Search

OBJECTIVE: This study was undertaken to characterize kidney and urine antibody-secreting cells (ASCs) from patients with active lupus nephritis, before and after induction therapy. METHODS: We included patients with biopsy-proven active lupus nephritis and performed anti-CD138 staining of kidney biopsy samples to visualize ASCs. We performed single-cell gene expression profiling on sorted ASCs from fresh biopsy samples using multiplex reverse transcriptase-polymerase chain reaction. We used a gene set that allowed for the study of ASC maturation from plasmablasts to long-lived plasma cells. We quantified urine ASCs from untreated patients with lupus nephritis at diagnosis and after 6 months of prospective follow-up during induction therapy. RESULTS: The number of kidney CD138+ ASCs in 46 untreated patients with lupus nephritis was correlated with a low estimated glomerular filtration rate and with tubulointerstitial damage. Most kidney ASCs from 3 untreated patients had a plasmablast molecular signature; in contrast, in 4 patients with refractory lupus nephritis, the kidney ASCs were mainly long-lived plasma cells, representing an ASC transcriptional profile similar to that in the bone marrow of 2 healthy donors. Some urine ASCs with a plasmablast signature were detected in patients with untreated active lupus nephritis. The presence of urine ASCs at 6 months was associated with treatment failure. CONCLUSION: Our results suggest potential for ASC-directed therapy in refractory lupus nephritis.

Purpose To investigate the diagnostic performance of sacroiliac joint (SIJ) magnetic resonance imaging (MRI) and the incremental value of spine MRI to “predict” clinical disease activity in patients with axial spondyloarthritis (axSpA). Materials and methods This cross-sectional study included adult patients with known axSpA according to the SpondyloArthritis International Society (ASAS) classification criteria, radiological arm. MRI disease activity was scored semi-quantitatively for SIJ and total spine MRI in each patient. Two cut-off levels (≥ 1.3 and ≥ 2.1) for ankylosing spondylitis disease activity score with C-reactive protein (ASDAS-CRP) were considered for clinical disease activity categorization. MRI scores were first evaluated individually. Then, SIJ score was combined with the score from a spine segment (lumbar, cervical, thoracic or total spine) to build a bi-parametric model using a classification tree. Receiver operating characteristic (ROC) curves were constructed to evaluate the classification performance according to disease activity category of these models. Results Forty-four patients (30 men, 14 women; mean age, 37 years ± 10 [SD] [range: 17–64 years]) with a mean disease duration of 5 years ± 8 (SD) (range: 0–35 years) were included. Thirty-six patients (36/44; 82%) had ASDAS-CRP ≥ 1.3 and 27 patients (27/44; 61%) had ASDAS-CRP ≥ 2.1. The most frequently involved spinal segment was mid-thoracic (T7-T8). The SIJ MRI score was an informative model to identify active axSpA (AUC ≥ 0.7, regardless of the cut-off level on ASDAS-CRP). Performance of bi-parametric models based on “SIJ + thoracic spine” (for detecting patients with ASDAS-CRP ≥ 1.3) or “SIJ + total spine” (for detecting patients with ASDAS-CRP ≥ 2.1) outperformed that of the individual SIJ score (P Conclusion The combination of MRI of the SIJ and spine allows to accurately discriminate between active and inactive axSpA, outperforming SIJ MRI alone.

BACKGROUND: Although targeted biological treatments have transformed the outlook for patients with rheumatoid arthritis, 40% of patients show poor clinical response, which is mechanistically still unexplained. Because more than 50% of patients with rheumatoid arthritis have low or absent CD20 B cells-the target for rituximab-in the main disease tissue (joint synovium), we hypothesised that, in these patients, the IL-6 receptor inhibitor tocilizumab would be more effective. The aim of this trial was to compare the effect of tocilizumab with rituximab in patients with rheumatoid arthritis who had an inadequate response to anti-tumour necrosis factor (TNF) stratified for synovial B-cell status. METHODS: This study was a 48-week, biopsy-driven, multicentre, open-label, phase 4 randomised controlled trial (rituximab vs tocilizumab in anti-TNF inadequate responder patients with rheumatoid arthritis; R4RA) done in 19 centres across five European countries (the UK, Belgium, Italy, Portugal, and Spain). Patients aged 18 years or older who fulfilled the 2010 American College of Rheumatology and European League Against Rheumatism classification criteria for rheumatoid arthritis and were eligible for treatment with rituximab therapy according to UK National Institute for Health and Care Excellence guidelines were eligible for inclusion in the trial. To inform balanced stratification, following a baseline synovial biopsy, patients were classified histologically as B-cell poor or rich. Patients were then randomly assigned (1:1) centrally in block sizes of six and four to receive two 1000 mg rituximab infusions at an interval of 2 weeks (rituximab group) or 8 mg/kg tocilizumab infusions at 4-week intervals (tocilizumab group). To enhance the accuracy of the stratification of B-cell poor and B-cell rich patients, baseline synovial biopsies from all participants were subjected to RNA sequencing and reclassified by B-cell molecular signature. The study was powered to test the superiority of tocilizumab over rituximab in the B-cell poor population at 16 weeks. The primary endpoint was defined as a 50% improvement in Clinical Disease Activity Index (CDAI50%) from baseline. The trial is registered on the ISRCTN database, ISRCTN97443826, and EudraCT, 2012-002535-28. FINDINGS: Between Feb 28, 2013, and Jan 17, 2019, 164 patients were classified histologically and were randomly assigned to the rituximab group (83 [51%]) or the tocilizumab group (81 [49%]). In patients histologically classified as B-cell poor, there was no statistically significant difference in CDAI50% between the rituximab group (17 [45%] of 38 patients) and the tocilizumab group (23 [56%] of 41 patients; difference 11% [95% CI -11 to 33], p=0·31). However, in the synovial biopsies classified as B-cell poor with RNA sequencing the tocilizumab group had a significantly higher response rate compared with the rituximab group for CDAI50% (rituximab group 12 [36%] of 33 patients vs tocilizumab group 20 [63%] of 32 patients; difference 26% [2 to 50], p=0·035). Occurrence of adverse events (rituximab group 76 [70%] of 108 patients vs tocilizumab group 94 [80%] of 117 patients; difference 10% [-1 to 21) and serious adverse events (rituximab group 8 [7%] of 108 vs tocilizumab group 12 [10%] of 117; difference 3% [-5 to 10]) were not significantly different between treatment groups. INTERPRETATION: The results suggest that RNA sequencing-based stratification of rheumatoid arthritis synovial tissue showed stronger associations with clinical responses compared with histopathological classification. Additionally, for patients with low or absent B-cell lineage expression signature in synovial tissue tocilizumab is more effective than rituximab. Replication of the results and validation of the RNA sequencing-based classification in independent cohorts is required before making treatment recommendations for clinical practice. FUNDING: Efficacy and Mechanism Evaluation programme from the UK National Institute for Health Research. ispartof: LANCET vol:397 issue:10271 pages:305-317 ispartof: location:England status: published

OBJECTIVE: To evaluate the long-term efficacy and safety of canakinumab and explore prediction of response in patients with systemic juvenile idiopathic arthritis (JIA) with or without fever at treatment initiation. METHODS: At enrollment, patients with active systemic JIA (ages 2 to

We herein report two new adolescent cases of Bier anemic spots, cyanosis, and urticaria-like eruption (BASCULE) syndrome. This rare, recently described condition may be associated with postural orthostatic tachycardia syndrome (POTS) and other forms of orthostatic intolerance. This report provides details on two cases and a literature review.

ObjectivesBecause a significant fraction of patients with lupus nephritis (LN) develops renal impairment, there is a need to better understand the mechanisms underlying disease progression. Here, we assessed for cellular senescence in the LN kidney, and its association with disease severity and outcome.MethodsWe enumerated the number of cells positive for p16INK4a protein, a marker of cellular senescence, by immunohistochemistry followed by digital quantification, on renal biopsies from 40 patients with active LN. We tested for an association of p16INK4a with renal fibrosis, CD8+ T cell infiltration, systemic disease and renal function at baseline and at 5 years.ResultsThe presence of p16INK4a-positive cells was significantly associated with lower estimated glomerular filtration rate at baseline and 5 years post-treatment, independently of patient demographics and systemic disease parameters. It was also associated with higher baseline renal fibrosis and CD8+ T cell infiltration. Interestingly, we observed marked spatial co-distribution of glomerular p16INK4a-positive cells with CD8+ T cells.ConclusionWe demonstrate, for the first time, that LN biopsies characterised by renal impairment display increased p16INK4a-positive cells, associated with higher fibrosis and CD8+ T cell infiltration. Cellular senescence may represent a kidney-intrinsic disease mechanism and potentially, a novel therapeutic target in LN.

