Association Between 25(OH) Vitamin D Levels and Adverse Pregnancy Outcomes in Systemic Lupus Erythematosus.

OBJECTIVE: We evaluated the association of 25(OH) vitamin D levels with adverse pregnancy outcomes in systemic lupus erythematosus (SLE). METHODS: The Hopkins Lupus Cohort includes visits of pregnant patients, including assessment of 25(OH) vitamin D at each visit. We examined the relationship between 25(OH) vitamin D levels and adverse pregnancy outcomes (miscarriage, preterm delivery, and small for gestational age). We also used a time-to-event analysis to assess whether time-varying of 25(OH) vitamin D levels were associated with time to miscarriage or preterm delivery. RESULTS: In subgroups of patients defined by the average of 25(OH) vitamin D levels, we observed significantly different risks of miscarriage (p=0.0045), preterm delivery (p=0.0007) and the composite measure of all three adverse pregnancy outcomes (p=0.011). The highest risks were observed among those with lowest or highest levels of vitamin D. Nine out of 10 pregnancies with low vitamin D during the 2nd trimester resulted in a premature delivery. The time-to-event model confirmed the same U-shaped association after adjustment for SLE disease activity, however, the increased risk among those with highest levels of vitamin D was not statistically significant. Body mass index did not appear to be a confounding factor. CONCLUSION: Our study is not able to prove causation, but the results strongly suggest an association of 25(OH) vitamin D at both lower and higher levels with adverse pregnancy outcomes. We recommend monitoring of maternal serum 25(OH) vitamin D levels during SLE pregnancies, aiming for the ideal range of 40-59 ng/mL.

SOX-5 Transcription Factor: a Novel Psoriatic Autoantigen Preferentially Found in Women.

OBJECTIVE: Adaptive immunity mediates psoriatic disease pathogenesis. We aimed to identify novel psoriatic autoantigens and their phenotypic associations in deeply characterized patient cohorts. METHODS: Sera from psoriatic arthritis (PsA) patients were used for autoantibody discovery. Immunoprecipitations performed with cell lysates were on-bead digested, and autoantigens were identified by mass spectrometry. Prevalence and clinical features associated with anti-SRY-Box transcription factor-D (SOX-D) antibodies were determined by screening discovery cohorts of patients with PsA (n = 135), patients with psoriasis without PsA (n = 24), and healthy controls (n = 41). A PsA validation cohort (n = 325) and disease control samples of individuals with rheumatoid arthritis (RA; n = 66) and systemic lupus erythematosus (SLE, n = 66) were assayed for anti-SOX5 antibodies. Disease characteristics were compared by antibody status. Longitudinal data were analyzed using linear mixed-effects models with patient-specific intercept to ascertain associations. We also tested PsA sera for the recently described anti-ADAMTS-L5 autoantibody in PsA. RESULTS: The novel autoantigens identified were SOX-D transcription factors, with SOX-5 being the focus of this analysis. Anti-SOX5 antibodies were present in 8.9% (12 of 135) and 4.3% (14 of 323) of patients in the PsA discovery and validation cohorts, respectively, 12.5% of patients (3 of 24) in the psoriasis group, 2.4% (1 of 41) of healthy controls, and 7.6% (5 of 66) each of patients in the RA and SLE groups. Anti-SOX5 were associated with female sex in both PsA cohorts (discovery: 15.7% women, 2.6% men, P = 0.006; validation: 6.3% women, 1.4% men, P = 0.049). In a longitudinal analysis adjusted for sex, anti-SOX5 associated with biologic disease-modifying antirheumatic drug treatment (95% vs 61%; P = 0.001; n = 96) and with differences in estimated treatment effects by mechanism of action. Anti-ADAMTS-L5 autoantibodies were identified in 8 of 124 patients (6.5%) in the PsA group. CONCLUSION: SOX-D transcription factors are novel psoriatic autoantigens. Anti-SOX5 antibodies were preferentially found in women with PsA and associated with specific clinical and treatment characteristics, suggesting that anti-SOX5 antibodies may identify mechanistic subgroups. We independently validated anti-ADAMTS-L5 autoantibodies in PsA.

Development of the 2023 ACR/EULAR Antiphospholipid Syndrome Classification Criteria, Phase III-D Report: Multi Criteria Decision Analysis.

