anti-dsDNA Antibody Levels Research Articles

Anti-complement factor H (CFH) autoantibodies could delay pristane-induced lupus nephritis

PurposeAnti-complement factor H (CFH) autoantibodies could be detected in lupus and its significance remained to be elucidated. Herein, we aimed to explore the roles of anti-CFH autoantibodies based on pristane-induced lupus mice.MethodsTwenty-four female Balb/c mice were randomly divided into four groups, with one group injected with pristane (pristane group), one group with pristane and then human CFH (hCFH) (pristane-CFH group) 3 times, and the other two as vertical controls, PBS group and PBS-CFH group. Histopathological analysis was performed six months after pristane administration. Levels of hCFH, anti-CFH autoantibodies and anti-dsDNA antibody were detected. Murine IgG (mIgG) were purified and cross-reactivity, epitopes, subclasses and functional analysis were further evaluated in vitro.ResultsImmunization with hCFH and subsequent development of anti-CFH autoantibodies significantly attenuated nephritis of pristane-induced lupus, including lower levels of urinary protein and serum creatinine, decreased levels of serum anti-dsDNA antibody, greatly ameliorated renal histopathologic damage, decreased IgG, complements (C1q, C3) deposits and lower inflammatory factor (IL-6) expression in glomerulus. Furthermore, the purified mIgG (contained anti-CFH autoantibodies) could recognize both hCFH and murine CFH, and the epitopes were predominantly located in hCFH short consensus repeats (SCRs) 1–4, 7 and 11–14. The IgG subclasses were predominant IgG1. The autoantibodies could enhance the binding between hCFH and C3b, and increase factor I mediated-C3b lysis in vitro.ConclusionOur results suggested that anti-CFH autoantibodies could attenuate pristane-induced lupus nephritis by increasing bio-functions of CFH on regulating complement activation and controlling inflammation.

Lupus-like phenotypes emerge from loss of macrophage derived Dnase1L3

Abstract One leading cause of death in women is autoimmunity. One prominent autoimmune disease is Systemic Lupus Erythematosus (lupus). During lupus, inflammation is driven by autoantibodies that target cell-free DNA. Cell-free DNA is degraded by two serum endonucleases, Dnase1 and Dnase1L3. The loss of Dnase1L3 causes lupus in humans and mice, but the amount of Dnase1L3 necessary to prevent lupus onset is unknown. Since DnaselL3 is secreted by macrophages and dendritic cells, we hypothesized that loss of macrophage-derived DnaselL3 is sufficient to cause lupus-like phenotypes in mice. We generated conditional knockout (cKO) mice lacking DnaselL3 expression in macrophages. Sera was collected weekly from these mice until 50 weeks of age. To measure autoantibody induction, total IgG, total IgM, anti-dsDNA and anti-nuclear antibody levels were analyzed at 4, 20, 30 and 50 weeks. Sandwich ELISA was used to quantitate antibody levels in control and cKO mice. Homogeneous and peripheral anti-nuclear antibodies were detected by immunofluorescence, consistent with anti-dsDNA antibodies. Total IgG, anti-ds DNA antibody levels increased in cKO mice. We conclude that SLE-like phenotypes arise in mice due to the loss of macrophage Dnase1L3. This suggest that macrophage derived DnaselL3 is critical to controlling lupus. Plains Bridges to the Baccalaureate Program (PBB) (NIH 2R25GM83730-B)

Phenotypic Evaluation of TREX1 Null Mice as a Model for Lupus-Like Autoimmune Disease

Abstract TREX1 (DNase III) is the major mammalian 3’-5’ DNA exonuclease and thought to play a major role in cell death and genomic DNA degradation. Dysfunction of Trex1 has been suggested to activate immune response by self DNA, as TREX1 null mice develop inflammatory myocarditis similar to autoimmune cardiomyopathy and produce type 1 IFN. TREX1 D18N causes a monogenic cutaneous form of lupus called familial chilblain lupus and exhibits dysfunctioned dsDNA-degrading activity, providing a link between dsDNA degradation and nucleic acid-mediated autoimmune diseases. Using CRISPR-Cas9, we generated a Trex1 −/−mouse by knocking out exon 2 and performed comprehensive phenotypic analyses to evaluate the loss of function of TREX1 and its potential application in SLE research. Both female and male TREX1 null mice showed dramatically increased post-wean morbidity and significantly increased serum ALT, AST and LDH levels, compared to wildtype and heterozygotes from 6 to 24 weeks of age, indicating liver and heart injuries. Pathohistological analysis showed inflammatory immune cell infiltration in liver, heart, spleen, kidney, lung and skin among TREX1 null mice. Serum anti-dsDNA antibody levels were significantly increased and remained high from 7 to 25 weeks of age, consistent with Trex1’s being the major DNA exonuclease. Urine protein to creatinine ratio was dramatically increased at 28 weeks of age among TREX1 null mice. In conclusion, the Trex1 −/−mice we generated in this work showed lupus-like inflammatory autoimmune responses in multiple organs, providing an urgently needed tool to study Trex1-mediated autoimmunity and to evaluate potential therapeutic treatments for lupus.

