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.

Urinary HER2, TWEAK and VCAM-1 levels are associated with new-onset proteinuria in paediatric lupus nephritis.

OBJECTIVE: Lupus nephritis is a key driver of morbidity and mortality in SLE. Detecting active nephritis on a background of pre-existing renal damage is difficult, leading to potential undertreatment and accumulating injury. An unmet need is a biomarker that distinguishes active lupus nephritis, particularly important in paediatrics where minimising invasive procedures is desirable. METHODS: This was a multicentre, prospective study of 113 paediatric patients with biopsy-proven lupus nephritis. Clinical data and urine were obtained every 3-4 months and patients averaged 2 years on study with seven time points. Urine was analysed for human epidermal growth factor receptor 2 (HER2), tumour necrosis factor-like weak inducer of apoptosis and vascular cell adhesion molecule-1 (VCAM-1) by ELISA. We defined active disease as either a rise in serum creatinine ≥0.3 mg/dL from baseline or a rise in renal Systemic Lupus Erythematosus Disease Activity Index score from the previous visit. These markers were also studied in patients with acute kidney injury, juvenile idiopathic arthritis (JIA), amplified pain syndrome and healthy controls. RESULTS: The rate of active disease was 56% over an average of 2 years of follow-up. HER2 and VCAM-1 were significantly elevated at time points with active disease defined by increased serum creatinine compared with time points with inactive disease or patients who never flared. All three biomarkers were associated with new-onset proteinuria and VCAM-1 was elevated at time points preceding new-onset proteinuria. These biomarkers were not increased in acute kidney injury or JIA. CONCLUSION: All three biomarkers were associated with new onset proteinuria and increased VCAM-1 may predict impending proteinuria. These biomarkers provide potential non-invasive measures for monitoring that may be more sensitive to impending flare than conventional measures.

Renal response at 2 years post biopsy to predict long-term renal survival in lupus nephritis: a retrospective analysis of the Hopkins Lupus Cohort.

OBJECTIVE: This retrospective analysis evaluated the prognostic value of renal response status 2 years after biopsy-proven lupus nephritis (LN) for the prediction of long-term renal outcomes. METHODS: Eligible patients with SLE as per American College of Rheumatology or Systemic Lupus International Collaborating Clinics criteria and biopsy-proven class III, IV, V or mixed LN were identified from the Hopkins Lupus Cohort, and categorised into binary renal response categories (modified primary efficacy renal response (mPERR) or no mPERR at 2 years post biopsy). These categories were defined by a modified version of the Belimumab International Lupus Nephritis Study (BLISS-LN) protocol using urine protein:creatinine ratio (≤0.7 g/day) and estimated glomerular filtration rate (≥60 mL/min/1.73 m2 or ≤20% below the baseline value) criteria. Long-term renal survival (defined as survival without end-stage renal disease (ESRD) or death) and chronic renal insufficiency-free survival were assessed in Kaplan-Meier plots with log-rank test and covariate-adjusted Cox proportional hazards models. RESULTS: Of the 173 eligible patients, 91.3% were female; the mean (SD) age at biopsy was 36.2 (11.8) years. At 2 years post biopsy, 114 (65.9%) patients achieved mPERR. These patients showed a lower risk of ESRD/death and chronic renal insufficiency in the follow-up period (HR (95% CI) 0.33 (0.13 to 0.87), p=0.0255; and HR (95% CI) 0.26 (0.14 to 0.47), p<0.0001, respectively). CONCLUSIONS: The 2-year post-biopsy renal response status, defined per 2019-updated BLISS-LN criteria, has prognostic value for long-term renal survival and lower risk of chronic renal insufficiency in patients with LN.

Clinical and histopathological features of myositis in systemic lupus erythematosus.