ObjectivesOur goal was to assess for the histological and transcriptomic effects of abatacept on RA synovia, and to compare them with previously published data from four other DMARDs: tocilizumab, rituximab, methotrexate, and adalimumab.MethodsSynovial tissue was obtained using ultrasound-guided biopsy from affected joints of 14 patients, before and 16 weeks after treatment with subcutaneous abatacept 125 mg weekly. Paraffin-sections were stained and scored for CD3+, CD20+, and CD68+ cell infiltration. Transcriptional profiling was performed using GeneChip Human Genome U133 Plus 2.0 arrays (Affymetrix) and analyzed on Genespring GX (Agilent). Pathway analyses were performed on Genespring GX, Metascape, and EnrichR.ResultsGene expression analysis identified 304 transcripts modulated by abatacept in synovial tissue. Downregulated genes were significantly enriched for immune processes, strongly overlapping with our findings on other therapies. Data were pooled across these studies, revealing that genes downregulated by DMARDs are significantly enriched for both T-cell and myeloid leukocyte activation pathways. Interestingly, DMARDs seem to have coordinate effects on the two pathways, with a stronger impact in good responders to therapy as compared to moderate and non-responders.ConclusionWe provide evidence that the effects of five DMARDs on the RA synovium culminate in the same pathways. This confirms previous studies suggesting the existence of common mediators downstream of DMARDs, independent of their primary targets.

Objectives Because a significant fraction of patients with lupus nephritis (LN) develops renal impairment, there is a need to better understand the mechanisms underlying disease progression. Here, we assessed for cellular senescence in the LN kidney, and its association with disease severity and outcome. Methods We enumerated the number of cells positive for p16INK4a protein, a marker of cellular senescence, by immunohistochemistry followed by digital quantification, on renal biopsies from 40 patients with active LN. We tested for an association of p16INK4a with renal fibrosis, CD8+ T cell infiltration, systemic disease and renal function at baseline and at 5 years. Results The presence of p16INK4a-positive cells was significantly associated with lower estimated glomerular filtration rate at baseline and 5 years post-treatment, independently of patient demographics and systemic disease parameters. It was also associated with higher baseline renal fibrosis and CD8+ T cell infiltration. Interestingly, we observed marked spatial co-distribution of glomerular p16INK4a-positive cells with CD8+ T cells. Conclusion We demonstrate, for the first time, that LN biopsies characterised by renal impairment display increased p16INK4a-positive cells, associated with higher fibrosis and CD8+ T cell infiltration. Cellular senescence may represent a kidney-intrinsic disease mechanism and potentially, a novel therapeutic target in LN.

OBJECTIVE: Clinical heterogeneity, a hallmark of systemic autoimmune diseases, impedes early diagnosis and effective treatment, issues that may be addressed if patients could be classified into groups defined by molecular pattern. This study was undertaken to identify molecular clusters for reclassifying systemic autoimmune diseases independently of clinical diagnosis. METHODS: Unsupervised clustering of integrated whole blood transcriptome and methylome cross-sectional data on 955 patients with 7 systemic autoimmune diseases and 267 healthy controls was undertaken. In addition, an inception cohort was prospectively followed up for 6 or 14 months to validate the results and analyze whether or not cluster assignment changed over time. RESULTS: Four clusters were identified and validated. Three were pathologic, representing "inflammatory," "lymphoid," and "interferon" patterns. Each included all diagnoses and was defined by genetic, clinical, serologic, and cellular features. A fourth cluster with no specific molecular pattern was associated with low disease activity and included healthy controls. A longitudinal and independent inception cohort showed a relapse-remission pattern, where patients remained in their pathologic cluster, moving only to the healthy one, thus showing that the molecular clusters remained stable over time and that single pathogenic molecular signatures characterized each individual patient. CONCLUSION: Patients with systemic autoimmune diseases can be jointly stratified into 3 stable disease clusters with specific molecular patterns differentiating different molecular disease mechanisms. These results have important implications for future clinical trials and the study of nonresponse to therapy, marking a paradigm shift in our view of systemic autoimmune diseases. ispartof: ARTHRITIS & RHEUMATOLOGY vol:73 issue:6 pages:1073-1085 ispartof: location:United States status: published

IntroductionJuvenile idiopathic arthritis (JIA) represents a very heterogeneous disease. As such, it has been a challenge to describe the disease activity of JIA cohorts. Our objective was to describe the first Belgian cohort of children with JIA by assessing their disease characteristics, outcomes, and potential markers of prognosis.MethodsThe CAP48 cohort is a multicentric observational study of children with recent or well-established diagnosis of JIA (naïve or not to treatment at baseline), evaluated every 3 to 6 months during a follow-up of 10 years.ResultsThere were 125 children included, composing of 25 naïve and 100 established patients. Their median age at onset was 6.2 and 4.2 years in the naïve and established cohort respectively, with a predominance of female. All subtypes of JIA were represented in both cohorts. The mean DAS28-CRP and JADAS10-CRP at baseline in naïve patients was 2.52 and 6.0 respectively. Uveitis occurred in 19% of patients and was strongly associated with presence of antinuclear antibodies (odds ratio of 6). Among naïve patients, 55% were in remission at 12 months according to ACR criteria and JADAS10 scores, in contrast with 100% achieving DAS28 remission. ConclusionThis first cohort study in Belgium allowed to compare its data to other existing cohorts and to evaluate quality of care in Belgian French-speaking hospitals. Additionally, it highlighted a superiority of JADAS10 over DAS28 to monitor and evaluate remission in JIA. This study also underlined a need for more accurate markers of prognosis to improve treatment and long-term outcomes.

DEAR EDITOR, The feasibility of testing multiple genes at once using Next Generation Sequencing, particularly Whole Exome Sequencing (WES), has expanded the phenotypic spectrum associated with many disease genes. Distinguishing atypical presentation from combined gene effects and incidental from causal findings can however be challenging, particularly when composite phenotypes are themselves extremely rare. [...]

Introduction In the management of juvenile idiopathic arthritis (JIA), there is a lack of diagnostic and prognostic biomarkers. This study assesses the use of serum calprotectin (sCal) as a marker to monitor disease activity, and as a classification and prognosis tool of response to treatment or risk of flares in patients with JIA. Methods Eighty-one patients with JIA from the CAP48 multicentric cohort were included in this study, as well as 11 non-paediatric healthy controls. An ELISA method was used to quantify sCal with a commercial kit. Results Patients with an active disease compared with healthy controls and with patients with inactive disease showed an eightfold and a twofold increased level of sCal, respectively. sCal was found to be correlated with the C-reactive protein (CRP) and even more strongly with the erythrocyte sedimentation rate. Evolution of DAS28 scores correlated well with evolution of sCal, as opposed to evolution of CRP. With regard to CRP, sCal could differentiate forms with active oligoarthritis from polyarthritis and systemic forms. However, sCal brought an added value compared with the CRP as a prognosis marker. Indeed, patients with active disease and reaching minimal disease activity (according to Juvenile Arthritis Disease Activity Score) at 6 months following the test had higher sCal levels, while patients with inactive disease had higher sCal levels if a flare was observed up to 3–9 months following the test. Conclusions This study confirms the potential uses of sCal as a biomarker in the diagnosis and follow-up of JIA.