OA25 Identification of biomarkers to stratify response to combination therapy with belimumab and rituximab in a randomized trial, BEAT-LUPUS for systemic lupus erythematosus

Abstract Background/Aims The BEAT-lupus double-blind randomised trial demonstrated that belimumab (anti-BAFF antibody) reduced the number of severe-flares (compared to placebo) after B-cell depletion (rituximab) in patients with systemic lupus erythematosus (SLE)(1). We longitudinally immune profiled patients recruited to the trial to identify which patients would benefit most from belimumab after rituximab combination therapy. Methods We constructed two models (because the number of patients who provided serum/blood RNA samples and peripheral blood mononuclear cells differed) using baseline data to predict a major clinical response (MCR)(2) to belimumab after rituximab at 52-weeks utilising conventional and machine learning approaches: A) Model 1: serum autoantibodies and cytokines, peripheral blood RNA expression, clinical data, and routinely collected laboratory-markers (10 responders, 11 non-responders). B) Model 2: B-cell flow-cytometry (8 responders, 8 non-responders). The emerging key variables were then used as effect modifiers comparing response to belimumab and placebo after rituximab. Results Baseline serum IgA2 anti-dsDNA antibody levels emerged from model 1 as the key predictor of MCR with an AUROC (area under the curve of the receiver operator characteristic) of 0.81 (95% CI: 0.70-0.96) in predicting an MCR by 52-weeks in the belimumab arm. An optimal cut point of serum IgA2 anti-dsDNA antibody (10.7 AU/arbitrary unit), derived from AUROC, was applied as an effect modifier which improved the delta between response to belimumab vs placebo from 13% (without the effect modifier) to 48% (95% CI: 10-70; p = 0.021) (Belimumab - 64% [9 responders, 5 non-responders], placebo - 16% [2 responders, 10 non-responders]). Belimumab significantly reduced serum IgA2 anti-dsDNA antibody levels compared to placebo at 52-weeks (difference: 20 AU; 95% CI: 13-27; p < 0.001) only in those patients who achieved an MCR, falling by 60% from baseline (difference: 23 AU; 95% CI: 11-35; p < 0.001, compared to non-response). Prediction model 2 identified the frequency of T-bet+CD11c+DNM-2 (double negative memory B-cell, type-2: CD11c+T-bet+CD38-CD27-IgD-CD21-CD24-) as the strongest predictor of MCR by 52-weeks in the belimumab arm with an AUROC of 1.00 (95% CI: 1.00-1.00). Using T-bet+CD11c+DNM-2 as an effect modifier (optimal cut point: 14.2% of total B-cells) the delta improved from 13% to 71% (95% CI: 23-92; p = 0.007) (Belimumab - 100% [8 responders, 0 non-responders], placebo - 29% [2 responders, 5 non-responders]). The frequency of T-bet+CD11c+DNM-2 was significantly lower in the belimumab arm at 52-weeks compared to placebo (difference: 6%; 95% CI: 3-11; p = 0.001), and dropped by 48% from baseline in belimumab responders (difference with non-responders: 11%; 95% CI: 6-15; p < 0.001). Conclusion High baseline serum IgA2 anti-dsDNA antibody and peripheral blood T-bet+CD11c+DNM-2 B-cell frequency could guide patient selection for belimumab after rituximab combination therapy thereby improving outcomes and access to targeted therapies for patients with SLE. Exploration of the underlying mechanisms and confirmation of these results including combining the two prediction models in a larger clinical trial are required. Reference 1. Shipa M, et al. Annals of Internal Medicine. 2021;174:1647-57. 2. McDonald S, et al. Lupus Sci Med. 2022;9:e000584. Disclosure M. Shipa: Grants/research support; Versus arthritis, LUPUS-UK. M. Parvaz: None. D. Nguyen: None. L. Santos: None. D.A. Isenberg: Consultancies; Astra Zeneca, Eli Lilly, Merck Serono, Servier and UCB. C. Gordon: Consultancies; Center for Disease Control and Prevention, AbbVie, Amgen, Astra-Zeneca, EMD Serono, MGP, Sanofi and UCB. M.R. Ehrenstein: Consultancies; GSK. Grants/research support; Versus arthritis.