OBJECTIVE: The objectives of this study were to compare the clinical features of patients with SLE with and without myopathy and to describe the muscle biopsy features of patients with SLE myopathy. METHODS: This nested case-control study included all subjects enrolled in the Hopkins Lupus Cohort database from May 1987 to June 2016. Subjects with elevated creatine kinase along with evidence of muscle oedema on MRI, myopathic electromyography and/or myopathic muscle biopsy features were defined as having SLE myopathy. Demographic, serological and clinical features were compared between patients with SLE with and without myopathy. Muscle biopsies were histologically classified as polymyositis, dermatomyositis, necrotising myopathy or non-specific myositis. RESULTS: From among 2437 patients with SLE, 179 (7.3%) had myopathy. African American patients were more likely to develop myositis than Caucasian patients (p<0.0001). Compared with those without myopathy, patients with SLE myopathy were more likely to have malar rash (OR 1.67, 1.22-2.29), photosensitivity (OR 1.43, 1.04-1.96), arthritis (OR 1.81, 1.21-2.69), pleurisy (OR 1.77, 1.3-2.42), pericarditis (OR 1.49, 1.06-2.08), acute confusional state (OR 2.07, 1.09-3.94), lymphopaenia (OR 1.64, 1.2-2.24), anti-double-stranded DNA antibodies (OR 1.52, 1.09-2.13), lupus anticoagulant (OR 1.42, 1-2), cognitive impairment (OR 1.87, 1.12-3.13), cataract (OR 1.5, 1.04-2.18), pulmonary hypertension (OR 1.98, 1.13-3.47), pleural fibrosis (OR 2.01, 1.27-3.18), premature gonadal failure (OR 1.9, 1.05-3.43), diabetes (OR 1.92, 1.22-3.02) or hypertension (OR 1.45, 1.06-2). Among 16 muscle biopsies available for review, the most common histological classifications were necrotising myositis (50%) and dermatomyositis (38%). CONCLUSIONS: Patients with SLE myopathy have a higher prevalence of numerous SLE disease manifestations. Necrotising myopathy and dermatomyositis are the most prevalent histopathological features in SLE myopathy.

Safety of procuring research tissue during a clinically indicated kidney biopsy from patients with lupus: data from the Accelerating Medicines Partnership RA/SLE Network.

OBJECTIVES: In lupus nephritis the pathological diagnosis from tissue retrieved during kidney biopsy drives treatment and management. Despite recent approval of new drugs, complete remission rates remain well under aspirational levels, necessitating identification of new therapeutic targets by greater dissection of the pathways to tissue inflammation and injury. This study assessed the safety of kidney biopsies in patients with SLE enrolled in the Accelerating Medicines Partnership, a consortium formed to molecularly deconstruct nephritis. METHODS: 475 patients with SLE across 15 clinical sites in the USA consented to obtain tissue for research purposes during a clinically indicated kidney biopsy. Adverse events (AEs) were documented for 30 days following the procedure and were determined to be related or unrelated by all site investigators. Serious AEs were defined according to the National Institutes of Health reporting guidelines. RESULTS: 34 patients (7.2%) experienced a procedure-related AE: 30 with haematoma, 2 with jets, 1 with pain and 1 with an arteriovenous fistula. Eighteen (3.8%) experienced a serious AE requiring hospitalisation; four patients (0.8%) required a blood transfusion related to the kidney biopsy. At one site where the number of cores retrieved during the biopsy was recorded, the mean was 3.4 for those who experienced a related AE (n=9) and 3.07 for those who did not experience any AE (n=140). All related AEs resolved. CONCLUSIONS: Procurement of research tissue should be considered feasible, accompanied by a complication risk likely no greater than that incurred for standard clinical purposes. In the quest for targeted treatments personalised based on molecular findings, enhanced diagnostics beyond histology will likely be required.

Intracellular homocysteine metabolites in SLE: plasma S-adenosylhomocysteine correlates with coronary plaque burden.

BACKGROUND AND AIMS: We hypothesised that intracellular homocysteine and homocysteine metabolite levels in patients with SLE are disproportionately elevated compared with the levels seen in healthy subjects and that they are independently associated with coronary plaque in SLE. METHODS: A liquid chromatography-tandem mass spectrometry absolute quantification assay was used for the determination of six analytes in both plasma and peripheral blood mononuclear cells (PBMCs): homocysteine (Hcy), S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH), methionine (Met), cystathionine (Cysta) and 5-methyltetrahydrofolate (5m-THF). We then compared intracellular (PBMC) and extracellular (plasma) Hcy and Hcy metabolite (SAM, SAH, Met, Cysta and 5m-THF) concentrations in 10 patients with SLE and in 10 age, sex and ethnicity matched controls. Subjects with a history of diabetes mellitus, cardiovascular disease, hypertension, alcohol consumption in excess of 3 units per day, anaemia, renal insufficiency (serum creatinine >1.5 mg/dL) and pregnancy were excluded. All patients with SLE had two coronary CT angiography studies as screening for occult coronary atherosclerotic disease. RESULTS: Plasma from patients with SLE had higher levels of Hcy (p<0.0001), SAH (p<0.05), SAM (p<0.001) and lower levels of Met (p<0.05) and Cysta (p<0.001) compared with controls. PBMC intracellular concentrations from patients with SLE had higher levels of Cysta (p<0.05), SAH (p<0.05), SAM (p<0.001) and lower levels of 5m-THF (p<0.001). Plasma SAH showed a positive correlation with total coronary plaque, calcified plaque and non-calcified plaque (p<0.05). CONCLUSION: Intracellular concentrations of Hcy metabolites were significantly different between patients with SLE and controls, despite similar intracellular Hcy levels. Plasma SAH was positively correlated with total coronary plaque, calcified plaque and non-calcified plaque.