Background The International Consensus on Antinuclear Antibody (ANA) Patterns (ICAP) has recently proposed nomenclature in order to harmonize ANA indirect immunofluorescence (IIF) pattern reporting. ICAP distinguishes competent-level from expert-level patterns. A survey was organized to evaluate reporting, familiarity, and considered clinical value of ANA IIF patterns. Methods Two surveys were distributed by European Autoimmunity Standardization Initiative (EASI) working groups, the International Consensus on ANA Patterns (ICAP) and UK NEQAS to laboratory professionals and clinicians. Results 438 laboratory professionals and 248 clinicians from 67 countries responded. Except for dense fine speckled (DFS), the nuclear competent patterns were reported by > 85% of the laboratories. Except for rods and rings, the cytoplasmic competent patterns were reported by > 72% of laboratories. Cytoplasmic IIF staining was considered ANA positive by 55% of clinicians and 62% of laboratory professionals, with geographical and expertise-related differences. Quantification of fluorescence intensity was considered clinically relevant for nuclear patterns, but less so for cytoplasmic and mitotic patterns. Combining IIF with specific extractable nuclear antigens (ENA)/dsDNA antibody testing was considered most informative. Of the nuclear competent patterns, the centromere and homogeneous pattern obtained the highest scores for clinical relevance and the DFS pattern the lowest. Of the cytoplasmic patterns, the reticular/mitochondria-like pattern obtained the highest scores for clinical relevance and the polar/Golgi-like and rods and rings patterns the lowest. Conclusion This survey confirms that the major nuclear and cytoplasmic ANA IIF patterns are considered clinically important. There is no unanimity on classifying DFS, rods and rings and polar/Golgi-like as a competent pattern and on reporting cytoplasmic patterns as ANA IIF positive.

BackgroundThe International Consensus on Antinuclear Antibody (ANA) Patterns (ICAP) has recently proposed nomenclature in order to harmonize ANA indirect immunofluorescence (IIF) pattern reporting. ICAP distinguishes competent-level from expert-level patterns. A survey was organized to evaluate reporting, familiarity, and considered clinical value of ANA IIF patterns. MethodsTwo surveys were distributed by European Autoimmunity Standardization Initiative (EASI) working groups, the International Consensus on ANA Patterns (ICAP) and UK NEQAS to laboratory professionals and clinicians. Results438 laboratory professionals and 248 clinicians from 67 countries responded. Except for dense fine speckled (DFS), the nuclear competent patterns were reported by >85% of the laboratories. Except for rods and rings, the cytoplasmic competent patterns were reported by >72% of laboratories. Cytoplasmic IIF staining was considered ANA positive by 55% of clinicians and 62% of laboratory professionals, with geographical and expertise-related differences. Quantification of fluorescence intensity was considered clinically relevant for nuclear patterns, but less so for cytoplasmic and mitotic patterns. Combining IIF with specific extractable nuclear antigens (ENA)/dsDNA antibody testing was considered most informative. Of the nuclear competent patterns, the centromere and homogeneous pattern obtained the highest scores for clinical relevance and the DFS pattern the lowest. Of the cytoplasmic patterns, the reticular/mitochondria-like pattern obtained the highest scores for clinical relevance and the polar/Golgi-like and rods and rings patterns the lowest. ConclusionThis survey confirms that the major nuclear and cytoplasmic ANA IIF patterns are considered clinically important. There is no unanimity on classifying DFS, rods and rings and polar/Golgi-like as a competent pattern and on reporting cytoplasmic patterns as ANA IIF positive.

Background/purpose Studies have demonstrated that rheumatoid arthritis (RA) patients who achieve low disease activity or remission are able to taper biological disease-modifying antirheumatic drugs (bDMARDs). The aim of this study was to evaluate the proportion of patients in whom bDMARDs can be tapered in daily practice and to analyse the characteristics of these patients. Other objectives were to analyse which bDMARDs are more suitable for dose reduction and the cost savings. Results Data from 332 eligible RA patients from our Brussels UCLouvain cohort were retrospectively analysed; 140 patients (42.1%) received a tapered regimen, and 192 received stable doses of bDMARDs. The age at diagnosis (43.1 vs 38.7 years, p = 0.04), health assessment questionnaire (HAQ) score (1.3 vs 1.5, p = 0.048), RF positivity rate (83.3 vs 72.9%, p = 0.04) and disease duration at the time of bDMARD introduction (9.7 vs 12.1 years, p = 0.034) were significantly different between the reduced-dose and stable-dose groups. Interestingly, relatively more patients receiving a tapered dose were treated with a combination of bDMARDs and methotrexate (MTX) (86.7% vs 73.8%, p = 0.005). In our cohort, anti-TNF agents were the most commonly prescribed medications (68%). Only 15 patients experienced a flare during follow-up. Adalimumab, etanercept and rituximab were the most common bDMARDs in the reduced-dose group and were associated with the most important reductions in annual cost. Conclusion In daily practice, tapering bDMARDs in RA patients who have achieved low disease activity or remission is an achievable goal in a large proportion of patients, thereby reducing potential side effects and annual drug-associated costs. The combination of bDMARDs with MTX could improve the success of dose reduction attempts. Trial registration This retrospective non-interventional study was retrospectively registered with local ethics approval.

Background Biologic therapies have transformed the outlook for RA but the significant health economic impact of these therapies has highlighted the need to define predictive markers of response. Rituximab (RTX) is licensed for use following failure of csDMARDs and TNF inhibitor (TNFi) therapy. However, in this increasing therapeutically resistant cohort only 30% of patients achieve an ACR50 response. The observation in early RA that 50% of patients show low/absence of synovial B-cells prompted us to test the hypothesis that in these patients a biologic agent targeting alternative pathways maybe more effective. We report results from the first pathobiology-driven randomised controlled trial (RCT) in RA (R4RA) evaluating whether patient stratification according to the synovial B-cell rich/poor status enriches for response/non response to RTX. Methods R4RA is a phase IV open-label RCT conducted in 19 European centres recruiting patients failing or intolerant to csDMARD therapy and at least one TNFi. Synovial tissue was obtained at trial entry and used to classify patients as B-cell rich or poor using both histological and RNA-seq classification criteria. Patients were randomised to receive RTX or tocilizumab (TCZ). The study was powered to test in the B cell poor population superiority of TCZ over RTX at 16 weeks. The primary and co-primary end-points were defined respectively as Clinical Disease Activity Index (CDAI) ≥50% improvement from baseline and Major Treatment response (MTR)= CDAI improvement ≥ 50% and CDAI ≤10.1. Results The trial recruited to target (n = 164) with a power of 89.5%. In the B cell poor cohort a numerically higher number of patients achieved the primary endpoint and a significantly higher number of patients achieved co-primary endpoint (MTR). Classification of patients as B cell poor/rich according to RNA-seq criteria enhanced the difference between TCZ and RTX, with a significantly higher number of TCZ treated patients reaching both CDAI 50% improvement and CDAI MTR in the B-cell poor group. Conclusion In a RA B cell poor population failing csDMARDs and TNFi therapy, TCZ is more effective than RTX. This first biopsy-driven RCT suggests clinical utility for integrating molecular pathology profiling into treatment algorithms to allocate targeted therapies. Disclosures F. Humby: Honoraria; Roche, Pfizer. Grants/research support; Pfizer. P. Durez: BMS,Bristol-Myers Squibb, Celltrion, Eli Lilly, Hospira, Mundipharma, Pfizer, Samsung, Sanofi, UCB. M. Buch: Consultancies; Pfizer, Roche, UCB, AbbVie, Eli Lilly, Sandoz, and Sanofi. Grants/research support; Pfizer, Roche, UCB, AbbVie, Eli Lilly, Sandoz, and Sanofi. M. Lewis: None. M. Bombardieri: None. H. Rizvi: None. S. Kelly: None. L. Fossati: None. R. Hands: None. G. Giorli: None. A. Mahto: None. C. Montecucco: None. B. Lauwerys: None. V.C. Romao: None. A.G. Pratt: Member of speakers’ bureau; Eli Lilly and Janssen-Cilag Ltd. Grants/research support; Pfizer. S. Bugatti: None. N. Ng: None. F. Rivellese: None. P. Ho: None. M. Bellan: None. P. Sainaghi: None. P. Verschueren: None. N. Gendi: None. B. Dasgupta: Abbvie, BMS, GSK, Roche, Roche Chugai, Sanofi, Sanofi Aventis, Sanofi-Aventis. A. Cauli: BMS, Celgene, Lilly, Lilly MSD, MSD, Novartis, Pfizer, Sanofi, Sigma Wesseumen, UCB. C. John: None. A. Nerviani: None. G. Thornborn: None. D. Holroyd: None. M. Congia: None. C. Thompson: None. P. Reynolds: None. J. Cañete: None. R. J. Moots: Biogen, Bristol-Myers Squibb, Chugai, Novartis, Pfizer Inc, Roche, Sandoz, UCB. P.C. Taylor: AbbVie, Biogen, Celgene, Eli Lilly and Company, Fresenius, Fresenius SE & Co, Galapagos, Gilead. GlaxoSmithKline, Janssen, Lilly, Nordic Pharma, Pfizer, Pfizer Inc, Roche, Sanofi, UCB. C. Edwards: Abbvie, Biogen, BMS, Fresenius, Janssen, Lilly, MSD, Novartis, Pfizer, Roche, UCB. J. Isaacs: None. P. Sasieni: None. J. E. Fonesca: None. E. Choy: AbbVie, Abbvie, Roche, Chugai, Amgen, Eli Lilly, Janssen, Novartis, Regeneron, R-Pharm and Sanofi, Amgen, Amgen, Roche, Chugai, Bristol-Myers Squibb, Eli-Lilly Janssen, Pfizer, Regeneron, Sanofi and UCB., AstraZeneca, Bio-Cancer, Bio-Cancer, Biogen, Novartis, Sanofi, Roche, Pfizer and UCB ,Biogen, BMS, Boehringer Ingelheim, Celgene, Chugai Pharma, Eli Lilly, Ferring Pharmaceuticals, GSK, Hospira, Janssen, Jazz Pharmaceuticals, Merck Sharp & Dohme, Merrimack Pharmaceutical, Napp, Novartis, Novimmune, ObsEva, Pfizer, Regeneron, Roche, R-Pharm, Sanofi, SynAct Pharma, Tonix, Union Chimique Belge. C. Pitzalis: None. NIHR have funded the study.