BACKGROUND: The 2023 ACR/EULAR Antiphospholipid Syndrome (APS) Classification Criteria development, aiming to identify patients with high likelihood of APS for research, employed a four-phase methodology. Phase I and II resulted in 27 proposed candidate criteria, organized into laboratory and clinical domains. Here, we summarize the last stage of Phase III efforts employing a consensus-based multi-criteria decision analysis (MCDA) to weigh candidate criteria and identify an APS classification threshold score. METHODS: We evaluated 192 unique, international real-world cases referred for "suspected APS" with a wide range of APS manifestations. Using proposed candidate criteria, subcommittee members rank-ordered 20 representative cases from highly unlikely to highly likely APS. During an in-person meeting, the subcommittee refined definitions and participated in an MCDA exercise to identify relative weights of candidate criteria. Using consensus decisions and pairwise criteria comparisons, 1000Minds™ software assigned criteria weights, and we rank ordered 192 cases by their additive scores. A consensus-based threshold score for APS classification was set. RESULTS: Pre-meeting evaluation of 20 representative cases demonstrated variability in APS assessment. MCDA resolved 81 pairwise decisions; relative weights identified domain item hierarchy. After assessing 192 cases by weights and additive scores, the Steering Committee reached consensus that APS classification should require separate clinical and laboratory scores, rather than a single aggregate score, to ensure high specificity. CONCLUSION: Using MCDA, candidate criteria preliminary weights were determined. Unlike other disease classification systems using a single aggregate threshold score, separate clinical and laboratory domain thresholds were incorporated into the new APS classification criteria.

Association of Autoantibody Concentrations and Trajectories With Lupus Nephritis Histologic Features and Treatment Response.

OBJECTIVE: Autoantibodies are a hallmark of lupus nephritis (LN), but their association with LN classes and treatment response are not adequately known. In this study, we quantified circulating autoantibodies in the Accelerating Medicines Partnership LN longitudinal cohort to identify serological biomarkers of LN histologic classification and treatment response and how these biomarkers change over time based on treatment response. METHODS: Peripheral blood samples were collected from 279 patients with systemic lupus erythematosus undergoing diagnostic kidney biopsy based on proteinuria. Of these, 268 were diagnosed with LN. Thirteen autoantibody specificities were measured by bead-based assays (Bio-Rad Bioplex 2200) and anti-C1q by enzyme-linked immunosorbent assay at the time of biopsy (baseline) and at 3, 6, and 12 months after biopsy. Clinical response was determined at 12 months. RESULTS: Proliferative LN (International Society of Nephrology/Renal Pathology Society class III/IV±V, n = 160) was associated with higher concentrations of anti-C1q, anti-chromatin, anti-double-stranded DNA (dsDNA), and anti-ribosomal P autoantibodies compared to nonproliferative LN (classes I/II/V/VI, n = 108). Anti-C1q and-dsDNA were independently associated with proliferative LN. In proliferative LN, higher baseline anti-C1q levels predicted complete response (area under the curve [AUC] 0.72; P = 0.002) better than baseline proteinuria (AUC 0.59; P = 0.21). Furthermore, all autoantibody levels except for anti-La/SSB decreased over 12 months in patients with proliferative, but not membranous, LN with a complete response. CONCLUSION: Baseline levels of anti-C1q and anti-dsDNA may serve as noninvasive biomarkers of proliferative LN, and anti-C1q may predict complete response at the time of kidney biopsy. In addition, tracking autoantibodies over time may provide further insights into treatment response and pathogenic mechanisms in patients with proliferative LN.

Hydroxychloroquine Improves Low Complement Levels.

OBJECTIVE: Having a low complement level is associated with clinical systemic lupus erythematosus (SLE) disease activity and future organ damage. We studied the association of hydroxychloroquine (HCQ) whole blood levels with changes in complement level. METHODS: We performed two analyses on data prospectively collected from an SLE cohort. In the first (a "new starts on HCQ" analysis), we compared changes in complement level between those starting HCQ and those not starting it. The second analysis evaluated the association between HCQ whole blood levels and low complement level in all cohort visits using conditional logistic regression. RESULTS: In the "new starts on HCQ" analysis, a higher percentage of patients starting HCQ (as reflected in HCQ blood levels >50) experienced a normalization of C4 level compared to those not starting HCQ (23 of 57 [40%] vs. 9 of 56 [13%]; P = 0.011), as well as a significantly greater increase in both C3 and C4 level (P = 0.048 and P = 0.017, respectively). In the "all cohort visits" analysis, there was a statistically significant higher probability of having normal C4 levels in visits with higher HCQ whole blood levels (odds ratio 1.8-2.6 depending on the levels). This relationship was most pronounced for whole blood HCQ levels of 200 ng/mL or more. CONCLUSION: We observed significant improvement in complement levels when HCQ was started and among those with higher whole blood levels of HCQ, particularly with respect to C4. Modulating the pathogenic mechanisms that lead to complement consumption may be one mode by which HCQ prevents poor outcomes in SLE.