Cancer Risk in a Large Inception Systemic Lupus Erythematosus Cohort: Effects of Demographic Characteristics, Smoking, and Medications.

OBJECTIVE: To assess cancer risk factors in incident systemic lupus erythematosus (SLE). METHODS: Clinical variables and cancer outcomes were assessed annually among incident SLE patients. Multivariate hazard regression models (overall risk and most common cancers) included demographic characteristics and time-dependent medications (corticosteroids, antimalarial drugs, immunosuppressants), smoking, and the adjusted mean Systemic Lupus Erythematosus Disease Activity Index 2000 score. RESULTS: Among 1,668 patients (average 9 years follow-up), 65 cancers occurred: 15 breast, 10 nonmelanoma skin, 7 lung, 6 hematologic, 6 prostate, 5 melanoma, 3 cervical, 3 renal, 2 each gastric, head and neck, and thyroid, and 1 each rectal, sarcoma, thymoma, and uterine cancers. Half of the cancers (including all lung cancers) occurred in past/current smokers, versus one-third of patients without cancer. Multivariate analyses indicated that overall cancer risk was related primarily to male sex and older age at SLE diagnosis. In addition, smoking was associated with lung cancer. For breast cancer risk, age was positively associated and antimalarial drugs were negatively associated. Antimalarial drugs and higher disease activity were also negatively associated with nonmelanoma skin cancer risk, whereas age and cyclophosphamide were positively associated. Disease activity was associated positively with hematologic and negatively with nonmelanoma skin cancer risk. CONCLUSION: Smoking is a key modifiable risk factor, especially for lung cancer, in SLE. Immunosuppressive medications were not clearly associated with higher risk except for cyclophosphamide and nonmelanoma skin cancer. Antimalarials were negatively associated with breast cancer and nonmelanoma skin cancer risk. SLE activity was associated positively with hematologic cancer and negatively with nonmelanoma skin cancer. Since the absolute number of cancers was small, additional follow-up will help consolidate these findings.

Cutaneous vasculitis in SLE.

OBJECTIVES: We determined the temporal association between clinical and serological disease manifestations and development of cutaneous small vessel vasculitis in a large prospective multiethnic cohort. METHODS: Patients with SLE diagnosed according to the Systemic Lupus International Collaborating Clinics (SLICC) classification criteria or the revised classification criteria as defined by the American College of Rheumatology (ACR) were enrolled in the Hopkins Lupus Cohort. Cutaneous small vessel vasculitis was determined as a component of the Systemic Lupus Erythematosus Disease Activity Index. SLE-associated cutaneous small vessel vasculitis lesions were reported clinically. They presented as punctate lesions, palpable purpura, tender erythematous plaques or macules with or without necrosis. No histopathological diagnosis was pursued to confirm the diagnosis of vasculitis or to differentiate it from other causes of digital lesions in patients with SLE. Disease manifestations that preceded the first occurrence of cutaneous small vessel vasculitis lesions were analysed using Kaplan-Meier. Cox regression analysis was used to assess the relationship between baseline clinical and immunological manifestations and the development of cutaneous small vessel vasculitis. We adjusted for gender, race and age at SLE diagnosis. RESULTS: A total of 2580 patients were studied: 52.4% were Caucasian and 39.4% were African-American. The mean age of the cohort was 45.5±14.5 years. The mean years of cohort follow-up was 7.9±7.6. Cutaneous small vessel vasculitis was observed in 449 (17.3%). The mean time to cutaneous vasculitis after SLE diagnosis was 4.78 years (95% CI 3.96 to 5.60). At least 159 (35%) patients had recurrences of cutaneous vasculitis lesions. Discoid rash, Raynaud's phenomenon, myositis, anaemia, Coombs' positivity, leucopenia, anti-Smith and anti-RNP (Ribonucleoprotein) were significantly associated with the development of cutaneous vasculitis. The SLICC/ACR Damage Index score was higher in patients with cutaneous vasculitis compared with those without cutaneous vasculitis. CONCLUSIONS: Cutaneous vasculitis is frequent (17.3%) and often recurrent (35%). African-Americans are at higher risk of developing cutaneous small vessel vasculitis than Caucasians. Clinical presentations such as myositis and haematological manifestations are predictors of cutaneous vasculitis development. The presence of cutaneous vasculitis is associated with increased organ damage.