Risk factors for subsequent lupus nephritis in patients with juvenile-onset systemic lupus erythematosus: a retrospective cohort study

BackgroundLupus nephritis (LN) is a crucial organ involvement in systemic lupus erythematosus (SLE). Patients with LN have higher morbidity and mortality rates than those without. Among all patients with LN, 20–40% had delayed onset, but the data for patients with juvenile-onset SLE (jSLE), who have a higher percentage of LN than patients with adult-onset SLE (aSLE), were limited. This study aimed to determine the risk factors for subsequent LN in patients with jSLE.MethodsA retrospective cohort study was conducted between 2008 and 2018 in a single tertiary medical centre. Patients with diagnosed jSLE were reviewed. We investigated those without LN at diagnosis and whether they developed LN afterward. The primary outcome was the development of subsequent LN. Clinical manifestations at diagnosis, serial laboratory data, and treatments were reviewed during follow-up periods.ResultsAmong the 48 patients with jSLE without initial LN, 20 developed subsequent LN later (Group 1), whereas 28 remained free of LN (Group 2). There was no difference in the percentage of initial manifestations except for more discoid rashes in Group 2 patients. In the Cox regression model, elevated average anti-double-stranded DNA (dsDNA) antibody, low average serum complements, and high average erythrocyte sedimentation rate (ESR) levels during follow-up were predictors of subsequent LN. After adjusting for these factors in multivariable analyses, only high average anti-dsDNA antibody and high average ESR levels remained predictive of subsequent LN. For every 100 IU/ml increase in anti-dsDNA antibody, the risk for subsequent LN in jSLE increases by 1.29 times (hazard ratio = 1.29, 95% confidence interval 1.055–1.573).ConclusionPersistently high anti-dsDNA antibody and ESR levels during the follow-up period were risk factors for subsequent LN in patients with jSLE.

Pristane cadmium chloride nanoemulsion accelerates the onset of systemic lupus erythematosus in a C57BL/6 mouse model.

To accelerate the onset of systemic lupus erythematosus in C57BL/6 mice by injecting cadmium chloride nanoemulsion and shorten the traditional modeling time. Pristane cadmium chloride nanoemulsion was prepared, and 66 C57BL/6 mice were randomly divided into four groups. The pristane group was intraperitoneally injected with 0.6mL of pristane blank nanoemulsion, the model group was injected with 0.6mL of pristane cadmium chloride nanoemulsion, the Cadmium chloride control group was injected with 0.6mL of cadmium chloride nanoemulsion, and the control group was injected with the same amount of 0.9% sodium chloride solution. Urine protein content, anti-dsDNA antibody content, Th1 cell/Th2 cell ratio, and kidney staining were detected in each group. The model group began to develop disease in the 4th week, the anti-dsDNA antibody level reached 566.71 ± 1.44ng/L, and the proteinuria reached 245.38 ± 30.54ng/mL. The model group showed an onset at least 5 weeks earlier than that in the pristane group. There was no significant difference in anti-dsDNA antibody content between Cadmium chloride control group and blank group. At the 12th week, the Th1/Th2 cell ratio in the model group significantly decreased, and the pathological changes in the kidneys were consistent with the typical manifestations of lupus in mouse models. These results suggest that cadmium chloride promotes earlier onset of pristane-induced systemic lupus erythematosus in a C57BL/6 mouse model.

