tbuckley/cabot-search huggingface dataset:
POS0025 ACTIVATION OF NOTCH1 SIGNALING IN FIBROBLASTS IS SUFFICIENT TO INDUCE FIBROSIS AND ACTIVATES A NETWORK OF PROFIBROTIC SIGNALING CASCADES
Authors: C. Dees, A. Kalyva, C. Bergmann, M. Kunz, G. Schett, J. Distler
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background:</h3> Fibrosis is caused by an excessive accumulation of extracellular matrix proteins released from persistently activated fibroblasts and is a major hallmark of systemic sclerosis (SSc). Notch signaling plays a key role in development of many tissues and cell types, and aberrant Notch signaling has been shown to contribute to fibroblast activation and tissue fibrosis in the past. However, the precise role of Notch signaling in the molecular network of fibrotic pathways remains unknown. <h3>Objectives:</h3> The aims of the present study were to evaluate whether constitutive activation of Notch signaling in fibroblasts is sufficient to induce fibrosis, and to identify the regulatory effects of Notch signaling on other profibrotic pathways. <h3>Methods:</h3> Mice with alleles for the active Notch1<sup>ICD</sup> inserted into the <i>GT(ROSA)26Sor</i> locus were crossbred with tamoxifen-inducible Col1a2-CreER mice to yield mice expressing both <i>GT(ROSA)26Sor</i><sup><i>Notch1ICD</i></sup> and Col1a2-CreER (Notch1<sup>ICD</sup>;Col1a2-CreER). Fibrosis outcomes were analysed 4, 12, and 20 weeks after Cre induction with tamoxifen. Expression profiles and cellular processes were analysed by RNAseq and bioinformatical modeling. Identified differentially expressed genes were confirmed by qPCR and immunofluorescence co-staining. <h3>Results:</h3> Fibroblast-specific activation of Notch signaling induced dermal fibrosis in a time-dependent manner with median increases in dermal thickness by 72 %, of the hydroxyproline content by 77 %, and the myofibroblast counts by 148 %. The expression of the classical Notch target genes Hes1 and Hey1 increased by 2.1- and 3.8-fold, respectively. In addition to dermal fibrosis, mice with conditional activation of Notch1 signaling also displayed fibrotic changes in the lungs and the colon. RNA sequencing analysis of the skin showed an upregulation of pro-fibrotic genes such as different types of collagens, MAP kinases, and components of JAK-STAT signaling amongst others. On the contrary, induction of Notch signaling in fibroblasts decreased the expression of anti-fibrotic genes such as the Wnt pathway inhibitors Wif1 and Sfrp1, the inhibitory Smad7, and vitamin D receptor Vdr. <h3>Conclusion:</h3> We demonstrate that activation of Notch signaling in fibroblasts is sufficient to induce fibrosis <i>in vivo</i>. Cross-activation of different pro-fibrotic pathways with parallel repression of anti-fibrotic mediators might contribute to Notch1-induced fibrogenesis. Fibroblast-specific activation of Notch signaling might be an additional experimental model for testing anti-fibrotic molecules. <h3>REFERENCES:</h3> <b>NIL.</b> <h3>Acknowledgements:</h3> <b>NIL.</b> <h3>Disclosure of Interests:</h3> <b>None declared.</b>
POS0039 HIGH THROUGHPUT MULTIPLEX ASSAY IDENTIFIES CLINICALLY MEANINGFUL CLUSTERS IN SYSTEMIC SCLEROSIS PATIENTS WITH LOW CARDIOVASCULAR RISK AND NO HISTORY OF HEART DISEASE.
