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Dive into the research topics where Aziza Elmesmari is active.

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Featured researches published by Aziza Elmesmari.


Nature Communications | 2016

MicroRNA-155 influences B-cell function through PU.1 in rheumatoid arthritis

Stefano Alivernini; Mariola Kurowska-Stolarska; Barbara Tolusso; Roberta Benvenuto; Aziza Elmesmari; S. Canestri; Luca Petricca; Antonella Mangoni; Anna Laura Fedele; Clara Di Mario; M.R. Gigante; Elisa Gremese; Iain B. McInnes; Gianfranco Ferraccioli

MicroRNA-155 (miR-155) is an important regulator of B cells in mice. B cells have a critical role in the pathogenesis of rheumatoid arthritis (RA). Here we show that miR-155 is highly expressed in peripheral blood B cells from RA patients compared with healthy individuals, particularly in the IgD-CD27- memory B-cell population in ACPA+ RA. MiR-155 is highly expressed in RA B cells from patients with synovial tissue containing ectopic germinal centres compared with diffuse synovial tissue. MiR-155 expression is associated reciprocally with lower expression of PU.1 at B-cell level in the synovial compartment. Stimulation of healthy donor B cells with CD40L, anti-IgM, IL-21, CpG, IFN-α, IL-6 or BAFF induces miR-155 and decreases PU.1 expression. Finally, inhibition of endogenous miR-155 in B cells of RA patients restores PU.1 and reduces production of antibodies. Our data suggest that miR-155 is an important regulator of B-cell activation in RA.


Rheumatology | 2016

MicroRNA-155 regulates monocyte chemokine and chemokine receptor expression in Rheumatoid Arthritis

Aziza Elmesmari; Alasdair R. Fraser; Claire Wood; Derek S. Gilchrist; Diane Vaughan; Lynn Stewart; Charles McSharry; Iain B. McInnes; Mariola Kurowska-Stolarska

Objective. To test the hypothesis that miR-155 regulates monocyte migratory potential via modulation of chemokine and chemokine receptor expression in RA, and thereby is associated with disease activity. Methods. The miR-155 copy-numbers in monocytes from peripheral blood (PB) of healthy (n = 22), RA (n = 24) and RA SF (n = 11) were assessed by real time-PCR using synthetic miR-155 as a quantitative standard. To evaluate the functional impact of miR-155, human monocytes were transfected with control or miR-155 mimic, and the effect on transcript levels, and production of chemokines was evaluated by Taqman low-density arrays and multiplex assays. A comparative study evaluated constitutive chemokine receptor expression in miR-155−/− and wild-type murine (CD115 + Ly6C + Ly6G−) monocytes. Results. Compared with healthy monocytes, the miR-155 copy-number was higher in RA, peripheral blood (PB) and SF monocytes (PB P < 0.01, and SF P < 0.0001). The miR-155 copy-number in RA PB monocytes was higher in ACPA-positive compared with ACPA-negative patients (P = 0.033) and correlated (95% CI) with DAS28 (ESR), R = 0.728 (0.460, 0.874), and with tender, R = 0.631 (0.306, 0.824) and swollen, R = 0.503 (0.125, 0.753) joint counts. Enforced-expression of miR-155 in RA monocytes stimulated the production of CCL3, CCL4, CCL5 and CCL8; upregulated CCR7 expression; and downregulated CCR2. Conversely, miR155−/− monocytes showed downregulated CCR7 and upregulated CCR2 expression. Conclusion. Given the observed correlations with disease activity, these data provide strong evidence that miR-155 can contribute to RA pathogenesis by regulating chemokine production and pro-inflammatory chemokine receptor expression, thereby promoting inflammatory cell recruitment and retention in the RA synovium.