Outcome of rituximab therapy in patients with systemic lupus erythematosus

Purpose: Systemic lupus erythematosus (SLE) is a chronic autoimmune disease affecting multiple organs. Rituximab (RTX) is an anti-CD20 monoclonal antibody that is an approved treatment for various autoimmune diseases. However, no randomized controlled trial (RCT) has proved the benefit of RTX for patients with lupus nephritis (LN). We conducted a retrospective study to evaluate the effectiveness of RTX as an immunosuppressive treatment for SLE and LN. Methods: Subjects were selected by reviewing medical records from January 2004 to July 2020 in the rheumatology departments of two hospitals in Saudi Arabia. Patients were included if they were >16 years of age with a diagnosis of SLE that fulfilled the 2019 European League Against Rheumatism and the American College of Rheumatology criteria and had received RTX for SLE. Clinical and laboratory data, SLE disease activity index (SLEDAI) score and adverse events before and 3, 6, and 12 months after starting RTX were collected. Statistical analysis was conducted comparing median baseline values with those at various times after starting RTX. Results: 40 patients with SLE were included in the study. The indications for RTX were arthritis (37.5%) and LN (32.5%), with LN varying in severity. Over the 12 months from starting RTX, there were significant improvements in SLEDAI score, and anti-dsDNA antibody, C3, and C4 levels (P<0.001, P=0.048, P<0.001, and P=0.005, respectively). Steroid dose was also significantly reduced (P<0.001) post-RTX. Meanwhile, serum creatinine at 6 and 12 months did not differ significantly from the baseline. Proteinuria in patients receiving RTX for LN showed a significant reduction from median baseline value to that at 12 months (P=0.028). Conclusions: RTX effectively controlled multiple manifestations of SLE in a Saudi population and exhibited a steroid-sparing effect in this population. Larger RCTs should be conducted to determine the patients that could benefit from such treatment.

Regulatory effect of IL-38 on NF-κB pathway in systemic lupus erythematosus

BackgroundIL-38 is a newly identified cytokine that exhibits immunosuppression effects. However, there are few studies focusing on the effects and mechanisms of IL-38 in the systemic lupus erythematosus (SLE). AimWe investigated the effects and mechanisms of IL-38 on NF-κB signaling pathway in SLE. MethodsLevels of IL-38, IL-36R, IL-1RAcP, IKKα/β, NF-κB, TNF-α and anti-dsDNA antibody levels in peripheral blood of SLE patients, and in peripheral blood and kidney tissues of MRL/lpr mice, were examined with real-time PCR, ELISA, Western blot and immunohistochemistry. Pathological changes of kidney were detected with PAS staining. Recombinant human IL-38 protein and IL-38 siRNA were used to intervene the PBMCs of SLE patients and MRL/lpr mice. ResultsThe mRNA and protein levels of IL-38 in peripheral blood of SLE patients decreased and were positively correlated. The mRNA and protein levels of IKKα/β, NF-κB, and TNF-α increased, especially in patients with active SLE. There was a negative correlation between IL-38 and the levels of IKKα/β, NF-κB and TNF-α in SLE patients. In vitro experiments showed that the levels of IKKα/β, NF-κB and TNF-α, and anti-dsDNA antibodies decreased in PBMCs of SLE patients after treatment with human recombinant IL-38 protein. These effects were reversed after IL-38 siRNA intervention. Consistent results were obtained on IL-38, IKKα/β, NF-κB, and TNF-α in MRL/lpr lupus mice after treatment with IL-38 protein or IL-38 shRNA. Additionally, kidney function (reflected by creatinine and blood urea nitrogen), anti-dsDNA antibody, complement C3, and urinary protein levels decreased after treatment with IL-38 protein but increased after IL-38 shRNA treatment. PAS staining showed IL-38 protein treatment induced mild hyperplasia of glomerular mesangial cells and a small amount of lymphocyte infiltration. However, these were aggravated after IL-38 shRNA treatment. ConclusionIL-38 may be involved in the occurrence and development of SLE by regulating the NF-κB signaling pathway. This study only discussed the relationship between IL-38 and NF-κB, and more biological functions of IL-38 need to be further studied.