Background Renal fibrosis is a feared complication of Lupus Nephritis (LN), and is associated with irreversible loss of kidney function. In our previous experiments, we found that intrarenal infiltration by immune effectors in LN correlates with the development of renal fibrosis. Here, we wondered whether cellular senescence, through its typical secretome (known as senescence-associated secretory phenotype or SASP) or through the accumulation of functionally incompetent cells, are part of the renal functional impairment and fibrotic process in LN. Methods Microarray data (Illumina HumanHT-2 v4 Expression BeadChip), obtained by our group from 32 human LN kidney biopsies and 8 controls were mined using GeneSpring software in order to study the expression of SASP-associated transcripts. Senescent cells were identified in human LN kidney biopsies using an anti-p16 antibody (Roche Diagnostics). Evaluation of glomerular activity and chronicity indices, glomerular and interstitial fibrosis was performed using conventional or quantitative scores on HE- PAS- and Red Sirius-stained sections. Clinical and biological data were retrieved from the medical files of the patients. Results Mining of microarray data obtained from 32 LN kidney biopsies indicated that SASP-associated transcripts (e.g. IGFB4, VCAM1, TGFb2, COL1A2, MMP7) were significantly overexpressed in kidney biopsies characterized by the presence of adaptive immune cell infiltrates in the interstitium and lower renal function. Expression of SASP-associated transcripts correlated significantly with the expression of b galactosidase (GLB1), a key regulator of the senescence process. In a pilot experiment, we stained LN renal biopsy sections using anti-p16 antibodies, in order to detect the presence of senescent cells. We found a positive stain in podocytes and renal tubular cells from 8 LN patients. The number of positive cells correlated positively with the number of intrarenal CD8-positive cells and the amount of fibrosis in these samples, while it correlated negatively with renal function (eGFR). Conclusion Our data show that the presence of senescent podocytes and renal tubular cells in LN kidney biopsies correlates with fibrotic changes and impaired renal function. Characterization of senescent cells in a larger cohort of LN biopsies is ongoing. Our observations are in line with the hypothesis that inflammation-accelerated senescence links the presence of activated adaptive immune effectors in the lupus kidney and the development of fibrosis.

Background/Purpose Pathogenic antibody-secreting cells (ASC) are poorly characterized in human lupus nephritis (LN). Our objective was to compare the single cell molecular signature of ASC in kidney and urine from patients with active LN, either untreated or after immunosuppressive therapy failure. Methods ASC were identified by anti-CD138 staining on fixed renal biopsies from patients with active LN. We sorted single-ASC from fresh renal biopsies to perform gene expression profiling. ASC transcriptional program from urine of untreated LN patients was assessed at diagnosis and after a prospective follow up during induction therapy. Results Interstitial infiltrates of CD138+ ASC were found in untreated (N=15) and refractory patients (N=6). Single cell molecular signature of kidney ASC from untreated patients revealed that these cells were mostly plasmablasts and contrasted with ASC signature from patients with mycophenolate mofetil failure that expressed long-lived plasma cells genes and clustered with long-lived bone marrow ASC from healthy donors. A plasmablast signature was observed in urine ASC at diagnosis, similar to their kidney counterpart. The concentration of urine ASC from 22 untreated patients correlated with ISN/RPS classification, with higher concentration in class IV patients (p Conclusion These results suggest that plasmablasts infiltrate kidney of untreated LN patients, while kidney long-lived ASC may contribute to the failure of immunosuppressive therapy. Acknowledgement This work was funded by FOREUM.

Objective: Reliable non-invasive biomarkers are needed to assess disease activity and prognosis in patients with systemic lupus erythematosus (SLE). Glycoprotein acetylation (GlycA), a novel biomarker for chronic inflammation, has been reported to be increased in several inflammatory diseases. We investigated the relevance of serum GlycA in SLE patients exhibiting various levels of activity and severity, especially with regards to renal involvement. Methods: Serum GlycA was measured by nuclear magnetic resonance spectroscopy in samples from well characterized SLE patients and from both healthy controls and patients with other kidney diseases (KD). Disease activity was evaluated using the Systemic Lupus Erythematosus Activity Index 2000 (SLEDAI-2K). Renal severity was assessed by kidney biopsy. Results: Serum GlycA was elevated in active (n = 105) compared to quiescent SLE patients (n = 39, p &lt, 10&minus, 6), healthy controls (n = 20, p = 0.009) and KD controls (n = 21, p = 0.04), despite a more severely altered renal function in the latter. GlycA level was correlated to disease activity (SLEDAI-2K, &rho, = 0.37, p &lt, 4), Creactive protein, neutrophil count, triglyceride levels, proteinuria and inversely to serum albumin. In patients with biopsy-proven lupus nephritis (LN), GlycA levels were higher in proliferative (n = 26) than non-proliferative LN (n = 10) in univariate analysis (p = 0.04), and was shown to predict proliferative LN independently of renal parameters, immunological activity, neutrophil count and daily corticosteroid dosage by multivariate analysis (p &lt, 5 &times, 3 for all models). In LN patients with repeated longitudinal GlycA measurement (n = 11), GlycA varied over time and seemed to peak at the time of the flare. Conclusions: GlycA, as a summary measure for different inflammatory processes, could be a valuable biomarker of disease activity in patients with SLE, and a non-invasive biomarker of pathological severity in the context of LN.