Low hydroxychloroquine blood levels in patients who have had gastric bypass surgery.

Gastric bypass surgery, also called Roux-en-Y gastric bypass (RYGB), can result in the malabsorption of medications, requiring the use of higher than usual doses in order to achieve a therapeutic effect. We describe the results of hydroxychloroquine (HCQ) blood levels in three patients with systemic autoimmune disease taking standard HCQ doses and their associated disease activity levels. This is a retrospective review of all patients who had undergone RYGB and were taking HCQ in a rheumatology community-based practice. Two patients with SLE and one patient with primary Sjogren's syndrome had previously undergone RYGB. All three had subtherapeutic HCQ blood levels and active disease. Increasing their HCQ doses above the recommended 400 mg a day dosing resulted in therapeutic HCQ levels in all three patients and better disease control in two of the three patients. RYGB patients may not absorb HCQ adequately, resulting in subtherapeutic HCQ blood levels and inadequate disease control. Patients who have undergone RYGB and are taking HCQ should have drug levels monitored. RYGB patients may require higher than recommended doses of HCQ in order to achieve better disease control and avoid unneeded additional immunosuppressive agents.

The immune cell landscape in kidneys of patients with lupus nephritis.

Lupus nephritis is a potentially fatal autoimmune disease for which the current treatment is ineffective and often toxic. To develop mechanistic hypotheses of disease, we analyzed kidney samples from patients with lupus nephritis and from healthy control subjects using single-cell RNA sequencing. Our analysis revealed 21 subsets of leukocytes active in disease, including multiple populations of myeloid cells, T cells, natural killer cells and B cells that demonstrated both pro-inflammatory responses and inflammation-resolving responses. We found evidence of local activation of B cells correlated with an age-associated B-cell signature and evidence of progressive stages of monocyte differentiation within the kidney. A clear interferon response was observed in most cells. Two chemokine receptors, CXCR4 and CX3CR1, were broadly expressed, implying a potentially central role in cell trafficking. Gene expression of immune cells in urine and kidney was highly correlated, which would suggest that urine might serve as a surrogate for kidney biopsies.

Preferential association of a functional variant in complement receptor 2 with antibodies to double-stranded DNA.

OBJECTIVES: Systemic lupus erythematosus (SLE; OMIM 152700) is characterised by the production of antibodies to nuclear antigens. We previously identified variants in complement receptor 2 (CR2/CD21) that were associated with decreased risk of SLE. This study aimed to identify the causal variant for this association. METHODS: Genotyped and imputed genetic variants spanning CR2 were assessed for association with SLE in 15 750 case-control subjects from four ancestral groups. Allele-specific functional effects of associated variants were determined using quantitative real-time PCR, quantitative flow cytometry, electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP)-PCR. RESULTS: The strongest association signal was detected at rs1876453 in intron 1 of CR2 (pmeta=4.2×10(-4), OR 0.85), specifically when subjects were stratified based on the presence of dsDNA autoantibodies (case-control pmeta=7.6×10(-7), OR 0.71; case-only pmeta=1.9×10(-4), OR 0.75). Although allele-specific effects on B cell CR2 mRNA or protein levels were not identified, levels of complement receptor 1 (CR1/CD35) mRNA and protein were significantly higher on B cells of subjects harbouring the minor allele (p=0.0248 and p=0.0006, respectively). The minor allele altered the formation of several DNA protein complexes by EMSA, including one containing CCCTC-binding factor (CTCF), an effect that was confirmed by ChIP-PCR. CONCLUSIONS: These data suggest that rs1876453 in CR2 has long-range effects on gene regulation that decrease susceptibility to lupus. Since the minor allele at rs1876453 is preferentially associated with reduced risk of the highly specific dsDNA autoantibodies that are present in preclinical, active and severe lupus, understanding its mechanisms will have important therapeutic implications.

Lymphoma risk in systemic lupus: effects of disease activity versus treatment.