Effects of high fat diet-induced obesity on pathophysiology, immune cells, and therapeutic efficacy in systemic lupus erythematosus

Prior studies have suggested a strong link between obesity and autoimmune diseases. This study aimed to evaluate the effects of high fat diet (HFD)-induced obesity on the disease pathogenesis, immune cell infiltration, and therapeutic efficacy in systemic lupus erythematosus (SLE). Treatment with methylprednisolone significantly increased the survival in the control diet group, but not in the HFD group. An HFD significantly increased the incidence of severe proteinuria and glucose intolerance. Regardless of the diet, treatment with methylprednisolone significantly decreased the serum levels of anti-dsDNA antibodies, IL-2, IL-10, and interferon γ-induced protein 10 (IP-10), and improved the renal pathology scores. Treatment with methylprednisolone significantly lowered the serum levels of IL-6, MCP-1, and TNF-α in the control diet group, but not in the HFD group. HFD significantly increased the proportions of CD45+ and M1 cells and significantly decreased the proportion of M2 cells in white adipose tissue; methylprednisolone treatment significantly rescued this effect. In the HFD group, methylprednisolone treatment significantly decreased the M1:M2 and increased the Foxp3+:RORγt+ cell in the spleen compared with the untreated group. These data improve our understanding of the effect of HFD on the therapeutic efficacy of corticosteroids in SLE treatment, which could have clinical implications.

Comparison of current methods for anti-dsDNA antibody detection and reshaping diagnostic strategies.

Anti-double-stranded DNA antibodies (anti-dsDNA) are considered a specific marker for systemic lupus erythematosus (SLE). Though the Farr technique was once the reference method for their detection, it has been almost entirely replaced by more recently developed assays. However, there is still no solid evidence of the commutability of these methods in terms of diagnostic accuracy and their correlation with the Crithidia luciliae immunofluorescence test (CLIFT). Anti-dsDNA antibody levels were measured in 80 subjects: 24 patients with SLE, 36 disease controls drawn from different autoimmune rheumatic diseases (14 systemic sclerosis, 10 Sjögren's syndrome, nine autoimmune myositis, three mixed connective tissue disease), 10 inflammatory arthritis and 10 apparently healthy blood donors by eight different methods: fluorescence enzyme immunoassay, microdot array, chemiluminescent immunoassay (two assays), multiplex flow immunoassay, particle multi-analyte technology immunoassay and two CLIFT. At the recommended manufacturer cut-off, the sensitivity varied from 67% to 92%, while the specificity ranged from 84% to 98%. Positive agreement among CLIFT and the other assays was higher than negative agreement. Mean agreement among methods assessed by the Cohen's kappa was 0.715, ranging from moderate (0.588) to almost perfect (0.888). Evaluation of the concordance among quantitative values by regression analysis showed a poor correlation index (mean r2, 0.66). The present study shows that current technologies for anti-dsDNA antibody detection are not fully comparable. In particular, their different correlation with CLIFT influences their positioning in the diagnostic algorithm for SLE (either in association or sequentially). Considering the high intermethod variability, harmonization and commutability of anti-dsDNA antibody testing remains an unachieved goal.

Circular RNA expression profile of systemic lupus erythematosus and its clinical significance as a potential novel biomarker

BackgroundCircular RNAs (circRNAs) are a class of endogenous noncoding RNAs that are more abundant, specific, and highly organized than linear RNAs. Increasing evidence supports that circRNAs may serve as diagnostic biomarkers in many diseases, but their potential as biomarkers in systemic lupus erythematosus (SLE) remains unclear.ObjectiveWe investigated the critical circRNAs involved in SLE progression and explored their potential application as biomarkers in SLE.MethodRNA sequencing was conducted on peripheral blood mononuclear cells (PBMCs) from 4 SLE patients and 4 healthy volunteers. CircRNA profile data were analyzed to identify differentially expressed circRNAs and visualized via R software. After screening, qPCR analysis of target circRNA expression was performed using PBMCs from 31 SLE patients and 35 healthy volunteers. Correlations between circRNA expression levels and the SLEDAI score were assessed via Spearman correlation analysis. Finally, the performance of circRNAs as biomarkers in SLE was examined by receiver operating characteristic curve analysis.ResultsThe result identified six differentially expressed circRNAs between SLE patients and healthy controls: hsa_circ_0006689, hsa_circ_0070562, hsa_circ_0006117, hsa_circ_0007683, hsa_circ_0042519, and hsa_circ_0008647. The validation analysis showed differing relative expression levels of hsa_circ_0007683, hsa_circ_0042519, hsa_circ_0008647, and hsa_circ_0006689 between SLE patients and healthy volunteers (P < 0.05), and hsa_circ_0006689 expression in PBMCs correlated with the SLEDAI score (P < 0.05). Furthermore, addition of hsa_circ_0006689 expression increased the sensitivities of anti-dsDNA antibody and anti-Sm antibody levels for SLE diagnosis (from 29.03 to 61.30% and 32.26–71.00%, respectively).ConclusionOur results suggest hsa_circ_0006689 may be a useful circRNA biomarker for SLE diagnosis and prognosis.