Background Clinical heterogeneity, a hallmark of systemic autoimmune diseases (SADs) impedes early diagnosis and effective treatment, issues that may be addressed if patients could be grouped into a molecular defined stratification. Methods With the aim of reclassifying SADs independently of the clinical diagnoses, unsupervised clustering of integrated whole blood transcriptome and methylome cross-sectional data of 918 patients with 7 SADs and 263 healthy controls was undertaken. An inception cohort prospectively followed for 6 and 14 months was studied to validate the results in early cases and analyze if cluster assignment was modified with time. Results Four clusters were identified Three aberrant clusters were ‘acute phase inflammatory’, ‘T cell immunity’, and ‘interferon’, each including all diagnoses, were defined by genetic, clinical, serological and cellular features. A fourth cluster showed no specific molecular pattern, to which 74% of healthy controls clustered with patients. The inception cohort showed that most patients were either assigned always to the same cluster or moved from the healthy-like cluster to a single aberrant cluster resembling the relapsing-remitting dynamic of these diseases, showing that single aberrant molecular signatures characterize each individual patient. Conclusions Patients with SADs share molecular signatures and can be therefore stratified into three disease clusters differentiating each patient into a specific molecular disease pathway. Such assignment is stable with time. These results have important implications for understanding disease progression and therapy design marking a paradigm shift in our view of SADs. Acknowledgment This work has been supported through a grant from the Innovative Medicines Initiative Joint Undertaking No. 115565 and in-kind and in-cash contributions from the EFPIA partners. G.B. is supported by the Instituto de Salud Carlos III (ISCIII, Spanish Health Ministry), through the Sara Borrell subprogram (CD18/00153). The authors would like to particularly express their gratitude to the patients, nurses and many others who helped directly or indirectly in the consecution of this study.

ObjectivesChronic renal impairment remains a feared complication of lupus nephritis (LN). The present work aimed at identifying mechanisms and markers of disease severity in renal tissue samples from patients with LN.MethodsWe performed high-throughput transcriptomic studies (Illumina HumanHT-12 v4 Expression BeadChip) on archived kidney biopsies from 32 patients with LN and eight controls (pretransplant donors). Histological staging (glomerular and tubular scores) and immunohistochemistry experiments were performed on the same and on a replication set of 37 LN kidney biopsy samples.ResultsA group of LN samples was identified by unsupervised clustering studies based on their gene expression features, that is, the overexpression of transcripts involved in antigen presentation, T and B cell activation. These samples were characterised by a significantly lower estimated glomerular filtration rate (eGFR) at the time of biopsy (T0) compared with the other systemic lupus erythematosus samples. Yet, apparent disease duration at T0, double-stranded DNA antibody titres at T0 and other relevant characteristics (serum C3, proteinuria, histological scores, numbers of previous flares) were not different between groups.Immunohistochemistry studies confirmed the association between interstitial infiltration by adaptive immune effectors and decreased renal function in the same and in a replication group of LN kidney biopsies. This was associated with transcriptomic, histological and immunohistochemical evidence of renal tubular cell involvement.ConclusionInterstitial infiltration of LN kidney biopsies by adaptive immune effectors is associated with impaired renal tubular cell function and decreased eGFR. These results open new perspectives in evaluating and treating patients with LN, focusing on intrarenal mechanisms of immune cell activation.

Introduction De plus en plus de preuves indiquent que l’analyse du tissu synovial peut fournir des informations sur la physiopathologie, mais aussi des informations individuelles cliniquement pertinentes dans les arthrites inflammatoires a l’âge adulte. On sait peu de choses sur la pathologie synoviale dans l’arthrite juvenile idiopathique (AJI), notamment en ce qui concerne la variabilite des caracteristiques histopathologiques entre les patients. Evaluer l’heterogeneite des principales caracteristiques synoviales (hyperplasie des synoviocytes et infiltration des cellules immunitaires) chez les patients atteints d’AJI et les comparer a une cohorte de jeunes adultes ( Patients et methodes Les biopsies synoviales ont ete prelevees a l’aide d’une mini arthroscopie du genou ou d’une biopsie guidee par echographie lors d’une injection intra-articulaire dans l’articulation. Les tissus ont ete inclus dans de la paraffine puis les sections ont ete colorees a l’hematoxyline et a l’eosine. L’hyperplasie des synoviocytes (SH) et l’infiltration des cellules immunitaires (ICI) ont ete evaluees par un pathologiste experimente sur une echelle semi-quantitative de 0 a 3. Resultats 34 patients atteints d’AJI (âge (median±SD) : 15,5 ± 6,47 ans, AJI oligo-articulaire n = 28/34, AJI polyarticulaire n = 6/34, positivite ANA-RF-ACPA = 56 %-10 %-3 %) et 22 patients atteints de PR (âge (median ± SD) : 24,3 ± 2,6 ans, positivite ANA-RF-ACPA = 10 %–36 %–32 %) ont ete inclus. Les scores individuels de SH et ICI etaient correles a la fois dans l’AJI (r de Spearman = 0,503, valeur p = 0,0024) et la PR (r de Spearman = 0,636, valeur p = 0,0015). Il n’y avait pas de difference significative dans les scores SH et ICI entre les 2 groupes avec un score SH (Q25-Q50-Q75) dans l’AJI = 0,5-1,125-2 et dans la PR = 0,75-2-2) ; score ICI (Q25-Q50-Q75) dans l’AJI = 1-2-2 et dans la PR = 0,75–2–2,25). La variabilite intra-groupe des deux caracteristiques evaluees etait comparable entre les 2 groupes (coefficient de variation SH : 72,2 % pour l’AJI et 68,2 % pour la PR ; coefficient de variation ICI : 52,2 % pour l’AJI et 71,2 % pour la PR). Chez les patients atteints d’AJI, il n’y avait pas de difference significative dans les scores SH/ICI entre les groupes en fonction de la positivite des ANA, de l’atteinte oligo ou polyarticulaire ou du traitement en cours. Toutes les procedures ont ete bien tolerees. Conclusion En etudiant les principales caracteristiques histologiques de la synovite, nous n’avons trouve aucune difference entre les patients atteints d’AJI et les jeunes patients atteints de PR. En outre, nous rapportons un degre similaire d’heterogeneite inter-patients dans les caracteristiques pathologiques synoviales des patients atteints d’AJI et de PR. Ces variations ne s’expliquent pas par des caracteristiques cliniques communes. Pour savoir si elles sont liees a des signatures moleculaires differentes, comme cela a ete suggere dans la PR adulte, des investigations supplementaires sont prevues en utilisant le sequencage de l’ARN total de la synoviale

International audience; Biases in the distribution and phenotype of T, B, and antigen-presenting cell populations are strongly connected to mechanisms of disease development in mouse models of systemic lupus erythematosus (SLE). Here, we describe longitudinal changes in lymphoid and antigen-presenting cell subsets in bone marrow, blood and spleen from two lupus-prone strains (MRL/lpr and B6.Sle1.Sle2.Sle3 tri-congenic mice), and how they integrate in our present understanding of the pathogenesis of the disease. In particular, we focus on (autoreactive) T cell activation patterns in lupus-prone mice. Break of T cell tolerance to chromatin constituents (histone peptides) is key to the development of the disease and is related to T cell intrinsic defects, contributed by genetic susceptibility factors and by extrinsic amplificatory mechanisms, in particular over-stimulation by antigen-presenting cells. We also describe shifts in B cell sub-populations, going from skewed immature B cell populations as an indication of disturbed central and peripheral tolerance checkpoints, to enriched long-lived plasma cells, which are key to persistent autoantibody production in the disease. B cell activation mechanisms in SLE are both T cell-dependent (break of tolerance and production of specific autoantibodies) and -independent (polyclonal B cell activation, production of autoantibodies by long-lived plasma cells). By providing a comprehensive evaluation of B and T cell surface markers in two major mouse models of SLE and a description of their changes before and after disease onset, this review illustrates how the study of lymphoid cell phenotype delivers key information regarding pathogenic pathways and supplies tools to assess the beneficial effects of novel therapeutic interventions.

Objective The Euro-Lupus regimen of low-dose intravenous cyclophosphamide (IV CYC) (cumulative dose of 3 gm) was developed to reduce gonadal toxicity. To address the possibility of a marginal effect on the ovarian reserve, we measured serum titers of anti-Mullerian hormone (AMH) in patients with systemic lupus erythematosus (SLE) treated with the Euro-Lupus regimen and compared them with those measured in patients who were treated with higher doses of IV CYC or were never treated with IV CYC. Methods Serum AMH levels were measured by enzyme-linked immunosorbent assay in a cohort of 155 premenopausal SLE patients; 30 of these patients had been treated with the Euro-Lupus regimen, and 24 had received higher doses of IV CYC. None had received oral CYC. AMH levels were age-adjusted using a slope computed from levels measured across the group of SLE patients who had not been treated with IV CYC. Demographic and clinical data were collected. Results Serum titers of AMH measured in SLE patients treated with the Euro-Lupus IV CYC regimen (median dose 1.46 ng/ml) did not differ from those measured in patients never treated with the cytotoxic drug (median 1.85 ng/ml). As expected, patients given >6 gm of IV CYC had significantly lower serum titers of AMH (median 0.83 ng/ml) compared with those never treated with IV CYC (P = 0.047). Median serum AMH titers did not change before (1.24 ng/ml) and after (2.50 ng/ml) treatment with the Euro-Lupus IV CYC regimen in the subset of patients for whom paired samples could be tested (P = 0.43). Conclusion The Euro-Lupus regimen of low-dose IV CYC does not impact the ovarian reserve of SLE patients and can therefore be proposed as treatment in patients seeking to become pregnant.