OBJECTIVE: To examine disease activity versus treatment as lymphoma risk factors in systemic lupus erythematosus (SLE). METHODS: We performed case-cohort analyses within a multisite SLE cohort. Cancers were ascertained by regional registry linkages. Adjusted HRs for lymphoma were generated in regression models, for time-dependent exposures to immunomodulators (cyclophosphamide, azathioprine, methotrexate, mycophenolate, antimalarial drugs, glucocorticoids) demographics, calendar year, Sjogren's syndrome, SLE duration and disease activity. We used adjusted mean SLE Disease Activity Index scores (SLEDAI-2K) over time, and drugs were treated both categorically (ever/never) and as estimated cumulative doses. RESULTS: We studied 75 patients with lymphoma (72 non-Hodgkin, three Hodgkin) and 4961 cancer-free controls. Most lymphomas were of B-cell origin. As is seen in the general population, lymphoma risk in SLE was higher in male than female patients and increased with age. Lymphomas occurred a mean of 12.4 years (median 10.9) after SLE diagnosis. Unadjusted and adjusted analyses failed to show a clear association of disease activity with lymphoma risk. There was a suggestion of greater exposure to cyclophosphamide and to higher cumulative steroids in lymphoma cases than the cancer-free controls. CONCLUSIONS: In this large SLE sample, there was a suggestion of higher lymphoma risk with exposure to cyclophosphamide and high cumulative steroids. Disease activity itself was not clearly associated with lymphoma risk. Further work will focus on genetic profiles that might interact with medication exposure to influence lymphoma risk in SLE.

Baseline predictors of systemic lupus erythematosus flares: data from the combined placebo groups in the phase III belimumab trials.

OBJECTIVE: To identify predictors of moderate-to-severe systemic lupus erythematosus (SLE) flare in 562 patients treated with standard therapy alone in phase III belimumab trials, and to evaluate the impact of standard therapies on preventing flares. METHODS: Post hoc analysis assessed baseline demographics, disease activity, and biomarkers in patients with and those without flare at treatment weeks 24 and 52. Severe flare was defined by the modified SLE Flare Index (SFI) and the development of any new British Isles Lupus Assessment Group (BILAG) A domain score. Severe and moderate flare was defined by development of 1 new BILAG A domain score or 2 new BILAG B domain scores. Baseline characteristics associated with a ≥10% absolute difference or a ≥50% increase in flare rates were considered predictive. RESULTS: Frequencies of flares over 52 weeks according to the SFI, any new BILAG A domain score, and 1 new BILAG A domain score or 2 new BILAG B domain scores were 23.7%, 23.1%, and 32.0%, respectively. Flare predictors by univariate analysis on all 3 indices at weeks 24 and 52 were a score ≥12 on the Safety of Estrogens in Lupus Erythematosus National Assessment version of the SLE Disease Activity Index (SELENA-SLEDAI); anti-double-stranded DNA (anti-dsDNA) positivity; proteinuria (≥0.5 gm/24 hours); BILAG renal, vasculitic, and hematologic scores; elevated C-reactive protein levels; and B lymphocyte stimulator (BLyS) levels ≥2 ng/ml. Independent predictors by multivariate analysis at week 52 were SELENA-SLEDAI and/or BILAG renal involvement and anti-dsDNA ≥200 IU/ml (on all 3 indices); SELENA-SLEDAI and/or BILAG neurologic and vasculitic involvement (on 2 indices: any new BILAG A domain score and 1 new BILAG A domain score or 2 new BILAG B domain scores); BLyS levels ≥2 ng/ml (on 2 indices: the SFI and 1 new BILAG A domain score or 2 new BILAG B domain scores); and low C3 level (on the SFI). Baseline medications did not significantly decrease or increase moderate-to-severe SLE flare risk. CONCLUSION: Patients who were receiving standard SLE therapy and had renal, neurologic, or vasculitic involvement, elevated anti-dsDNA or BLyS levels, or low C3 had increased risk of clinically meaningful flare over 1 year. Hydroxychloroquine use was not predictive.

Association of two independent functional risk haplotypes in TNIP1 with systemic lupus erythematosus.