Evidence for charge-based mimicry in anti dsDNA antibody generation

Mechanisms for the generation of anti-dsDNA autoantibodies are still not completely elucidated. One theory states that dsDNA interacts for mimicry with antibodies raised versus other antigens but molecular features for mimicry are unknown.Here we show that, at physiological acid-base balance, anti-Annexin A1 binds IgG2 dsDNA in a competitive and dose-dependent way with Annexin A1 and that the competition between the two molecules is null at pH 9. On the other hand, these findings also show that dsDNA and Annexin A1 interact with their respective antibodies on a strictly pH-dependent basis: in both cases, the binding was minimal at pH 4 and maximal at pH9-10.The anionic charge of dsDNA is mainly conferred by the numerous phosphatidic residues. The epitope binding site of Annexin A1 for anti-Annexin A1 IgG2 was here characterized as a string of 34 amino acids at the NH2 terminus, 10 of which are anionic.Circulating levels of anti-dsDNA and anti-Annexin A1 IgG2 antibodies were strongly correlated in patients with systemic lupus erythematosus (n 496) and lupus nephritis (n 425) stratified for age, sex, etc.These results show that dsDNA competes with Annexin A1 for the binding with anti-Annexin A1 IgG2 on a dose and charged mediated base, being able to display an inhibition up to 75%. This study provides the first demonstration that dsDNA may interact with antibodies raised versus other anionic molecules (anti-Annexin A1 IgG2) because of charge mimicry and this interaction may contribute to anti-dsDNA antibodies generation.

SB431542 alleviates lupus nephritis by regulating B cells and inhibiting the TLR9/TGFβ1/PDGFB signaling

Lupus nephritis (LN) is the most common cause of morbidity and mortality in patients with systemic lupus erythematosus (SLE). Currently, immunosuppressive treatments for LN are suboptimal and can induce significant side effects. SB431542 is a selective and potent inhibitor of the TGFβ/Activin/NODAL pathway. Here, we study the effects of SB431542 treatment on LN and discuss the potential mechanisms. SB431542 ameliorated clinical outcomes with a consequent histological improvement in NZB/W mice. A comparative transcriptional profiling analysis revealed 586 differentially expressed genes (247 downregulated genes) in the SB431542 group compared to the control group. We found that the downregulated genes were mainly enriched in the biological processes of B cell activation, B cell proliferation, B cell differentiation, and B cell receptor signaling. Kyoto encyclopedia of genes and genomes pathway analysis revealed that the hematopoietic cell linage pathway was significantly downregulated in the SB431542 group. In addition, we observed that SB431542 reduced the splenic or renal levels of CD20 and the serum levels of anti-dsDNA antibody (IgG) in NZB/W mice. Furthermore, qRT-PCR and immunohistochemistry confirmed that SB431542 inhibits the production of TLR9, TGFβ1, and PDGFB. Thus, due to its immunomodulatory activities, SB431542 could be considered for clinical therapy development for LN.

Subclinical Myocardial Fibrosis in Systemic Lupus Erythematosus as Assessed by Pulse-Cancellation Echocardiography: A Pilot Study.

The aim of this study was to examine whether scar imaging echocardiography with ultrasound multi-pulse scheme (eSCAR) can detect subclinical myocardial involvement in systemic lupus erythematosus (SLE). We consecutively recruited SLE patients and controls matched for age, sex, and cardiovascular risk factors. Participants with cardiac symptoms or a prior history of heart disease were excluded. All participants underwent eSCAR and speckle tracking echocardiography (STE) with global longitudinal strain (GLS) assessment. SLE patients were assessed for disease activity and were followed up for 12 months. Myocardial scars by eSCAR were observed in 19% of SLE patients, almost exclusively localized at the inferoseptal myocardial segments, and in none of the controls. GLS was significantly lower in most myocardial segments of SLE patients compared with the controls, especially in the inferoseptal segments. eSCAR-positive SLE patients received a higher cumulative and current dose of prednisone, and had significantly higher levels of anti-dsDNA antibodies (p = 0.037). eSCAR-positive patients were at higher risk of having SLE flares over follow-up (hazard ratio: 4.91; 95% CI 1.43–16.83; p = 0.0001). We identified inferoseptal myocardial scars by eSCAR in about one-fifth of SLE patients. Subclinical myocardial involvement was associated with glucocorticoid use and anti-dsDNA antibodies.