Introduction La polyarthrite rhumatoide (PR) est une maladie heterogene dont la presentation clinique et les facteurs de pronostic sont differents, y compris le processus immunitaire au niveau de la synovie. Le developpement de la biopsie synoviale guidee par ultrasons permet de prelever du tissu synovial dans les petites articulations et facilite les etudes histopathologiques, ameliorant ainsi la comprehension de l’immunopathologie de la PR debutante. Les objectifs de cette cohorte sont de comparer les caracteristiques cliniques, biologiques et radiologiques de base et la reponse clinique au methotrexate (MTX) en fonction des caracteristiques inflammatoires du tissu synovial. Patients et methodes 152 patients souffrant de PR debutante repondant aux criteres ACR/EULAR 2010 et naifs au traitement par DMARD ont ete recrutes dans notre cohorte Bruxelles-UCLouvain. Les biopsies synoviales avant traitement ont ete obtenues par biopsie a l’aiguille guidee par ultrasons des petites articulations ou par mini-arthroscopie du genou. Les tissus preleves ont ete fixes, colores et paraffines pour une description en aveugle du pathotype tissulaire. Les pathotypes ont ete divises en 2 groupes selon l’absence ou la presence d’infiltrats inflammatoires (pauci-immun, score 0-1 vs inflammatoire, score 1-6) et l’absence ou la presence d’hyperplasie synoviale (score > 1). Les mesures de la maladie et de la reponse clinique ont ete evaluees tous les 3 mois dans le cadre du traitement au MTX. Resultats L’âge moyen de la population est de 48,3 ans. 63,2 % des patients sont des femmes. 24,6 % sont des fumeurs et 62,3 % ont des anticorps anti-peptides citrullines (ACPA). Les caracteristiques histologiques sont resumees dans le tableau. La presence d’ACPA est plus eleve dans le groupe pauci-immun et significativement superieure dans le groupe sans hyperplasie synoviale. Les niveaux de CRP sont significativement plus eleves chez les patients presentant le pathotype inflammatoire et de l’hyperplasie synoviale. La reponse clinique (DAS-44, SJC et CRP) etait statistiquement meilleure apres 3 mois de traitement par le MTX chez les patients presentant un pathotype inflammatoire et de l’hyperplasie, avec un taux de CRP plus bas observe a 6 et 12 mois par rapport au groupe pauci-immun. Conclusion L’analyse du tissu synovial nous permet de mieux definir le spectre clinique et immunologique de la PR debutante. Nous avons demontre une predominance de patients ACPA+ dans le groupe pauci-immun. Une meilleure reponse clinique au MTX a ete observee chez les patients presentant des infiltrats inflammatoires ou une hyperplasie synoviale. D’autres etudes sont en cours pour valider ces facteurs pronostiques pour optimaliser le traitement de la PR debutante.

SUMMARYBackgroundClinical heterogeneity, a hallmark of systemic autoimmune diseases (SADs) impedes early diagnosis and effective treatment, issues that may be addressed if patients could be grouped into a molecular defined stratification.MethodsWith the aim of reclassifying SADs independently of the clinical diagnoses, unsupervised clustering of integrated whole blood transcriptome and methylome cross-sectional data of 918 patients with 7 SADs and 263 healthy controls was undertaken. In addition, an inception cohort was prospectively followed for 6 and 14 months to validate the results and analyze if cluster assignment changed or not with time.ResultsFour clusters were identified. Three clusters were aberrant, representing ‘inflammatory’, ‘lymphoid’, and ‘interferon’ patterns each including all diagnoses and defined by genetic, clinical, serological and cellular features. A fourth cluster showed no specific molecular pattern and accumulated also healthy controls. An independent inception cohort showed that with time, the molecular clusters remain stable, showing that single aberrant molecular signatures characterize each individual patient.ConclusionsPatients with SADs can be jointly stratified into three stable disease clusters with specific molecular patterns differentiating different molecular disease mechanisms. These results have important implications for future clinical trials and the study of therapy non-responsiveness marking a paradigm shift in the view of SADs.

BackgroundSystemic lupus erythematosus (SLE) is a clinically heterogeneous autoimmune disease characterized by the development of anti-nuclear antibodies. Susceptibility to SLE is multifactorial, with a combination of genetic and environmental risk factors contributing to disease development. Like other polygenic diseases, a significant proportion of estimated SLE heritability is not accounted for by common disease alleles analyzed by SNP array-based GWASs. Death-associated protein 1 (DAP1) was implicated as a candidate gene in a previous familial linkage study of SLE and rheumatoid arthritis, but the association has not been explored further.ResultsWe perform deep sequencing across the DAP1 genomic segment in 2032 SLE patients, and healthy controls, and discover a low-frequency functional haplotype strongly associated with SLE risk in multiple ethnicities. We find multiple cis-eQTLs embedded in a risk haplotype that progressively downregulates DAP1 transcription in immune cells. Decreased DAP1 transcription results in reduced DAP1 protein in peripheral blood mononuclear cells, monocytes, and lymphoblastoid cell lines, leading to enhanced autophagic flux in immune cells expressing the DAP1 risk haplotype. Patients with DAP1 risk allele exhibit significantly higher autoantibody titers and altered expression of the immune system, autophagy, and apoptosis pathway transcripts, indicating that the DAP1 risk allele mediates enhanced autophagy, leading to the survival of autoreactive lymphocytes and increased autoantibody.ConclusionsWe demonstrate how targeted sequencing captures low-frequency functional risk alleles that are missed by SNP array-based studies. SLE patients with the DAP1 genotype have distinct autoantibody and transcription profiles, supporting the dissection of SLE heterogeneity by genetic analysis.

ObjectivesWe explored histological and transcriptomic profiles of paired synovial biopsies from rheumatoid arthritis (RA) patients, in order to assess homogeneity in synovial tissue at the individual level.MethodsSynovial biopsies were performed simultaneously in one small and one large joint per patient using needle-arthroscopy for the knee and ultrasound-guided biopsy for the hand or wrist. Synovium from individuals with osteoarthritis was used as controls. Paraffin-embedded samples were stained for CD3, CD20, and CD68. Total RNA was hybridized on high-density microarrays. TCRB variable sequences were obtained from synovial and blood RNA samples.ResultsTwenty paired biopsies from 10 RA patients with active disease were analyzed. Semi-quantification of histological markers showed a positive correlation for synovial hyperplasia, inflammatory infiltrates and CD3-positive T cells between pairs. Pairwise comparison of transcriptomic profiles showed similar expression of RA-related molecular pathways (TCR signaling, T cell costimulation and response to TNFα). T cells clonotypes were enriched in all but one joints compared to blood, regardless of the magnitude of T cell infiltration. Enriched clonotypes were shared between pairs (23–100%), but this was less the case in pairs of joints displaying weaker T cell signatures and more pronounced germinal center-like transcriptomic profiles.ConclusionCellular and molecular alterations in RA synovitis are similar between small and large joints from the same patient. Interindividual differences in magnitude of T cell infiltrates and distribution of enriched T cell clonotypes support the concept of distinct synovial pathotypes in RA that are associated with systemic versus local antigen-driven activation of T cells.