OBJECTIVE: Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by autoantibody production and altered type I interferon expression. Genetic surveys and genome-wide association studies have identified >30 SLE susceptibility genes. One of these genes, TNIP1, encodes the ABIN1 protein. ABIN1 functions in the immune system by restricting NF-κB signaling. The present study was undertaken to investigate the genetic factors that influence association with SLE in genes that regulate the NF-κB pathway. METHODS: We analyzed a dense set of genetic markers spanning TNIP1 and TAX1BP1, as well as the TNIP1 homolog TNIP2, in case-control populations of diverse ethnic origins. TNIP1, TNIP2, and TAX1BP1 were fine-mapped in a total of 8,372 SLE cases and 7,492 healthy controls from European-ancestry, African American, Hispanic, East Asian, and African American Gullah populations. Levels of TNIP1 messenger RNA (mRNA) and ABIN1 protein in Epstein-Barr virus-transformed human B cell lines were analyzed by quantitative reverse transcription-polymerase chain reaction and Western blotting, respectively. RESULTS: We found significant associations between SLE and genetic variants within TNIP1, but not in TNIP2 or TAX1BP1. After resequencing and imputation, we identified 2 independent risk haplotypes within TNIP1 in individuals of European ancestry that were also present in African American and Hispanic populations. Levels of TNIP1 mRNA and ABIN1 protein were reduced among subjects with these haplotypes, suggesting that they harbor hypomorphic functional variants that influence susceptibility to SLE by restricting ABIN1 expression. CONCLUSION: Our results confirm the association signals between SLE and TNIP1 variants in multiple populations and provide new insight into the mechanism by which TNIP1 variants may contribute to SLE pathogenesis.

Genetic risk factors for thrombosis in systemic lupus erythematosus.

OBJECTIVE: Thrombosis is a serious complication of systemic lupus erythematosus (SLE). We investigated whether genetic variants implicated in thrombosis pathways are associated with thrombosis among 2 ethnically diverse SLE cohorts. METHODS: Our discovery cohort consisted of 1698 patients with SLE enrolled in the University of California, San Francisco, Lupus Genetics Project and our replication cohort included 1361 patients with SLE enrolled in the PROFILE cohort. Patients fulfilled American College of Rheumatology SLE criteria, and data relevant to thrombosis were available. Thirty-three single nucleotide polymorphisms (SNP) previously shown to be associated with risk of deep venous thrombosis in the general population or implicated in thrombosis pathways were genotyped and tested for association with thrombosis in bivariate allelic analyses. SNP with p < 0.1 in the bivariate analyses were further tested in multivariable logistic regression models adjusted for age, sex, disease duration, antiphospholipid antibody status, smoking, nephritis, and medications. RESULTS: In the discovery cohort, 23% of patients with SLE experienced a thrombotic event. SNP in the following genes demonstrated association with thrombosis risk overall in the discovery or replication cohorts and were assessed using metaanalytic methods: factor V Leiden (FVL) rs6025 (OR 1.85, p = 0.02) and methylenetetrahydrofolate reductase (MTHFR) rs1801133 (OR 0.75, p = 0.04) in whites, and fibrinogen gamma (FGG) rs2066865 (OR 1.91, p = 0.01) in Hispanic Americans. SNP in these genes showed association with venous thrombosis risk in whites: MTHFR rs1801131 (OR 1.51, p = 0.01), MTHFR rs1801133 (OR 0.70, p = 0.04), FVL rs6025 (OR 2.69, p = 0.002), and FGG rs2066865 (OR 1.49, p = 0.02) in whites. A SNP in FGG rs2066865 (OR 2.19, p = 0.003) demonstrated association with arterial thrombosis risk in Hispanics. CONCLUSION: Our results implicate specific genetic risk factors for thrombosis in patients with SLE and suggest that genetic risk for thrombosis differs across ethnic groups.

Effects of belimumab, a B lymphocyte stimulator-specific inhibitor, on disease activity across multiple organ domains in patients with systemic lupus erythematosus: combined results from two phase III trials.

OBJECTIVE: To evaluate the effects of belimumab versus placebo, plus standard systemic lupus erythematosus (SLE) therapy, on organ domain-specific SLE disease activity. METHODS: Data obtained after 52 weeks of treatment from two phase III trials (BLISS-52 and BLISS-76) comparing belimumab 1 and 10 mg/kg versus placebo, plus standard therapy, in 1684 autoantibody-positive patients were analysed post hoc for changes in British Isles Lupus Assessment Group (BILAG) and Safety of Estrogens in Lupus National Assessment-Systemic Lupus Erythematosus Disease Activity Index (SELENA-SLEDAI) organ domain scores. RESULTS: At baseline, the domains involved in the majority of patients were musculoskeletal and mucocutaneous by both BILAG and SELENA-SLEDAI, and immunological by SELENA-SLEDAI. At 52 weeks, significantly more patients treated with belimumab versus placebo had improvement in BILAG musculoskeletal and mucocutaneous domains (1 and 10 mg/kg), and in SELENA-SLEDAI mucocutaneous (10 mg/kg), musculoskeletal (1 mg/kg) and immunological (1 and 10 mg/kg) domains. Improvement was also observed in other organ systems with a low prevalence (≤16%) at baseline, including the SELENA-SLEDAI vasculitis and central nervous system domains. Significantly fewer patients treated with belimumab versus placebo had worsening in the BILAG haematological domain (1 mg/kg) and in the SELENA-SLEDAI immunological (10 mg/kg), haematological (10 mg/kg) and renal (1 mg/kg) domains. CONCLUSIONS: Belimumab treatment improved overall SLE disease activity in the most common musculoskeletal and mucocutaneous organ domains. Less worsening occurred in the haematological, immunological and renal domains.