CD56brightCD16- to CD57+CD56dimCD16+ NK cell ratio discriminates disease activity and renal involvement in patients with systemic lupus erythematosus.

We aimed to discriminate subpopulations of peripheral natural killer (NK) cells of patients with systemic lupus erythematosus (SLE) and evaluate their usability in monitoring disease activity. The total number of NK cells and their subpopulations were determined by flow cytometry in 68 patients with SLE and 35 healthy controls. Clinical data were extracted from medical records, including serum anti-double-stranded-DNA (anti-dsDNA), complement C3 and C4, and urine protein. Disease activity in patients with SLE was assessed using the SLE Disease Activity Index-2000 (SLEDAI-2K). The percentages and absolute numbers of NK cells decreased, and the proportions of three major NK cell subsets defined by cell maturation status altered in SLE patients. The frequency of CD56brightCD16- NK (immature, Im NK) cells increased, while that of the CD57+CD56dimCD16- subset (mature, more differentiated, MD NK) decreased in patients with high-activity SLE, resulting in a significant increase in the Im NK-to-MD NK ratio as compared with that in patients with low-activity SLE. The area under the receiver operating characteristic curve indicated that the ratio was 0.722 in severe SLE and 0.773 in lupus nephritis, with optimal cut-off levels of 0.075 and 0.108, respectively. The ratio correlated positively with the SLEDAI-2K score, proteinuria, and serum anti-dsDNA antibody levels but negatively with C3 and C4 levels. Our data indicate that the imbalance in Im NK and MD NK cells may play a role in lupus development and serve as a predictive biomarker to assess disease activity and renal involvement in patients with SLE.

Comparison of circulating miR-148a and miR-126 with autoantibodies as biomarkers of lupus nephritis in patients with SLE

ABSTRACT Lupus nephritis (LN) is the main manifestation of systemic Lupus Erythematosus (SLE). MicroRNAs (miRNAs) and autoantibodies could be suitable candidate biomarkers of LN. This study evaluates the expression of circulating miR-148a and miR-126 along with anti-dsDNA, anti-C1q, and anti-C3b autoantibodies in SLE patients with LN (SLE + LN). 30 women with SLE, 30 women with SLE + LN, and 25 women as healthy controls (HCs) were enrolled in this study. The plasma expression of selected miRNAs was evaluated by real-time PCR. The serum level of anti-dsDNA, C1q, and C3b antibodies was measured by the ELISA. The expression of miR-148a was significantly increased in SLE and SLE+LN groups compared with the control group. No significant difference was found in the expression of miR-126 among the groups. The frequency of autoantibodies was significantly higher in the SLE + LN group than SLE. The Higher levels of circulating miR-148a in the SLE samples compared with the HCs suggest that this miRNA could be a reliable biomarker for SLE patients (with or without LN). Also, autoantibodies against dsDNA, C1q, and, C3 could be used for the prediction of SLE nephritis, independently. However, further studies are needed to confirm these findings.

Evaluation of red blood cell distribution width-platelet ratio as a predictor of adverse pregnancy outcomes and disease severity in systemic lupus erythematosus.

The red blood cell distribution width to platelet ratio (RPR) is known to reflect systemic inflammation. This study aimed to explore the predictive value of RPR for disease activity and adverse pregnancy outcomes (APOs) in pregnant women with systemic lupus erythematosus (SLE). We retrospectively evaluated case data of all pregnant women with SLE managed at the First Affiliated Hospital of Zhengzhou University from January 2014 to March 2017. Correlations between RPR and SLE clinical disease activity, organ involvement, and maternal complications were analysed. Changes in the RPR and erythrocyte sedimentation rate (ESR) were observed before and after treatment. A receiver operating characteristic (ROC) curve was used to predict disease activity and APOs based on RPR. A total of 118 patients were enrolled, including 77 in the disease-active group and 41 in the disease-inactive group. The live birth rate was significantly higher in the disease-inactive group than in the disease-active group (P < 0.001). Compared to the disease-inactive group, the number of patients with elevated RPR, anti-dsDNA antibody level, and ESR was significantly higher in the disease-active group, whereas their platelet-lymphocyte ratios and complement 3 and 4 levels were significantly lower. The disease-active group was more likely to experience APOs (P < 0.001), mainly due to premature birth, low birth weight, and pregnancy loss. The ROC curve indicated that RPR had an effect on disease activity and APOs. RPR can be used as a predictor of disease severity and APOs in pregnant women with SLE. Key Points • RPR positively correlated with SLEDAI; patients with elevated RPR have higher disease activity, more organ, and more maternal complications. • Monitoring RPR could better predict disease activity in pregnant patients with SLE and reduce the incidence of maternal complications and APOs.