Authors: R. R. Shukla, R. B. Dumitru, B. Erhayiem, G. Fent, F. Del Galdo, S. Plein, D. Plant, M. Buch
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background:</h3> People with systemic sclerosis (SSc) often show subclinical evidence of primary heart involvement (pHI)[1], which when clinically evident, is a prognostic factor of poor outcome. <h3>Objectives:</h3> We aimed to profile serum proteins in patients with SSc and no history of pHI and identify clinically meaningful clusters to aid early identification and stratification for pHI. <h3>Methods:</h3> Serum from 78 patients from CONVAS ('CONnective Tissue Disease and VASculitis Cohort') and ELCASA ('ELectrophysiology and CArdiac imaging in SclerodermA') cohorts with no history of pHI, pulmonary hypertension, diabetes or &gt;2 traditional cardiovascular (CV) risk factors was used to measure 355 protein levels across inflammation, cardiometabolic and cardiovascular II/III Olink panels. Unsupervised hierarchical clustering using scaled normalised protein expression was used to define clusters. Demographic and clinical characteristics were compared between clusters and significant differences reported using Kruskal-Wallis rank sum test for continuous or Pearson's chi-squared test for categorical variables, at the 5% significance threshold. <h3>Results:</h3> Clinical characteristics of the patient cohorts have been previously published and are summarised in Figure 1A (column 2). Unsupervised hierarchical clustering revealed 3 patient clusters – C1 [27/78 (35%)], C2 [33/78 (42%)] and C3 [18/78 (23%)] with intermediate, low and high protein expression respectively (Figure 1B). Top 5 proteins contributing to the clustering were IL18BP, TNFR1, TNFR2, TNFRSF14, and PAR1. C2 patients were younger (median age 51 years) compared to C1 (61 years) and C3 (58 years) (p &lt;0.001). High expression cluster C3 had a significantly higher proportion of males [7/18 (39%)](p = 0.009), shorter disease duration [median 1.15 years, IQR (0.66 to 7.23)], higher modified Rodnan skin scores (MRSS) [median 5.50, IQR (3.25 to 11)] (p = 0.002) and current disease modifying anti-rheumatic drugs (DMARD) use [16/18 (89%)](p = 0.005). NTproBNP and CRP were elevated in C1 and C3, and high-sensitivity troponin I (hsTnI) was highest in C3[median 6.15 IQR (5.08 to 89.58)](p = 0.002); although n=3 within C1 (black box Figure 1A) showed especially high NTproBNP (median 227.50pg/ml) and C-reactive protein (median 13mg/dl). No differences in antibody profiles were noted across the three clusters (Figure 1A). <h3>Conclusion:</h3> Differences in serum protein expression identifies clinically meaningful clusters of SSc patients with elevated acute phase and serum cardiac markers despite low CV risk profile. Future work should assess their utility as prognostic biomarkers of SSc-pHI. <h3>REFERENCES:</h3> [1] Dumitru RB et. al., RMD Open. 2021 Oct;7(3):e001689. <h3>Acknowledgements:</h3> <b>NIL.</b> <h3>Disclosure of Interests:</h3> <b>None declared.</b>
POS0476 LUNG INVOLVEMENT IN EARLY RHEUMATOID ARTHRITIS, ANALYSIS OF ERA UCLOUVAIN BRUSSELS FINDRA COHORT
Authors: P. Durez, A. Froidure, M. Doyen, M. Perrot, B. Ghaye, E. Sapart, B. Bearzatto, J. F. Durant, J. Ambroise, J. L. Gala, D. Zan, A. Avramovska, T. Sokolova, S. Koenig