A dual-acting DNASE1/DNASE1L3 biologic prevents autoimmunity and death in genetic and induced lupus models.

A defining feature of systemic lupus erythematosus (SLE) is loss of tolerance to self-DNA, and deficiency of DNASE1L3, the main enzyme responsible for chromatin degradation in blood, is also associated with SLE. This association can be found in an ultrarare population of pediatric patients with DNASE1L3 deficiency who develop SLE, adult patients with loss-of-function variants of DNASE1L3 who are at a higher risk for SLE, and patients with sporadic SLE who have neutralizing autoantibodies against DNASE1L3. To mitigate the pathogenic effects of inherited and acquired DNASE1L3 deficiencies, we engineered a long-acting enzyme biologic with dual DNASE1/DNASE1L3 activity that is resistant to DNASE1 and DNASE1L3 inhibitors. Notably, we found that the biologic prevented the development of lupus in Dnase1-/-Dnase1L3-/- double-knockout mice and rescued animals from death in pristane-induced lupus. Finally, we confirmed that the human isoform of the enzyme biologic was not recognized by autoantibodies in SLE and efficiently degraded genomic and mitochondrial cell-free DNA, as well as microparticle DNA, in SLE plasma. Our findings suggest that autoimmune diseases characterized by aberrant DNA accumulation, such as SLE, can be effectively treated with a replacement DNASE tailored to bypass pathogenic mechanisms, both genetic and acquired, that restrict DNASE1L3 activity.

Prevalence and target attainment of traditional cardiovascular risk factors in patients with systemic lupus erythematosus: a cross-sectional study including 3401 individuals from 24 countries.

BACKGROUND: Systemic lupus erythematosus (SLE) is characterised by increased cardiovascular morbidity and mortality risk. We aimed to examine the prevalence of traditional cardiovascular risk factors and their control in an international survey of patients with systemic lupus erythematosus. METHODS: In this multicentre, cross-sectional study, cardiovascular risk factor data from medical files of adult patients (aged ≥18) with SLE followed between Jan 1, 2015, and Jan 1, 2020, were collected from 24 countries, across five continents. We assessed the prevalence and target attainment of cardiovascular risk factors and examined potential differences by country income level and antiphospholipid syndrome coexistence. We used the Systemic Coronary Risk Evaluation algorithm for cardiovascular risk estimation, and the European Society of Cardiology guidelines for assessing cardiovascular risk factor target attainment. People with lived experience were not involved in the research or writing process. FINDINGS: 3401 patients with SLE were included in the study. The median age was 43·0 years (IQR 33-54), 3047 (89·7%) of 3396 patients were women, 349 (10.3%) were men, and 1629 (48·1%) of 3390 were White. 556 (20·7%) of 2681 patients had concomitant antiphospholipid syndrome. We found a high cardiovascular risk factor prevalence (hypertension 1210 [35·6%] of 3398 patients, obesity 751 [23·7%] of 3169 patients, and hyperlipidaemia 650 [19·8%] of 3279 patients), and suboptimal control of modifiable cardiovascular risk factors (blood pressure [target of <130/80 mm Hg], BMI, and lipids) in the entire SLE group. Higher prevalence of cardiovascular risk factors but a better blood pressure (target of <130/80 mm Hg; 54·9% [1170 of 2132 patients] vs 46·8% [519 of 1109 patients]; p<0·0001), and lipid control (75·0% [895 of 1194 patients] vs 51·4% [386 of 751 patients], p<0·0001 for high-density lipoprotein [HDL]; 66·4% [769 of 1158 patients] vs 60·8% [453 of 745 patients], p=0·013 for non-HDL; 80·9% [1017 of 1257 patients] vs 61·4% [486 of 792 patients], p<0·0001 for triglycerides]) was observed in patients from high-income versus those from middle-income countries. Patients with SLE with antiphospholipid syndrome had a higher prevalence of modifiable cardiovascular risk factors, and significantly lower attainment of BMI and lipid targets (for low-density lipoprotein and non-HDL) than patients with SLE without antiphospholipid syndrome. INTERPRETATION: High prevalence and inadequate cardiovascular risk factor control were observed in a large multicentre and multiethnic SLE cohort, especially among patients from middle-income compared with high-income countries and among those with coexistent antiphospholipid syndrome. Increased awareness of cardiovascular disease risk in SLE, especially in the above subgroups, is urgently warranted. FUNDING: None.