Association of genetic variants in complement factor H and factor H-related genes with systemic lupus erythematosus susceptibility.

Systemic lupus erythematosus (SLE), a complex polygenic autoimmune disease, is associated with increased complement activation. Variants of genes encoding complement regulator factor H (CFH) and five CFH-related proteins (CFHR1-CFHR5) within the chromosome 1q32 locus linked to SLE, have been associated with multiple human diseases and may contribute to dysregulated complement activation predisposing to SLE. We assessed 60 SNPs covering the CFH-CFHRs region for association with SLE in 15,864 case-control subjects derived from four ethnic groups. Significant allelic associations with SLE were detected in European Americans (EA) and African Americans (AA), which could be attributed to an intronic CFH SNP (rs6677604, in intron 11, P(meta) = 6.6×10(-8), OR = 1.18) and an intergenic SNP between CFHR1 and CFHR4 (rs16840639, P(meta) = 2.9×10(-7), OR = 1.17) rather than to previously identified disease-associated CFH exonic SNPs, including I62V, Y402H, A474A, and D936E. In addition, allelic association of rs6677604 with SLE was subsequently confirmed in Asians (AS). Haplotype analysis revealed that the underlying causal variant, tagged by rs6677604 and rs16840639, was localized to a ~146 kb block extending from intron 9 of CFH to downstream of CFHR1. Within this block, the deletion of CFHR3 and CFHR1 (CFHR3-1Δ), a likely causal variant measured using multiplex ligation-dependent probe amplification, was tagged by rs6677604 in EA and AS and rs16840639 in AA, respectively. Deduced from genotypic associations of tag SNPs in EA, AA, and AS, homozygous deletion of CFHR3-1Δ (P(meta) = 3.2×10(-7), OR = 1.47) conferred a higher risk of SLE than heterozygous deletion (P(meta) = 3.5×10(-4), OR = 1.14). These results suggested that the CFHR3-1Δ deletion within the SLE-associated block, but not the previously described exonic SNPs of CFH, might contribute to the development of SLE in EA, AA, and AS, providing new insights into the role of complement regulators in the pathogenesis of SLE.

Efficacy and safety of belimumab in patients with active systemic lupus erythematosus: a randomised, placebo-controlled, phase 3 trial.

BACKGROUND: Systemic lupus erythematosus is a heterogeneous autoimmune disease that is associated with B-cell hyperactivity, autoantibodies, and increased concentrations of B-lymphocyte stimulator (BLyS). The efficacy and safety of the fully human monoclonal antibody belimumab (BLyS-specific inhibitor) was assessed in patients with active systemic lupus erythematosus. METHODS: Patients (aged ≥18 years) who were seropositive with scores of at least 6 on the Safety of Estrogens in Lupus Erythematosus National Assessment-Systemic Lupus Erythematosus Disease Activity Index (SELENA-SLEDAI) were enrolled in a multicentre phase 3 study, which was done in Latin America, Asia-Pacific, and eastern Europe. Patients were randomly assigned by use of a central interactive voice response system in a 1:1:1 ratio to belimumab 1 mg/kg or 10 mg/kg, or placebo by intravenous infusion in 1 h on days 0, 14, and 28, and then every 28 days until 48 weeks, with standard of care. Patients, investigators, study coordinators, and sponsors were masked to treatment assignment. Primary efficacy endpoint was improvement in the Systemic Lupus Erythematosus Responder Index (SRI) at week 52 (reduction ≥4 points in SELENA-SLEDAI score; no new British Isles Lupus Assessment Group [BILAG] A organ domain score and no more than 1 new B organ domain score; and no worsening [<0·3 increase] in Physician's Global Assessment [PGA] score) versus baseline. Method of analysis was by modified intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00424476. FINDINGS: 867 patients were randomly assigned to belimumab 1 mg/kg (n=289) or 10 mg/kg (n=290), or placebo (n=288). 865 were treated and analysed in the belimumab (1 mg/kg, n=288; 10 mg/kg, n=290) and placebo groups (n=287). Significantly higher SRI rates were noted with belimumab 1 mg/kg (148 [51%], odds ratio 1·55 [95% CI 1·10-2·19]; p=0·0129) and 10 mg/kg (167 [58%], 1·83 [1·30-2·59]; p=0·0006) than with placebo (125 [44%]) at week 52. More patients had their SELENA-SLEDAI score reduced by at least 4 points during 52 weeks with belimumab 1 mg/kg (153 [53%], 1·51 [1·07-2·14]; p=0·0189) and 10 mg/kg (169 [58%], 1·71 [1·21-2·41]; p=0·0024) than with placebo (132 [46%]). More patients given belimumab 1 mg/kg (226 [78%], 1·38 [0·93-2·04]; p=0·1064) and 10 mg/kg (236 [81%], 1·62 [1·09-2·42]; p=0·0181) had no new BILAG A or no more than 1 new B flare than did those in the placebo group (210 [73%]). No worsening in PGA score was noted in more patients with belimumab 1 mg/kg (227 [79%], 1·68 [1·15-2·47]; p=0·0078) and 10 mg/kg (231 [80%], 1·74 [1·18-2·55]; p=0·0048) than with placebo (199 [69%]). Rates of adverse events were similar in the groups given belimumab 1 mg/kg and 10 mg/kg, and placebo: serious infection was reported in 22 (8%), 13 (4%), and 17 (6%) patients, respectively, and severe or serious hypersensitivity reactions on an infusion day were reported in two (<1%), two (<1%), and no patients, respectively. No malignant diseases were reported. INTERPRETATION: Belimumab has the potential to be the first targeted biological treatment that is approved specifically for systemic lupus erythematosus, providing a new option for the management of this important prototypic autoimmune disease. FUNDING: Human Genome Sciences and GlaxoSmithKline.

