.1%; P = 0.014) and C4 levels (+11.5% versus +8.3%; P = 0.017) were documented in SRI-4 responders compared with non-responders among patients who received add-on belimumab, but not among patients who received non-biological ST alone.

Conclusion

SRI-4 responders showed a more prominent rapid expansion of memory B cells and more prominent delayed reductions in naïve B cells, plasmablasts and long-lived plasma cells. Moreover, clinical response to belimumab was associated with preceding more prominent reductions of anti-dsDNA and increases in C3 and C4 levels. Monitoring biological changes may prove useful in SLE patient surveillance and early treatment evaluation.

Diagnostic, predictive and prognostic biomarkers in systemic lupus erythematosus: current insights

PURPOSE OF REVIEW

Biomarkers for diagnosis, monitoring and prognosis still constitute an unmet need for systemic lupus erythematosus (SLE). Focusing on recent findings, this review summarises the current landscape of biomarkers in lupus.

RECENT FINDINGS

Urine activated leukocyte cell adhesion molecule (ALCAM) exhibited good diagnostic ability in SLE and lupus nephritis (LN) whereas cerebrospinal fluid neutrophil gelatinase-associated lipocalin (NGAL) showed promise in neuropsychiatric SLE. Urine ALCAM, CD163 and vascular cell adhesion molecule 1 (VCAM-1) may be useful in surveillance of LN. Urine monocyte chemoattractant protein 1 was found to predict treatment response in SLE, and urine CD163 and NGAL treatment response in LN. Serum complement component 3 (C3) and urinary VCAM-1 have been reported to portend long-term renal prognosis in LN.

SUMMARY

NGAL holds promise as a versatile biomarker in SLE whereas urine ALCAM, CD163 and VCAM-1 displayed good performance as biomarkers in LN. The overall lack of concerted corroboration of leading candidates across multiple cohorts and diverse populations leaves the current biomarker landscape in SLE in an urgent need for further survey and systematic validation.

3-hydroxy butyrate dehydrogenase 2 deficiency aggravates systemic lupus erythematosus progression in a mouse model by promoting CD40 ligand demethylation

The implications of the CD40-CD40 ligand (CD40L) signaling pathway in systemic lupus erythematosus (SLE) were well documented, due to its important role among immune cells. Previous research found that 3-hydroxy butyrate dehydrogenase 2 (BDH2), a modulator of intracellular iron homeostasis and iron transportation promoted the pathogenic process of SLE by regulating the demethylation of cd70, cd11a, and cd40l genes among CD4 + T cells. The purpose of this study was to explore the role of BDH2 in oxidative damage-induced SLE. First, CD4 + T cells treated with H₂O₂ were injected into the tail vein of mice to establish a lupus model. CD40L knockdown significantly decreased CD40L expression on CD4 + T cells in the spleen of SLE mice. Compared with SLE model mice, the levels of serum anti-dsDNA antibody and urinary protein in the CD40L interference group were significantly decreased. CD40L knockdown alleviated the immune complex glomerulonephritis in syngeneic SLE mice. Moreover, the levels of IFN-γ and IL-2 were decreased. However, IL-4 and IL-10 levels were significantly upregulated in the serum of CD40L knockdown SLE mice, compared with SLE model mice. Accordingly, CD40L knockdown reduced Th1/Th2 percentage in SLE mice. Inhibiting the expression of BDH2 of CD4 + T cells promoted the demethylation of CD40L, while it inhibited cell proliferation, elevated oxidative stress through increased expression of CD40L, and thus, promoted the progress of SLE. Our results demonstrate that BDH2 aggravates the pathologic progression of SLE in mice, by increasing the demethylation level of CD40L among CD4 + T cells.

Predictive factors for concomitant pulmonary arterial hypertension at diagnosis of systemic lupus erythematosus in a Chinese population

AIM

To investigate the predictive factors of pulmonary arterial hypertension (PAH) in systemic lupus erythematosus (SLE) patients.

METHOD

This chart review study included 408 SLE patients. We defined PAH as 2 consecutive systolic pulmonary arterial pressure (PAP) values ≥40 mm Hg by echocardiography. Demographic characteristics, clinical symptoms, autoantibodies, and laboratory tests were studied.

RESULTS

Thirty-four patients in the SLE/PAH+ group and 374 patients in the SLE/PAH- group were analyzed. The prevalence of PAH in SLE is 8.3% in this study. The occurrences of interstitial pneumonitis, polyserositis and myocardial damage were higher in the SLE/PAH+ group (P = .001, P = .033 and P < .001, respectively). The occurrence of anti-double-stranded DNA and anti-ribosomal RNA protein (anti-rRNP) antibodies were lower in the SLE/PAH+ group (P = .003, .010). Positive rates of anti-Sjögren's syndrome antigen A (anti-SSA)/Ro52 antibodies and anti-SSB antibodies were higher in the SLE/PAH+ group (P = .046, .021). C-reactive protein and immunoglobin G (IgG) were higher in the SLE/PAH+ group (P = .009, .005). Ejection fraction and SLE disease activity index between the 2 groups had no differences. Multivariable logistic regression indicated that interstitial pneumonitis, myocardial damage and high IgG are predictive factors for SLE-associated PAH patients.

CONCLUSION

From this study, we found that interstitial pneumonitis, myocardial damage, and high IgG were predictive factors of PAH in SLE patients.