Remission and low disease activity are associated with lower healthcare costs: results from the Systemic Lupus International Collaborating Clinics (SLICC) inception cohort.

OBJECTIVES: This study aims to determine the independent impact of definitions of remission/low disease activity (LDA) on direct/indirect costs (DCs, ICs) in a multicentre inception cohort. METHODS: Patients from 31 centres in 10 countries were enrolled within 15 months of diagnosis and assessed annually. Five mutually exclusive disease activity states (DAS) were defined as (1) remission off-treatment: clinical (c) SLEDAI-2K=0, without prednisone/immunosuppressants; (2) remission on-treatment: cSLEDAI-2K=0, prednisone ≤5 mg/day and/or maintenance immunosuppressants; (3) LDA-Toronto Cohort (TC): cSLEDAI-2K≤2, without prednisone/immunosuppressants; (4) modified lupus LDA state (mLLDAS): SLEDAI-2K≤4, no activity in major organs/systems, no new activity, prednisone ≤7.5 mg/day and/or maintenance immunosuppressants and (5) active: all remaining assessments.At each assessment, patients were stratified into the most stringent DAS fulfilled and the proportion of time in a DAS since cohort entry was determined. Annual DCs/ICs (2021 Canadian dollars) were based on healthcare use and lost workforce/non-workforce productivity over the preceding year.The association between the proportion of time in a DAS and annual DC/IC was examined through multivariable random-effects linear regressions. RESULTS: 1692 patients were followed a mean of 9.7 years; 49.0% of assessments were active. Remission/LDA (per 25% increase in time in a remission/LDA state vs active) were associated with lower annual DC/IC: remission off-treatment (DC -$C1372; IC -$C2507), remission on-treatment (DC -$C973; IC -$C2604,) LDA-TC (DC -$C1158) and mLLDAS (DC -$C1040). There were no cost differences between remission/LDA states. CONCLUSIONS: Our data suggest that systemic lupus erythematosus patients who achieve remission, both off and on-therapy, and reductions in disease activity incur lower costs than those experiencing persistent disease activity.

Uncoupling interferons and the interferon signature explains clinical and transcriptional subsets in SLE.

Systemic lupus erythematosus (SLE) displays a hallmark interferon (IFN) signature. Yet, clinical trials targeting type I IFN (IFN-I) have shown variable efficacy, and blocking IFN-II failed to treat SLE. Here, we show that IFN type levels in SLE vary significantly across clinical and transcriptional endotypes. Whereas skin involvement correlated with IFN-I alone, systemic features like nephritis associated with co-elevation of IFN-I, IFN-II, and IFN-III, indicating additive IFN effects in severe SLE. Notably, while high IFN-II/-III levels without IFN-I had a limited effect on disease activity, IFN-II was linked to IFN-I-independent transcriptional profiles (e.g., OXPHOS and CD8+GZMH+ cells), and IFN-III enhanced IFN-induced gene expression when co-elevated with IFN-I. Moreover, dysregulated IFNs do not explain the IFN signature in 64% of patients or clinical manifestations including cytopenia, serositis, and anti-phospholipid syndrome, implying IFN-independent endotypes in SLE. This study sheds light on mechanisms underlying SLE heterogeneity and the variable response to IFN-targeted therapies in clinical trials.

Anti-KIF20B autoantibodies are associated with cranial neuropathy in systemic lupus erythematosus.