Objective Type I IFNs play a well-known role in the pathogenesis of SLE, through activation of CD4 T and antigen-presenting cells. Here, we investigated the effects of IFN alpha (IFNα) on SLE B cell activation and differentiation. Methods Peripheral blood mononuclear cells (PBMCs) and purified total or naïve B cells were obtained from healthy controls and SLE patients. The effects of IFNα on B cell differentiation were studied by flow cytometry. The role of STAT3 in B cell responses to IFNα was studied using pharmacological inhibitors and PBMCs from STAT3-deficient individuals. Results Incubation of normal PBMCs with IFNα induces a B cell differentiation pattern as observed spontaneously in SLE PBMCs. IFNα displays direct stimulatory effects on purified naïve B cells from healthy individuals, as evidenced by a significant induction of cell surface CD38 and CD95 in the presence of the cytokine. In purified naïve B cells, IFNα also induces STAT3 phosphorylation. IFNα-induced naïve B cell differentiation in total PBMCs is significantly inhibited in the presence of STAT3 inhibitors, or in PBMCs from individuals with STAT3 loss of function mutations. Spontaneous levels of STAT3, but not STAT1, phosphorylation are significantly higher in total B cells from SLE patients compared with controls. Pharmacological STAT3 inhibition in SLE PBMCs inhibits naïve B cell activation and differentiation. Conclusion IFNα displays direct stimulatory effects on B cell differentiation and activation in SLE. STAT3 phosphorylation mediates the effects of IFNα stimulation in naïve B cells, an observation that opens new therapeutic perspectives in SLE.

Background Pathogenesis and aetiology of systemic sclerosis (SSc) are currently unclear, thus rendering disease prognosis, diagnosis and treatment challenging. The aim of this study was to use paired skin biopsy samples from affected and unaffected areas of the same patient, in order to compare the proteomes and identify biomarkers and pathways which are associated with SSc pathogenesis. Methods Biopsies were obtained from affected and unaffected skin areas of SSc patients. Samples were cryo-pulverised and proteins were extracted and analysed using mass spectrometry (MS) discovery analysis. Differentially expressed proteins were revealed after analysis with the Progenesis QIp software. Pathway analysis was performed using the Enrichr Web server. Using specific criteria, fifteen proteins were selected for further validation with targeted-MS analysis. Results Proteomic analysis led to the identification and quantification of approximately 2000 non-redundant proteins. Statistical analysis showed that 169 of these proteins were significantly differentially expressed in affected versus unaffected tissues. Pathway analyses showed that these proteins are involved in multiple pathways that are associated with autoimmune diseases (AIDs) and fibrosis. Fifteen of these proteins were further investigated using targeted-MS approaches, and five of them were confirmed to be significantly differentially expressed in SSc affected versus unaffected skin biopsies. Conclusion Using MS-based proteomics analysis of human skin biopsies from patients with SSc, we identified a number of proteins and pathways that might be involved in SSc progression and pathogenesis. Fifteen of these proteins were further validated, and results suggest that five of them may serve as potential biomarkers for SSc.

Background The Tool for Administrative Reimbursement Drug Information Sharing (TARDIS) is an electronic platform combining data collection from patients with Rheumatoid Arthritis (RA) on biologic and synthetic targeted therapy, together with the submission of a request for reimbursement of this medication. Objectives To present the first data ever of the TARDIS-RA registry concerning the use of biologic and synthetic targeted therapy across Belgium. Methods The Belgian TARDIS-RA registry started in April 2015. All Belgian rheumatologist were obliged after a transition period to insert patient data via the online portal when prescribing. If data of a patient are entered for the first time, previous and current use of classical synthetic (cs), targeted synthetic (ts) and biologic (b) disease modifying antirheumatic drug (DMARD) therapies is registered. Afterwards, every next bDMARD or tsDMARD initiation, prolongation and discontinuation is registered electronically in the system. Other data captured are basic demographic information such as age, gender and disease duration and disease characteristics including ESR, CRP, joint counts, disease activity scores and HAQ. Results At 18/01/2019, information on 80 098 drug prescriptions in 13 614 patients was collected in the TARDIS-RA registry. Of these 80 098 drug prescriptions, 30 434 (38.0%) were csDMARDs and glucocorticoids, and 49 664 (62.0%) were bDMARD or tsDMARD prescriptions. This last category consisted of 30 380 (61.2%) tumour necrosis factor inhibitor (TNFi) bDMARDs, 17 104 (34.5%) non-TNFi bDMARDs and 2 170 (4.3%) tsDMARDs. Only 642 (2.3%) TNFi biosimilar prescriptions were registered. Fig1 shows the yearly evolution of bDMARD and tsDMARD prescription in Belgium from 2015 to 2018. At first registered interaction with the rheumatologist, the 13 614 patients had a median (IQR) age of 59 (50-68) years with a median (IQR) disease duration of 9 (4-16) years; 9 666 (73.4%) were female. The clinical characteristics showed a median (IQR) DAS28CRP of 3.6 (2.1-4.8) and a median (IQR) HAQ of 1.1 (0.6-1.8). Of patients at first time registration, 37.6% could be validated as being bionaive and 62.5% as bioexperienced. Conclusion Approximately 70 000 individuals in Belgium are estimated to have a RA diagnosis. Corresponding to numbers of other western European countries, 20%-25% of them would be expected to receive ts/bDMARDs. This suggests that almost the entire Belgian RA population on biologic treatment is covered by TARDIS. The registration of initiation, prolongation and discontinuation of every ts/bDMARD since 2015 combined with the simultaneous collection of demographic and clinical data, will make the TARDIS-RA registry a useful and powerful tool for the long-term drug analyses in Belgian patients with RA. Disclosure of Interests Diederik De Cock: None declared, Patrick Durez Speakers bureau: Bristol-Myers Squibb, Eli Lilly, Sanofi, Celltrion, Dirk Elewaut: None declared, Bernard Lauwerys: None declared, Rene Westhovens Grant/research support from: Bristol-Myers Squibb, Consultant for: Celltrion, Galapagos-Gilead, Patrick Verschueren Grant/research support from: Unrestricted Pfizer Grant for Early RA research

Background Rheumatoid Arthritis (RA) is a chronic and heterogenous condition characterized by inflammatory involvement of the synovial membrane in multiple joints. Synovial biopsies are used in research setting in order to identify diagnostic and theranostic markers. Many studies have shown a high degree of heterogeneity in histological and transcriptomic profiles between patients. Objectives We wanted to explore histological and transcriptomic profile of synovial biopsies across pairs of joints in the same patients to assess heterogeneity at the individual level. Methods Synovial biopsies were performed simultaneously in one small and one large joint per patient using needle-arthroscopy for the knee and US-guided needle biopsy for the hand or foot. Synovium from individuals with osteoarthritis (OA) were used as control. Paraffine-embedded samples were stained for CD3, CD 20, CD 68 and CD138. Whole-tissue RNA was extracted and hybridized on GeneChip Human Genome U133 Plus 2.0 Array (Affymetrix). The samples were tested for RNA integrity by Bioanalyzer (Agilent). Normalization and statistical analyzes were performed on Genespring. Pathway analysis were performed using DAVID. Results 10 RA patients were included (females: 10/10, ACPA/RF positivity: 8/10, mean age (± SEM): 54.4 (± 4.4) years, mean disease duration (± SEM): 13.3 (± 3.7) years, mean DAS28CRP (± SEM): 5.01 (± 0,34), mean HAQ (± SEM): 1.7 (± 0.28)). Quantification of histological markers did not show differences in population of macrophages, plasmocytes, T and B Cells, across pairs of joints. After correction for multiple comparisons, no transcripts were differentially expressed between large and small joints. Similarly, we did not find any significant difference in the expression of transcripts involved in pathways (TCR-activation and cell-division) specifically overexpressed in RA compared to OA synovial tissue. In order to increase our ability to observe pair-wise differences in gene expression profiles, we studied correlations between transcripts significantly overexpressed in RA compared to OA joints with a fold change > 2 (n = 581) and clinical or biological markers of disease activity (DAS28-CRP, CRP, Physician Global Assessment of disease activity). Similar patterns of correlations indicated that disease activity was not driven by different pathways in small versus large joints. Conclusion This study is an important methodological milestone in the field of synovial biopsies, as it indicates that cellular and molecular alterations occurring in RA synovitis are similar across small and large joints from the same patient. Hence, biopsy of a single joint is representative and can be used to explore pathogenic processes or potential biomarkers in RA. Acknowledgement This work was funded in part by grants from Cap48 (RTBF), Fonds National de la Recherche Scientifique (FNRS, Communaute francaise de Belgique) and Fondation Saint-Luc. Disclosure of Interests Clement Triaille: None declared, Louise Vansteenkiste: None declared, Laurent Meric de Bellefon: None declared, Adrien Nzeusseu: None declared, Christine Galant: None declared, Patrick Durez Speakers bureau: Bristol-Myers Squibb, Eli Lilly, Sanofi, Celltrion, Bernard Lauwerys: None declared