Association of a functional variant downstream of TNFAIP3 with systemic lupus erythematosus.

Systemic lupus erythematosus (SLE, MIM152700) is an autoimmune disease characterized by self-reactive antibodies resulting in systemic inflammation and organ failure. TNFAIP3, encoding the ubiquitin-modifying enzyme A20, is an established susceptibility locus for SLE. By fine mapping and genomic re-sequencing in ethnically diverse populations, we fully characterized the TNFAIP3 risk haplotype and identified a TT>A polymorphic dinucleotide (deletion T followed by a T to A transversion) associated with SLE in subjects of European (P = 1.58 × 10(-8), odds ratio = 1.70) and Korean (P = 8.33 × 10(-10), odds ratio = 2.54) ancestry. This variant, located in a region of high conservation and regulatory potential, bound a nuclear protein complex composed of NF-κB subunits with reduced avidity. Further, compared with the non-risk haplotype, the haplotype carrying this variant resulted in reduced TNFAIP3 mRNA and A20 protein expression. These results establish this TT>A variant as the most likely functional polymorphism responsible for the association between TNFAIP3 and SLE.

Identification of a systemic lupus erythematosus susceptibility locus at 11p13 between PDHX and CD44 in a multiethnic study.

Systemic lupus erythematosus (SLE) is considered to be the prototypic autoimmune disease, with a complex genetic architecture influenced by environmental factors. We sought to replicate a putative association at 11p13 not yet exceeding genome-wide significance (p < 5 × 10(-8)) identified in a genome-wide association study (GWAS). Our GWA scan identified two intergenic SNPs located between PDHX and CD44 showing suggestive evidence of association with SLE in cases of European descent (rs2732552, p = 0.004, odds ratio [OR] = 0.78; rs387619, p = 0.003, OR = 0.78). The replication cohort consisted of >15,000 subjects, including 3562 SLE cases and 3491 controls of European ancestry, 1527 cases and 1811 controls of African American (AA) descent, and 1265 cases and 1260 controls of Asian origin. We observed robust association at both rs2732552 (p = 9.03 × 10(-8), OR = 0.83) and rs387619 (p = 7.7 × 10(-7), OR = 0.83) in the European samples with p(meta) = 1.82 × 10(-9) for rs2732552. The AA and Asian SLE cases also demonstrated association at rs2732552 (p = 5 × 10(-3), OR = 0.81 and p = 4.3 × 10(-4), OR = 0.80, respectively). A meta-analysis of rs2732552 for all racial and ethnic groups studied produced p(meta) = 2.36 × 10(-13). This locus contains multiple regulatory sites that could potentially affect expression and functions of CD44, a cell-surface glycoprotein influencing immunologic, inflammatory, and oncologic phenotypes, or PDHX, a subunit of the pyruvate dehydrogenase complex.