BACKGROUND: Cranial neuropathies (CN) are a rare neuropsychiatric SLE (NPSLE) manifestation. Previous studies reported that antibodies to the kinesin family member 20B (KIF20B) (anti-KIF20B) protein were associated with idiopathic ataxia and CN. We assessed anti-KIF20B as a potential biomarker for NPSLE in an international SLE inception cohort. METHODS: Individuals fulfilling the revised 1997 American College of Rheumatology (ACR) SLE classification criteria were enrolled from 31 centres from 1999 to 2011 and followed annually in the Systemic Lupus Erythematosus International Collaborating Clinics inception cohort. Anti-KIF20B testing was performed on baseline (within 15 months of diagnosis or first annual visit) samples using an addressable laser bead immunoassay. Logistic regression (penalised maximum likelihood and adjusting for confounding variables) examined the association between anti-KIF20B and NPSLE manifestations (1999 ACR case definitions), including CN, occurring over the first 5 years of follow-up. RESULTS: Of the 1827 enrolled cohort members, baseline serum and 5 years of follow-up data were available on 795 patients who were included in this study: 29.8% were anti-KIF20B-positive, 88.7% female, and 52.1% White. The frequency of anti-KIF20B positivity differed only for those with CN (n=10) versus without CN (n=785) (70.0% vs 29.3%; OR 5.2, 95% CI 1.4, 18.5). Compared with patients without CN, patients with CN were more likely to fulfil the ACR haematological (90.0% vs 66.1%; difference 23.9%, 95% CI 5.0%, 42.8%) and ANA (100% vs 95.7%; difference 4.3%, 95% CI 2.9%, 5.8%) criteria. In the multivariate analysis adjusting for age at baseline, female, White race and ethnicity, and ACR haematological and ANA criteria, anti-KIF20B positivity remained associated with CN (OR 5.2, 95% CI 1.4, 19.1). CONCLUSION: Anti-KIF20B is a potential biomarker for SLE-related CN. Further studies are needed to examine how autoantibodies against KIF20B, which is variably expressed in a variety of neurological cells, contribute to disease pathogenesis.

Extrarenal symptoms associate with worse quality of life in patients enrolled in the AMP RA/SLE Lupus Nephritis Network.

OBJECTIVE: Lupus nephritis (LN) can occur as an isolated component of disease activity or be accompanied by diverse extrarenal manifestations. Whether isolated renal disease is sufficient to decrease health related quality of life (HRQOL) remains unknown. This study compared Patient-Reported Outcomes Measurement Information System 29-Item (PROMIS-29) scores in LN patients with isolated renal disease to those with extrarenal symptoms to evaluate the burden of LN on HRQOL and inform future LN clinical trials incorporating HRQOL outcomes. METHODS: A total of 181 LN patients consecutively enrolled in the multicentre multi-ethnic/racial Accelerating Medicines Partnership completed PROMIS-29 questionnaires at the time of a clinically indicated renal biopsy. Raw PROMIS-29 scores were converted to standardized T scores. RESULTS: Seventy-five (41%) patients had extrarenal disease (mean age 34, 85% female) and 106 (59%) had isolated renal (mean age 36, 82% female). Rash (45%), arthritis (40%) and alopecia (40%) were the most common extrarenal manifestations. Compared with isolated renal, patients with extrarenal disease reported significantly worse pain interference, ability to participate in social roles, physical function, and fatigue. Patients with extrarenal disease had PROMIS-29 scores that significantly differed from the general population by > 0.5 SD of the reference mean in pain interference, physical function, and fatigue. Arthritis was most strongly associated with worse scores in these three domains. CONCLUSION: Most patients had isolated renal disease and extrarenal manifestations associated with worse HRQOL. These data highlight the importance of comprehensive disease management strategies that address both renal and extrarenal manifestations to improve overall patient outcomes.

Xist ribonucleoproteins promote female sex-biased autoimmunity.

Autoimmune diseases disproportionately affect females more than males. The XX sex chromosome complement is strongly associated with susceptibility to autoimmunity. Xist long non-coding RNA (lncRNA) is expressed only in females to randomly inactivate one of the two X chromosomes to achieve gene dosage compensation. Here, we show that the Xist ribonucleoprotein (RNP) complex comprising numerous autoantigenic components is an important driver of sex-biased autoimmunity. Inducible transgenic expression of a non-silencing form of Xist in male mice introduced Xist RNP complexes and sufficed to produce autoantibodies. Male SJL/J mice expressing transgenic Xist developed more severe multi-organ pathology in a pristane-induced lupus model than wild-type males. Xist expression in males reprogrammed T and B cell populations and chromatin states to more resemble wild-type females. Human patients with autoimmune diseases displayed significant autoantibodies to multiple components of XIST RNP. Thus, a sex-specific lncRNA scaffolds ubiquitous RNP components to drive sex-biased immunity.

Longitudinal patterns and predictors of response to standard-of-care therapy in lupus nephritis: data from the Accelerating Medicines Partnership Lupus Network.