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background:</h3> The prevalence of lung involvement in rheumatoid arthritis (RA) remains elusive. <h3>Objectives:</h3> We set up a prospective study to detect ILD, bronchiolitis and nodules in early RA. <h3>Methods:</h3> The Factors of ILD in Newly Diagnosed RA (FINDRA, NCT04002765) study is a prospective multicentric trial. We proposed inclusion to patients with a newly diagnosed RA according to ACR/EULAR criteria and defined early disease as symptoms present for at least 1 year and maximum 10 years. After informed consent, patients underwent full respiratory evaluation consisting of an environmental questionnaire, HRCT, pulmonary function tests (PFT) and sampling for genetic analysis of common variants associated with RA-ILD. HRCT were centrally reviewed for the presence of ILD (primary outcome), expiratory trapping and nodules (secondary outcomes). <h3>Results:</h3> We screened290 patients and excluded 32 who did not undergo the requested exams (N=30) or had a RA diagnosis older than 10 years (N=2). The median age of the 258 included patients was 56 years-old. The majority (71%) were female, 48% were ex- or current smokers. 71% had a positive rheumatoid factor and 67% positive anti-citrullinated peptides antibodies. The majority ware treated with methotrexate (77%) and/or another DMARD (50%). We detected ILD in 38 patients (15%), emphysema in 51 (20%) and bronchiolitis in 89 (41%). Older age, male sex, disease activity and low diffusion capacity (DLCO) were associated with ILD; older age, male sex, smoking status and low DLCO were associated with emphysema. Finally, neither of the variables associated with air trapping. <h3>Conclusion:</h3> In this multicentric prospective study with HRCT central review, lung involvement affected a high proportion of RA patients, bronchiolitis being the most prevalent, followed by emphysema and ILD. Old age and male sex were associated with both ILD and emphysema, suggesting that we should prioritize screening in this population. Analysis with genetic testings are ongoing. <h3>REFERENCES:</h3> <b>NIL.</b> <h3>Acknowledgements:</h3> <b>NIL.</b> <h3>Disclosure of Interests:</h3> <b>None declared.</b>
OP0171 SINGLE-CELL IMMUNE LANDSCAPE OF AFFECTED LUNGS FROM THE PATIENTS WITH ANTI-MDA5-POSITIVE DERMATOMYOSITIS
Authors: Z. Chen, S. Ye, Q. Fu, X. Zhang
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background:</h3> Anti-melanoma differentiation-associated gene 5-positive dermatomyositis (MDA5+ DM) a distinct subtype of dermatomyositis associated with rapidly progressive interstitial lung disease and high mortality. The aetiology and pathogenesis of MDA5+ DM are largely unknown which pose great difficulty to develop novel therapeutic options. <h3>Objectives:</h3> To explore the immune landscape and identify disease-specific immune cells of the affected lungs from the MDA5+ DM patients who underwent lung transplantation. <h3>Methods:</h3> Six lung tissues from end-stage MDA5+ DM patients were obtained and processed into single-cell suspensions. Cells were subjected to scRNA-seq, scBCR-seq and scTCR-seq using the 10x Genomics Chromium platform. For comparisons, twelve lung tissues from healthy individuals, eleven from the patients with idiopathic pulmonary fibrosis (IPF) and seven Covid19 patients were collected from public datasets (GSE136831, GSE159585). <h3>Results:</h3> Compared with health individual and other lung diseases, we observed a decrease of alveolar epithelial cells with high infiltration of macrophages in the lungs of MDA5+ DM patients. A panel of pathways, including type I and II interferon responses, inflammatory response, apoptosis and reactive-oxygen-species-pathway were strongly elevated in the macrophages from MDA5+ DM patients. Furthermore, the proportion of CXCL10+ macrophage cluster was significantly increased and intensely interacted with T cells. scBCR-seq and scTCR-seq analyses revealed that B cells and T cells exhibited strong clonal expansions in the affected lungs of MDA5+ DM patients, indicating intensive cellular and humoral responses occurred <i>in situ</i>. We validated the abnormal activation of macrophages, T cells and B cells by mIHC. Finally, we found a potential link between overactivation of CXCL10+ macrophages and fibrosis. <h3>Conclusion:</h3> The innate and adaptive immune systems were highly activated and dysregulated in the lungs of active MDA5+ DM patients. Targeting disease-specific immune cell types may provide new therapeutic opportunities for MDA5+ DM. <h3>REFERENCES:</h3> <b>NIL.</b> <h3>Acknowledgements:</h3> This study was supported by the National Key Research and Development Program of China (No. 2021YFE0200600). <h3>Disclosure of Interests:</h3> <b>None declared.</b>