Chronic exposure to PM2.5 aggravates SLE manifestations in lupus-prone mice

Background

Air pollution causes negative impacts on health. Systemic lupus erythematosus (SLE) is an autoimmune disease with diverse clinical manifestations and multifactorial etiology. Recent studies suggest that air pollution can trigger SLE and induce disease activity. However, this association has not been deeply investigated. Thus, the aim of this study was to evaluate whether exposure to fine particulate matter (PM2.5) exacerbates SLE manifestations, focusing on renal complications, in a lupus-prone animal model. Female NZBWF1 mice were exposed daily to 600 μg/m³ of inhaled concentrated ambient particles (CAP) or filtered air (FA). Survival rate, body weight, weight of organs (kidney, spleen, thymus, liver and heart), blood cell count, proteinuria, kidney stereology, renal histopathology, gene expression and oxidative stress were analyzed.

Results

Female NZBW mice exposed to CAP showed decreased survival, increased circulating neutrophils, early onset of proteinuria and increased kidney weight with renal cortex enlargement when compared to NZBW mice exposed to FA.

Conclusions

This work shows that air pollution aggravates some SLE manifestations in lupus-prone mice. These results reinforce the need of reducing air pollutant levels in order to promote a better quality of life for individuals diagnosed with SLE.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12989-021-00407-0.

Accumulation of antinuclear associated antibodies in circulating immune complexes is more prominent in SLE patients from Sudan than Sweden

The role of anti-nuclear autoantibody (ANA) specificities in immune complexes (IC) formation has been studied to a limited extent in SLE, and not at all in African SLE patients. We compared ANA in IC from Sudanese and Swedish SLE patients. We included 93 Sudanese and 332 Swedish SLE patients fulfilling the 1982 ACR criteria. IC were captured using C1q-coated beads. ANA specificities were quantified in sera and IC. Results were related to modified SLEDAI. Whereas serum levels of anti-Sm, anti-dsDNA and anti-ribosomal P were higher in Swedish patients, IC levels of most ANA specificities were higher among Sudanese patients. This difference was especially prominent for anti-chromatin antibodies, which remained after adjustment for age, disease duration and treatment. Total levels of C1q-binding IC correlated with levels of specific ANA in IC, with highest correlations for anti-chromatin antibodies among Sudanese patients. Whereas occurrence of anti- SSA/Ro60, anti-histone and anti-U1RNP in both serum and IC associated with high SLEDAI score, anti-dsDNA in IC but not in serum associated with high SLEDAI. ANA, especially antibodies targeting chromatin, accumulate more in IC from Sudanese SLE patients. If the autoantibody fraction forming IC is pathogenically important, this might explain the generally described severe SLE in black populations.

B Cell Therapy in Systemic Lupus Erythematosus: From Rationale to Clinical Practice

B cell hyperactivity and breach of tolerance constitute hallmarks of systemic lupus erythematosus (SLE). The heterogeneity of disease manifestations and relatively rare prevalence of SLE have posed difficulties in trial design and contributed to a slow pace for drug development. The anti-BAFF monoclonal antibody belimumab is still the sole targeted therapy licensed for SLE, lending credence to the widely accepted notion that B cells play central roles in lupus pathogenesis. However, more therapeutic agents directed toward B cells or B cell-related pathways are used off-label or have been trialed in SLE. The anti-CD20 monoclonal antibody rituximab has been used to treat refractory SLE during the last two decades, and the anti-type I IFN receptor anifrolumab is currently awaiting approval after one phase III clinical trial which met its primary endpoint and one phase III trial which met key secondary endpoints. While the latter does not directly affect the maturation and antibody production activity of B cells, it is expected to affect the contribution of B cells in proinflammatory cytokine excretion. The proteasome inhibitor bortezomib, primarily directed toward the plasma cells, has been used in few severe cases as an escape regimen. Collectively, current clinical experience and primary results of ongoing clinical trials prophesy that B cell therapies of selective targets will have an established place in the future personalized therapeutic management of lupus patients.

Autoantibody and Cytokine Profiles during Treatment with Belimumab in Patients with Systemic Lupus Erythematosus

We investigated whether belimumab treatment impacts on levels of autoantibodies and cytokines of interest in systemic lupus erythematosus (SLE). Longitudinally collected serum samples from 78 belimumab-treated Swedish SLE patients were analysed. Serum cytokine levels were determined using Luminex xMAP technology, and nuclear antigen autoantibody specificities using addressable laser bead immunoassay. In patients with detectable levels at baseline, interferon (IFN)-α2 levels were lower at month 6 (median; interquartile range (IQR): 8.9; 1.5-54.9 pg/mL) versus baseline (28.4; 20.9-100.3 pg/mL; p = 0.043). Interleukin (IL)-6 (baseline: 7.1; 2.9-16.1 pg/mL) decreased from month 6 (0.5; 0.5-6.3 pg/mL; p = 0.018) and throughout a 24 month follow-up. IL-10 (baseline: 12.6; 2.8-29.7 pg/mL) showed more rapid decreases from month 3 (1.8; 0.6-9.1 pg/mL; p = 0.003). Levels of anti-dsDNA (p < 0.001), anti-Smith antigen (Sm) (p = 0.002), anti-U1 small nuclear ribonucleoprotein (U1RNP) (p < 0.001), anti-Sm-U1RNP complex (p = 0.028), and anti-ribosomal P (p = 0.012) antibodies decreased from month 3 and remained decreased. Anti-Sm positivity at baseline was associated with higher probability and/or shorter time to achieve sustained SLE responder index-4 response (hazard ratio (HR): 2.52; 95% CI: 1.20-5.29; p = 0.015), independently of other factors. Decline of IL-6 levels through month 3 was greater in responders. In summary, belimumab treatment lowered IFN-α2, IL-6, and IL-10 levels, as well as levels of multiple autoantibodies, however after different time spans. Notably, anti-Sm positivity and early decline in IL-6 levels were associated with favorable treatment outcome.