BACKGROUND: Leveraging the Accelerating Medicines Partnership (AMP) Lupus Nephritis (LN) dataset, we evaluated longitudinal patterns, rates, and predictors of response to standard-of-care therapy in patients with lupus nephritis. METHODS: Patients from US academic medical centers with class III, IV, and/or V LN and a baseline urine protein/creatinine (UPCR) ratio ≥ 1.0 (n = 180) were eligible for this analysis. Complete response (CR) required the following: (1) UPCR < 0.5; (2) normal serum creatinine (≤ 1.3 mg/dL) or, if abnormal, ≤ 125% of baseline; and (3) prednisone ≤ 10 mg/day. Partial response (PR) required the following: (1) > 50% reduction in UPCR; (2) normal serum creatinine or, if abnormal, ≤ 125% of baseline; and (3) prednisone dose ≤ 15 mg/day. RESULTS: Response rates to the standard of care at week 52 were CR = 22.2%; PR = 21.7%; non-responder (NR) = 41.7%, and not determined (ND) = 14.4%. Only 8/180 (4.4%) patients had a week 12 CR sustained through week 52. Eighteen (10%) patients attained a week 12 PR or CR and sustained their responses through week 52 and 47 (26.1%) patients achieved sustained PR or CR at weeks 26 and 52. Week 52 CR or PR attainment was associated with baseline UPCR > 3 (ORadj = 3.71 [95%CI = 1.34-10.24]; p = 0.012), > 25% decrease in UPCR from baseline to week 12 (ORadj = 2.61 [95%CI = 1.07-6.41]; p = 0.036), lower chronicity index (ORadj = 1.33 per unit decrease [95%CI = 1.10-1.62]; p = 0.003), and positive anti-dsDNA antibody (ORadj = 2.61 [95%CI = 0.93-7.33]; p = 0.069). CONCLUSIONS: CR and PR rates at week 52 were consistent with the standard-of-care response rates observed in prospective registrational LN trials. Low sustained response rates underscore the need for more efficacious therapies and highlight how critically important it is to understand the molecular pathways associated with response and non-response.

Thrombosis recurrence and major bleeding in non-anticoagulated thrombotic antiphospholipid syndrome patients: Prospective study from antiphospholipid syndrome alliance for clinical trials and international networking (APS ACTION) clinical database and repository ("Registry").

BACKGROUND: Long-term anticoagulant therapy is generally recommended for thrombotic antiphospholipid syndrome (TAPS) patients, however it may be withdrawn or not introduced in routine practice. OBJECTIVES: To prospectively evaluate the risk of thrombosis recurrence and major bleeding in non-anticoagulated TAPS patients, compared to anticoagulated TAPS, and secondly, to identify different features between those two groups. PATIENTS/METHODS: Using an international registry, we identified non-anticoagulated TAPS patients at baseline, and matched them with anticoagulated TAPS patients based on gender, age, type of previous thrombosis, and associated autoimmune disease. Thrombosis recurrence and major bleeding were prospectively analyzed using Kaplan-Meier method and compared using a marginal Cox's regression model. RESULTS: As of June 2022, 94 (14 %) of the 662 TAPS patients were not anticoagulated; and 93 of them were matched with 181 anticoagulated TAPS patients (median follow-up 5 years [interquartile range 3 to 8]). The 5-year thrombosis recurrence and major bleeding rates were 12 % versus 10 %, and 6 % versus 7 %, respectively (hazard ratio [HR] 1.38, 95 % confidence interval [CI] 0.53 to 3.56, p = 0.50 and HR 0.53; 95 % CI 0.15 to 1.86; p = 0.32, respectively). Non-anticoagulated patients were more likely to receive antiplatelet therapy (p < 0.001), and less likely to have more than one previous thrombosis (p < 0.001) and lupus anticoagulant positivity (p = 0.01). CONCLUSION: Fourteen percent of the TAPS patients were not anticoagulated at recruitment. Their recurrent thrombosis risk did not differ compared to matched anticoagulated TAPS patients, supporting the pressing need for risk-stratified secondary thrombosis prevention trials in APS investigating strategies other than anticoagulation.

Deciphering the clinical significance of longitudinal antiphospholipid antibody titers.