POS1000 EXPRESSION OF GLYCOSYLATED DSRNA ON THE SURFACE OF MONOCYTES IN PATIENTS WITH SJOGREN SYNDROME
Authors: E. Balbinot, G. Buoncuore, C. Barbati, M. Caliste, V. Manganelli, M. Sorice, R. Priori, C. Alessandri, F. Conti
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background:</h3> Recent studies have demonstrated that different types of cells express surface glycosylated RNA (glicoRNA). Through this mechanism, they are exposed to the extracellular space and, consequently, to the immune system. In particular, a glycosylated surface ds-RNA (glico-dsRNA) has been identified using the anti-dsRNA J2 antibody. <h3>Objectives:</h3> The purpose of this study was to evaluate the monocytic expression of the glico-dsRNA and correlate it with the clinical and laboratory characteristics of patients with Sjogren Syndrome (SjS). <h3>Methods:</h3> Ten patients diagnosed with SSj and ten healthy control donors (HD) matched for sex and age were evaluated. Demographic and clinical data were collected from these patients, and venous blood was drawn. Mononuclear cells from peripheral blood (PBMC) were isolated from the blood. RNase A was added to the sample and incubated. After washing, the cells were incubated with anti-dsRNA J2 antibody. Subsequently, the cells were incubated with Goat anti-Mouse-IR 680 antibody. Finally, acquisition was performed using a FACS Calibur flow cytometer and 20,000 events per sample were evaluated. The data were analyzed using Cell Quest Pro software. Titers of anti-Ro60 and Ro52 antibodies were measured using ELISA. <h3>Results:</h3> The clinical and laboratory characteristics of the patients are summarized in Table 1. Our study revealed that patients with SSj express a higher percentage of glyco-dsRNA on the surface of monocytes (median=38; σ=27.2) compared to HD (median=11; σ=6.1) (p= 0.001) (Figure 1 and 3), and that monocytic expression of glyco-dsRNA correlates with disease activity assessed by ESSDAI (p=0.0001) (Figure 2). Finally, we demonstrated that the expression of glyco-dsRNA on monocytes does not correlate with the antibody titers of antiRo60 (p-value=0.3) and antiRo52 (p-value=0.8). <h3>Conclusion:</h3> The results demonstrate that the expression of glyco-dsRNA on the cell surface of monocytes is increased in patients with SSj compared to HD and that this expression correlates with disease activity. Therefore, glyco-dsRNA could potentially represent a new surface antigen involved in the pathogenesis of these diseases and serve as a new marker of disease activity. <h3>REFERENCES:</h3> [1] Small RNAs are modified with N-glycans and displayed on the surface of living cells. Flynn R. et al. Cell 2021 Jun 10;184(12):3109-3124.e22. <h3>Acknowledgements:</h3> <b>NIL.</b> <h3>Disclosure of Interests:</h3> <b>None declared.</b>
POS0274 PLASMA EXTRACELLULAR VESICLES PROMOTE FOLLICULAR T HELPER CELL EXPANSION IN PRIMARY SJÖGREN’S SYNDROME
Authors: S. Liu, C. Luo, C. He, J. Sun, Z. Chen, T. Lyu, F. Zhang, H. Chen