Background: Several studies have demonstrated that Rheumatoid Arthritis (RA) patients achieving low disease activity or remission are able to taper biological disease-modifying antirheumatic drugs (bDMARDs). Objectives: The aim of this study is to evaluate the proportion of patients in whom the bDMARD can be tapered in daily practice and to analyse the characteristics of these patients e. Another objective is to determine which bDMARDs are more adapted to dose reduction and the cost saving. Methods: Inclusion criteria were RA patients from our Brussels UCL cohort treated with a bDMARD for at least one year. A dose reduction was proposed by the senior physician when sustained low disease activity or remission was achieved. Patient characteristics and baseline features before the introduction of the current bDMARD were collected as well as flares if happened. We also calculated, for each bDMARD, the proportion of patients who received a decreased dose and the annual cost. Results: Data from 332 eligible RA patients were collected, 140 patients (42,1%) had a tapered regimen and 192 received a full dose of bDMARD. In the decreased dose group, age at diagnosis (43.1 vs 38.7 years, p=0.004), HAQ (1.3 vs 1.5, p=0.048), RF (83.3 vs 72.9%, p=0.026) and disease duration at the bDMARDs introduction (9.7 vs 12.1 years, p=0.034) were statistically different. As expected, the current DAS28-CRP was lower (2.26 vs 2.64, p=0.001) in the decreased dose group and interestingly, more patients receiving a decreased dose were treated with a combination of methotrexate when the bDMARD was introduced (86.7% vs 73.8%, p=0.005). No difference between groups was observed for gender, ACPA, erosion, number of previous bDMARDs, time to first conventional synthetic DMARD and biological DMARD, baseline DAS28-CRP and use of glucocorticoids. In our cohort, anti-TNF agents were the most commonly prescribed medications (anti-TNF 68%, tocilizumab 15%, rituximab 10%, abatacept 7%). Only 15 patients experienced a flare during the follow-up. Adalimumab, etanercept and rituximab were the most frequent decreased bDMARD and were associated with the most important reduction of annual cost. ABA : abatacept, ADA : adalimumab, CZP : certolizumab, ETN : etanercept, GOL : golimumab, IFX : infliximab, RTX : rituximab, TOC : tocilizumab Conclusion: In daily practice, tapering of bDMARDs in RA patients with low disease activity or remission is an achievable goal in a large proportion of patients, thereby reducing annual drug cost. The combination with methotrexate could be a positive predictive factor for the success of bDMARD tapering but further prospective research in daily practice are needed to confirm this result. Disclosure of Interests: Stephanie Dierckx: None declared, Bernard Lauwerys: None declared, Tatiana Sokolova: None declared, Laurent Meric de Bellefon: None declared, Maria Stoenoiu Grant/research support from: Abbvie, Roche, Wyeth, Adrien Nzeusseu: None declared, Frederic Houssiau: None declared, Aleksandra Avramovska: None declared, Patrick Durez Speakers bureau: Bristol-Myers Squibb, Eli Lilly, Sanofi, Celltrion

Background: Pathogenic antibody secreting cells (ASC) have been identified in the kidney of SLE-prone mice, but are poorly characterized in human lupus nephritis (LN). We hypothesized that long-lived plasma cells may contribute to the failure of immunosuppressive therapy in refractory patients. Objectives: To characterize and compare the single cell molecular signature of ASC in kidney and urine from patients with active LN, either untreated or after immunosuppressive therapy failure. Methods: We included patients with biopsy proven active LN from 4 centers and meeting the ACR revised classification criteria for SLE diagnosis. Renal biopsies were scored according to 2003 International Society of Nephrology/Renal Pathology Society (ISN/RPS) classification, and stained with anti-CD138 to visualize ASC. ASC were single cell sorted as CD3-/CD14-/CD16-/CD27high/CD38high cells. Single-cell gene expression profiling was performed by multiplex RT-PCR using Fluidigm Dynamic Arrays. We used a set of genes derived from a previous transcriptomic analysis of human splenic and bone marrow ASC to distinguish the process of ASC maturation from plasmablast (PB) to long-lived PC. We also studied ASC transcriptional program from urine of untreated LN patients at diagnosis and after 3 and 6 months of a prospective follow up during induction therapy (Plasmo-Lup study). Results: Immunohistochemistry stainings on kidney biopsies from both untreated (N=15) and refractory patients (N=6) showed infiltrates of CD138+ ASC mainly located in the interstitium, particularly in untreated patients. Single cell molecular signature of kidney ASC from 3 untreated patients with class IV LN revealed that these cells were mostly PB expressing multiple genes linked with cell division, and PC without long-lived genes expression. This contrasted with ASC signature from 3 patients with active LN and mycophenolate mofetil (MMF) failure that expressed long-lived PC genes and no proliferative genes. Primary component analysis of 170 single-cells showed clustering of ASC from MMF treated patients with long-lived bone marrow PC from healthy donors that were distinct from PB/PC from untreated patients (Figure 1). A PB signature was observed in urine ASC at diagnosis, similar to their kidney counterpart. The concentration of ASC in urine in 22 untreated patients correlated with ISN/RPS classification, with higher concentration in class IV patients (p Conclusion: These results suggest that PB infiltrate kidney of untreated LN patients, and that kidney long-lived PC may contribute to the failure of immunosuppressive therapy. Acknowledgement: This work was supported by Foreum Disclosure of Interests: None declared

Background: Factors contributing to poor renal outcomes in lupus nephritis (LN) are poorly understood. In our previous research, we found an association between the presence of activated immune effectors in the lupus kidney and disease severity. Here we investigated correlations between patterns of renal genes expression and biological parameters of renal disease activity in a mouse model of systemic lupus erythematosus (SLE). Methods: We collected blood, urine, kidneys and spleens from 33 B6/Sle1.Sle2.Sle3 congenic mice, before disease onset at 3 months (n=8), and at different stages of disease progression, at 6 (n=7), 9-10 (n=12) and 17-18 (n=5) months. RNA was extracted from kidneys, and hybridized on Mouse Gene 2.0 ST exon arrays. Unsupervized hierarchical clustering studies and pathways analyses were performed on Genespring and DAVID softwares. Spleen and kidney CD8 T cell activation and differentiation markers were evaluated by flow cytometry (CD8, CD69, CD62L, CD44, CD122, CD25, CD44, CCR7, CD279, CD152, CD11a, CD103). Plasma urea and albuminuria were measured by immunoassay. Results: 712 (out of 33,793) transcripts were overexpressed in kidneys from diseased mice (age > 6 months). These transcripts were significantly enriched in the following pathways: response to type I interferons, antigen processing and presentation, activation and regulation of B cells, complement activation, and regulation of cytotoxicity mediated by T cells. Proportions of renal CD8 T cells with an effector phenotype were significantly increased in the kidneys from 6 months and older compared to younger mice, and compared to paired spleens. Proportions of renal effector CD8 T cells correlated significantly with transcripts involved in interferon signature, adaptive immune responses, cytotoxic T cells, chemotaxis, and correlated negatively with pathways associated with renal tubular cell functions. Finally, we found a correlation between biological parameters of kidney function (plasma urea, albuminuria) and transcripts involved in pro-fibrotic pathways, chemokines and adaptive immune responses. Conclusion: Our results confirm the link between the presence of activated immune effectors in the kidney and renal outcomes in a mouse model of SLE, similar to our previous observations in human LN, and warrant further functional studies on the role of kidney-infiltrating T and B cells in this model. Acknowledgement: This research was funded in part by grants from Fonds de la Recherche Scientifique – FNRS, Fondation Roi Baudouin and Fondation Saint-Luc. Disclosure of Interests: None declared