In antiphospholipid syndrome (APS), the risk of clinical manifestations increases with higher titers of antiphospholipid antibodies (aPL). Despite the adoption of aPL titers in the classification approach to aPL-positive subjects, the value of longitudinal monitoring of those titers in the follow-up is still debated, being well studied only in systemic lupus erythematosus (SLE). The literature suggests that the rate of aPL positivity decreases during follow-up in primary APS, estimating that seroconversion occurs in between 8.9 and 59% of patients over time. Negativisation of aPL occurs more frequently in asymptomatic aPL carriers than in patients with full-blown APS as well as in subjects with single aPL positivity or low aPL antibody titers. In patients with SLE, aPL typically behave fluctuating from positive to negative and back again in the course of follow-up. The few studies assessing the longitudinal course of aPL positivity with no associated systemic connective tissue disease reported a progressive decrement of aPL titers over time, in particular of antibodies against ß2 glycoprotein I (antiß2GPI) and cardiolipin (aCL) of IgG isotype. After a thrombotic event, aPL titers tend to decrease, as emerged from cohorts of both primary and secondary APS. Hydroxychloroquine has been identified as the most effective pharmacological agent to reduce aPL titers, with multiple studies demonstrating a parallel reduction in thrombosis rate. This review addresses available evidence on the significance of aPL titer fluctuation from clinical, therapeutic and pathogenic perspectives.

Blood immunophenotyping identifies distinct kidney histopathology and outcomes in patients with lupus nephritis.

Lupus nephritis (LN) is a frequent manifestation of systemic lupus erythematosus, and fewer than half of patients achieve complete renal response with standard immunosuppressants. Identifying non-invasive, blood-based pathologic immune alterations associated with renal injury could aid therapeutic decisions. Here, we used mass cytometry immunophenotyping of peripheral blood mononuclear cells in 145 patients with biopsy-proven LN and 40 healthy controls to evaluate the heterogeneity of immune activation in patients with LN and to identify correlates of renal parameters and treatment response. Unbiased analysis identified 3 immunologically distinct groups of patients with LN that were associated with different patterns of histopathology, renal cell infiltrates, urine proteomic profiles, and treatment response at one year. Patients with enriched circulating granzyme B+ T cells at baseline showed more severe disease and increased numbers of activated CD8 T cells in the kidney, yet they had the highest likelihood of treatment response. A second group characterized primarily by a high type I interferon signature had a lower likelihood of response to therapy, while a third group appeared immunologically inactive by immunophenotyping at enrollment but with chronic renal injuries. Main immune profiles could be distilled down to 5 simple cytometric parameters that recapitulate several of the associations, highlighting the potential for blood immune profiling to translate to clinically useful non-invasive metrics to assess immune-mediated disease in LN.

Urine proteomic signatures of histological class, activity, chronicity, and treatment response in lupus nephritis.

Lupus nephritis (LN) is a pathologically heterogenous autoimmune disease linked to end-stage kidney disease and mortality. Better therapeutic strategies are needed as only 30%-40% of patients completely respond to treatment. Noninvasive biomarkers of intrarenal inflammation may guide more precise approaches. Because urine collects the byproducts of kidney inflammation, we studied the urine proteomic profiles of 225 patients with LN (573 samples) in the longitudinal Accelerating Medicines Partnership in RA/SLE cohort. Urinary biomarkers of monocyte/neutrophil degranulation (i.e., PR3, S100A8, azurocidin, catalase, cathepsins, MMP8), macrophage activation (i.e., CD163, CD206, galectin-1), wound healing/matrix degradation (i.e., nidogen-1, decorin), and IL-16 characterized the aggressive proliferative LN classes and significantly correlated with histological activity. A decline of these biomarkers after 3 months of treatment predicted the 1-year response more robustly than proteinuria, the standard of care (AUC: CD206 0.91, EGFR 0.9, CD163 0.89, proteinuria 0.8). Candidate biomarkers were validated and provide potentially treatable targets. We propose these biomarkers of intrarenal immunological activity as noninvasive tools to diagnose LN and guide treatment and as surrogate endpoints for clinical trials. These findings provide insights into the processes involved in LN activity. This data set is a public resource to generate and test hypotheses and validate biomarkers.

Immune and molecular landscape behind non-response to Mycophenolate Mofetil and Azathioprine in lupus nephritis therapy.

Lupus nephritis (LN) represents one of the most severe complications of systemic lupus erythematosus, leading to end-stage kidney disease in worst cases. Current first-line therapies for LN, including mycophenolate mofetil (MMF) and azathioprine (AZA), fail to induce long-term remission in 60-70% of the patients, evidencing the urgent need to delve into the molecular knowledge-gap behind the non-response to these therapies. A longitudinal cohort of treated LN patients including clinical, cellular and transcriptomic data, was analyzed. Gene-expression signatures behind non-response to different drugs were revealed by differential expression analysis. Drug-specific non-response mechanisms and cell proportion differences were identified. Blood cell subsets mediating non-response were described using single-cell RNASeq data. We show that AZA and MMF non-response implicates different cells and regulatory functions. Mechanistic models were used to suggest add-on therapies to improve their current performance. Our results provide new insights into the molecular mechanisms associated with treatment failures in LN.