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background:</h3> Plasma extracellular vesicles (EVs) are elevated in primary Sjögren's syndrome (pSS) patients, whose function remains unclear. <h3>Objectives:</h3> To explore the potential function of plasma EVs on T cell dysregulation in pSS. <h3>Methods:</h3> Plasma EVs from pSS patients or healthy controls (HCs) were isolated, characterized, and quantified using transmission electron microscope, nanoparticle tracking analysis, flow cytometry, western blotting, BCA protein assay, and ELISA. pSS naïve CD4<sup>+</sup> T cell activation and differentiation treated with EVs isolated from equal volumes of pSS or HC plasma were examined using flow cytometry. miRNA expression profiles of pSS and HC plasma EVs were determined using microRNA (miRNA) sequencing, and upregulated miRNAs in pSS plasma EVs were transfected to naïve CD4<sup>+</sup> T cells, which were examined with activation and differentiation. RNA sequencing of miRNA-transfected naïve CD4<sup>+</sup> T cells combined with miRNA target prediction algorithm identified miRNA target genes, which were confirmed by dual luciferase reporter assay. Tfh cell differentiation of naïve CD4<sup>+</sup> T cells transfected with miRNA and target gene-expressing vector were analyzed using flow cytometry. <h3>Results:</h3> pSS plasma contained more EVs than HC plasma (Figure 1A and B). pSS plasma EVs promoted CD4<sup>+</sup> T cell activation, Th1 and follicular T helper (Tfh) differentiation (Figure 1C and E). miR-501-3p were enriched in pSS plasma EVs (Figure 2A), and promoted CD4<sup>+</sup> T cell activation and Tfh differentiation (Figure 2B and C). Special AT-rich sequence-binding protein-1 (SATB1) was downregulated by miR-501-3p (Figure 2D–E), and overexpressing SATB1 reversed Tfh differentiation promoted by miR-501-3p (Figure 2F). <h3>Conclusion:</h3> Plasma EVs are elevated and promote T cell activation and Tfh differentiation in pSS. pSS plasma EVs contains more miR-501-3p, which downregulates SATB1 to promote Tfh differentiation in pSS (Figure 2G). <h3>REFERENCES:</h3> <b>NIL.</b> <h3>Acknowledgements:</h3> <b>NIL.</b> <h3>Disclosure of Interests:</h3> <b>None declared.</b>
POS0229 THE CHARACTERIZATION OF CIRCULATING EXTRACELLULAR VESICLES AND SMALL NON-CODING RNAS CARGO IN IDIOPATHIC INFLAMMATORY MYOPATHIES REVEALS DIFFERENCES ACROSS CLINICALLY DIAGNOSED MYOSITIS SUBSETS
Authors: M. Gatto, C. Franco, A. Giannella, M. Gasparotto, A. Ghirardello, E. Zanatta, L. Iaccarino, G. Ceolotto, A. Doria
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background:</h3> Extracellular vesicles (EVs) deliver small molecules across several cell types including microRNA (miRNA) which are involved in regulation of gene expression and were proven to play a role in several autoimmune rheumatic diseases. Idiopathic inflammatory myopathies (IIM) display heterogeneity in both phenotype and pathogenic mechanisms which may inform on disease course and prognosis. <h3>Objectives:</h3> To investigate the epigenetic footprint in IIM through characterization of circulating EVs and the expression of EV-derived small non-coding RNAs (sncRNAs). <h3>Methods:</h3> In this cross-sectional study, EVs were isolated by size-exclusion chromatography from plasma of patients with IIM and matched healthy donors (HD). EV-derived sncRNAs were sequenced and quantified using Next-Generation Sequencing (NGS). Following quality control and normalization, filtered count reads were used for differential miRNAs expression analyses. Putative gene targets enriched for pathways implicated in IIM were analyzed. Patients' clinical and laboratory characteristics at the time of sampling were recorded. <h3>Results:</h3> Forty-seven IIM patients and 45 HD were enrolled. We showed a significant upregulation of MiR-486-5p (p&lt;0.01), miR-122-5p, miR-192-5p, and miR-32-5p (p&lt;0.05 for all), while a downregulaion of miR-142-3p (p&lt;0.001), miR-141-3p (p&lt;0.01), let-7a-5p (p&lt;0.05) and miR-3613-5p (p&lt;0.05) in EVs from IIM