Effects of toxoplasmosis infection on the levels of IL-18 and anti-ds-DNA antibodies in SLE patients

The present study was set to demonstrate the prevalence of toxoplasmosis infection and its effects on patients with systemic lupus erythematosus (SLE) through determining their serum levels of anti-dsDNA and IL-18 antibodies. For this purpose, the sera from 132 SLE and/or toxoplasmosis patients and 30 healthy women, were collected. The study sample was divided into four groups of SLE, toxoplasmosis, SLE coinfected with toxoplasmosis, and healthy control. Anti-Toxoplasma IgG antibodies were examined for all the samples using ELISA kit. The results showed a high mean level of anti-Toxoplasma IgG among SLE patients coinfected with toxoplasmosis (104.8792±12.31585pg/ml) in comparison to that in toxoplasmosis patients (91.1705±12.57746pg/ml). However, the mean value of anti-dsDNA antibodies showed significant (P≤0.01) elevation in SLE patients and SLE patients coinfected with toxoplasmosis (71.2134±9.22131pg/ml and 72.3699±9.67917 pg/ml, respectively), compared to those infected with toxoplasmosis only and healthy control. Furthermore, the IL-18 mean value in the sera of the studied patients showed significant (P≤0.01) elevation (418.4000±43.18072pg/ml) in SLE patients with toxoplasmosis in comparison to SLE patients (354.4400±35.29257pg/ml). The present investigation suggests that the levels of anti-Toxoplasma IgG antibodies seem to increase in patients with SLE.

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

ObjectiveWith 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 MethodsWe 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”.ResultsIn 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–CD27bright 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.ConclusionSRI-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.

Effect of Combined Mycophenolate and Rapamycin Treatment on Kidney Fibrosis in Murine Lupus Nephritis.

Background: A significant proportion of lupus nephritis patients develop chronic kidney disease (CKD) and progressive kidney fibrosis, for which there is no specific treatment. We previously reported that mycophenolate or rapamycin monotherapy showed comparable efficacy in suppressing kidney fibrosis in a murine model of lupus nephritis through their direct action on mesangial cells. We extended our study to investigate the effect of combined mycophenolate and rapamycin treatment (MR) on kidney fibrosis in NZBWF1/J mice. Methods: Female NZBWF1/J mice with active nephritis were randomized to receive vehicle or treatment with mycophenolate (50 mg/kg/day) and rapamycin (1.5 mg/kg/day) (MR) for up to 12 weeks, and the effect of treatment on clinical parameters, kidney histology, and fibrotic processes was investigated. Results: Progression of nephritis in untreated mice was accompanied by mesangial proliferation, glomerulosclerosis, tubular atrophy, protein cast formation, increased mTOR and ERK phosphorylation, and induction of TGF-β1, IL-6, α-smooth muscle actin, fibronectin, and collagen expression. Combined MR treatment prolonged survival, improved kidney function, decreased anti-dsDNA antibody level, and ameliorated histopathological changes. The effect of combined MR treatment on kidney histology and function was comparable to that of mycophenolate or rapamycin monotherapy. In vitro studies in human mesangial cells showed that exogenous TGF-β1 and IL-6 both induced mTOR and ERK phosphorylation and downstream fibrotic processes. Both mycophenolic acid and rapamycin inhibited inflammatory and fibrotic processes induced by TGF-β1 or IL-6 by downregulating mTOR and ERK phosphorylation. Conclusions: Our findings indicate that combined mycophenolate and rapamycin, at reduced dose, improves kidney fibrosis in murine lupus nephritis through their distinct effect on mTOR and ERK signaling in mesangial cells.