EULAR recommendations for the management of systemic lupus erythematosus: 2023 update.

OBJECTIVES: To update the EULAR recommendations for the management of systemic lupus erythematosus (SLE) based on emerging new evidence. METHODS: An international Task Force formed the questions for the systematic literature reviews (January 2018-December 2022), followed by formulation and finalisation of the statements after a series of meetings. A predefined voting process was applied to each overarching principle and recommendation. Levels of evidence and strengths of recommendation were assigned, and participants finally provided their level of agreement with each item. RESULTS: The Task Force agreed on 5 overarching principles and 13 recommendations, concerning the use of hydroxychloroquine (HCQ), glucocorticoids (GC), immunosuppressive drugs (ISDs) (including methotrexate, mycophenolate, azathioprine, cyclophosphamide (CYC)), calcineurin inhibitors (CNIs, cyclosporine, tacrolimus, voclosporin) and biologics (belimumab, anifrolumab, rituximab). Advice is also provided on treatment strategies and targets of therapy, assessment of response, combination and sequential therapies, and tapering of therapy. HCQ is recommended for all patients with lupus at a target dose 5 mg/kg real body weight/day, considering the individual's risk for flares and retinal toxicity. GC are used as 'bridging therapy' during periods of disease activity; for maintenance treatment, they should be minimised to equal or less than 5 mg/day (prednisone equivalent) and, when possible, withdrawn. Prompt initiation of ISDs (methotrexate, azathioprine, mycophenolate) and/or biological agents (anifrolumab, belimumab) should be considered to control the disease and facilitate GC tapering/discontinuation. CYC and rituximab should be considered in organ-threatening and refractory disease, respectively. For active lupus nephritis, GC, mycophenolate or low-dose intravenous CYC are recommended as anchor drugs, and add-on therapy with belimumab or CNIs (voclosporin or tacrolimus) should be considered. Updated specific recommendations are also provided for cutaneous, neuropsychiatric and haematological disease, SLE-associated antiphospholipid syndrome, kidney protection, as well as preventative measures for infections, osteoporosis, cardiovascular disease. CONCLUSION: The updated recommendations provide consensus guidance on the management of SLE, combining evidence and expert opinion.

Damage measured by Damage Index for Antiphospholipid Syndrome (DIAPS) in antiphospholipid antibody-positive patients included in the APS ACTION registry.

OBJECTIVES: Our primary objective was to quantify damage burden measured by Damage Index for Antiphospholipid Syndrome (DIAPS) in aPL-positive patients with or without a history of thrombosis in an international cohort (the APS ACTION cohort). Secondly, we aimed to identify clinical and laboratory characteristics associated with damage in aPL-positive patients. METHODS: In this cross-sectional study, we analysed the baseline damage in aPL-positive patients with or without APS classification. We excluded patients with other autoimmune diseases. We analysed the demographic, clinical and laboratory characteristics based on two subgroups: (i) thrombotic APS patients with high vs low damage; and (ii) non-thrombotic aPL-positive patients with vs without damage. RESULTS: Of the 826 aPL-positive patients included in the registry as of April 2020, 586 with no other systemic autoimmune diseases were included in the analysis (412 thrombotic and 174 non-thrombotic). In the thrombotic group, hyperlipidaemia (odds ratio [OR] 1.82; 95% CI 1.05, 3.15; adjusted P = 0.032), obesity (OR 2.14; 95% CI 1.23, 3.71; adjusted P = 0.007), aß2GPI high titres (OR 2.33; 95% CI 1.36, 4.02; adjusted P = 0.002) and corticosteroid use (ever) (OR 3.73; 95% CI 1.80, 7.75; adjusted P < 0.001) were independently associated with high damage at baseline. In the non-thrombotic group, hypertension (OR 4.55; 95% CI 1.82, 11.35; adjusted P = 0.001) and hyperlipidaemia (OR 4.32; 95% CI 1.37, 13.65; adjusted P = 0.013) were independent predictors of damage at baseline; conversely, single aPL positivity was inversely correlated with damage (OR 0.24; 95% CI 0.075, 0.77; adjusted P = 0.016). CONCLUSIONS: DIAPS indicates substantial damage in aPL-positive patients in the APS ACTION cohort. Selected traditional cardiovascular risk factors, steroids use and specific aPL profiles may help to identify patients more prone to present with a higher damage burden.