patients versus HD (Figure 1). MiR-486-5p was associated with increased muscle enzymes levels. Several target genes of up/downregulated miRNAs in IIM participate in inflammation, necroptosis, interferon and immune signaling. Within IIM, miR-335-5p was selectively upregulated and miR-27a-5p downregulated in dermatomyositis (n=21, p&lt;0.01). Plasma EV levels were significantly increased in cancer-associated myositis (CAM, n=12) versus non-CAM IIM (n=35, p=0.02) and HD (p&lt;0.01). EVs cargo in CAM was significantly enriched of let-7f-5p and depleted of miR-143-3p. <h3>Conclusion:</h3> Through an unbiased screening of EV-derived sncRNAs, we show differential patterns of miRNAs expression in the EVs cargo of different IIM subtypes, submitting their role as potential biomarkers and modifiers of diverse IIM phenotypes. <h3>REFERENCES:</h3> <b>NIL.</b> <h3>Acknowledgements:</h3> <b>NIL.</b> <h3>Disclosure of Interests:</h3> Mariele Gatto GSK, AZ, Janssen, Chiara Franco: None declared, Alessandra Giannella: None declared, Michela Gasparotto: None declared, Anna Ghirardello: None declared, Elisabetta Zanatta Janssen, Luca Iaccarino GSK, AZ, GSK, Giulio Ceolotto: None declared, Andrea Doria GSK, AZ, Pfizer, Celgene, Eli Lilly, BMS, Roche, GSK.
POS0122 ANTI-INFLAMMATORY EFFECT OF ATORVASTATIN AND ROSUVASTATIN ON MONOSODIUM URATE-INDUCED INFLAMMATION THROUGH IL-37/SMAD3 COMPLEX ACTIVATION
Authors: S. K. Kim, J. Y. Choe, J. W. Kim, K. Y. Park, B. Kim
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background:</h3> The pleiotropic effect of hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) is responsible for potent defense against inflammatory response. Data on whether HMG-CoA reductase inhibitors affect the immunomodulatory effect of IL-37 are insufficient, although some studies demonstrated that IL-37 could be implicated in the pathogenesis of uric acid-induced inflammation. <h3>Objectives:</h3> This study evaluated the inhibitory effects of HMG-CoA reductase inhibitors on monosodium urate (MSU)-induced inflammatory response through the regulation of interleukin-37 (IL-37) expression. <h3>Methods:</h3> Serum was collected from patients with gout (n = 40) and from healthy controls (n = 30). The mRNA and protein expression of target molecules IL-1β, IL-37, caspase-1, and Smad3 was measured in THP-1 cells stimulated with MSU, atorvastatin, or rosuvastatin using real-time quantitative polymerase chain reaction and Western blot assay. Transfection with IL-1β or Smad3 siRNA in THP-1 cells was used to verify the pharmaceutical effect of statins in uric acid-induced inflammation. <h3>Results:</h3> Serum IL-37 level in gout patients was significantly higher than in controls (p &lt; 0.001) and was associated with serum uric acid level (<i>r</i> = 0.382, p = 0.008). THP-1 cells stimulated with MSU markedly induced IL-37 mRNA expression and transition of IL-37 from cytoplasm to nucleus. Recombinant IL-37 treatment dose-dependently inhibited activation of caspase-1 and IL-1β in MSU-induced inflammation. Atorvastatin and rosuvastatin attenuated caspase-1 activation and mature IL-1β expression but augmented translocation of IL-37 from cytoplasm to nucleus. Atorvastatin and rosuvastatin induced phosphorylation of Smad3 in THP-1 cells treated with MSU crystals. Statins potently attenuated translocation of IL-37 from cytoplasm to nucleus in THP-1 cells transfected with Smad3 siRNA compared to cells with negative control siRNA. <h3>Conclusion:</h3> This study revealed that statins inhibit MSU-induced inflammatory response through augmentation of phosphorylated Smad3-mediated IL-37 expression in THP-1 cells. <h3>REFERENCES:</h3> <b>NIL.</b> <h3>Acknowledgements:</h3> <b>NIL.</b> <h3>Disclosure of Interests:</h3> <b>None declared.</b>