Nature Communications | 2017

MicroRNA-34a dependent regulation of AXL controls the activation of dendritic cells in inflammatory arthritis

Mariola Kurowska-Stolarska; Stefano Alivernini; Emma Garcia Melchor; Aziza Elmesmari; Barbara Tolusso; Clare Tange; Luca Petricca; Derek S. Gilchrist; Gabriele Di Sante; Chantal Keijzer; Lynn Stewart; Clara Di Mario; Vicky L. Morrison; James M. Brewer; Duncan Porter; Simon Milling; Ronald D. Baxter; David McCarey; Elisa Gremese; Greg Lemke; Gianfranco Ferraccioli; Charles McSharry; Iain B. McInnes

Current treatments for rheumatoid arthritis (RA) do not reverse underlying aberrant immune function. A genetic predisposition to RA, such as HLA-DR4 positivity, indicates that dendritic cells (DC) are of crucial importance to pathogenesis by activating auto-reactive lymphocytes. Here we show that microRNA-34a provides homoeostatic control of CD1c+ DC activation via regulation of tyrosine kinase receptor AXL, an important inhibitory DC auto-regulator. This pathway is aberrant in CD1c+ DCs from patients with RA, with upregulation of miR-34a and lower levels of AXL compared to DC from healthy donors. Production of pro-inflammatory cytokines is reduced by ex vivo gene-silencing of miR-34a. miR-34a-deficient mice are resistant to collagen-induced arthritis and interaction of DCs and T cells from these mice are reduced and do not support the development of Th17 cells in vivo. Our findings therefore show that miR-34a is an epigenetic regulator of DC function that may contribute to RA.


Journal of Immunology | 2018

ILDR2 Is a Novel B7-like Protein That Negatively Regulates T Cell Responses

Iris Hecht; Amir Toporik; Joseph R. Podojil; Ilan Vaknin; Gady Cojocaru; Anat Oren; Elizabeta Aizman; Spencer Liang; Ling Leung; Yosef Dicken; Amit Novik; Nadav Marbach-Bar; Aziza Elmesmari; Clare Tange; Ashley Gilmour; Donna McIntyre; Mariola Kurowska-Stolarska; Kay McNamee; Judith Leitner; Shirley Greenwald; Liat Dassa; Zurit Levine; Peter Steinberger; Richard O. Williams; Stephen D. Miller; Iain B. McInnes; Eyal Neria; Galit Rotman

The B7-like protein family members play critical immunomodulatory roles and constitute attractive targets for the development of novel therapies for human diseases. We identified Ig-like domain–containing receptor (ILDR)2 as a novel B7-like protein with robust T cell inhibitory activity, expressed in immune cells and in immune-privileged and inflamed tissues. A fusion protein, consisting of ILDR2 extracellular domain with an Fc fragment, that binds to a putative counterpart on activated T cells showed a beneficial effect in the collagen-induced arthritis model and abrogated the production of proinflammatory cytokines and chemokines in autologous synovial-like cocultures of macrophages and cytokine-stimulated T cells. Collectively, these findings point to ILDR2 as a novel negative regulator for T cells, with potential roles in the development of immune-related diseases, including autoimmunity and cancer.


Frontiers in Immunology | 2017

Sphingosine-1-phosphate promotes the persistence of activated CD4 T cells in inflamed sites

Shafqat Ahrar Jaigirdar; Robert A. Benson; Aziza Elmesmari; Mariola Kurowska-Stolarska; Iain B. McInnes; Paul Garside; Megan K. L. MacLeod

Inflammation can be protective or pathogenic depending on context and timeframe. Acute inflammation, including the accumulation of CD4 T cells, accompanies protective immune responses to pathogens, but the presence of activated CD4 T cells at sites of inflammation is associated with chronic inflammatory disease. While significant progress has been made in understanding the migration of CD4 T cells into inflamed sites, the signals that lead to their persistence are poorly characterized. Using a murine ear model of acute inflammation and intravital two-photon imaging, we have dissected the signals that mediate CD4 T cell persistence. We report the unexpected finding that the bioactive lipid, sphingosine-1-phosphate (S1P), is both necessary and sufficient for the persistence of activated CD4 T cells at peripheral tissues in acute inflammation. S1P mediated the enhanced motility of CD4 T cells at inflamed tissues but did not affect their migration to the downstream draining lymph node. We found that sphingosine kinase-1, which regulates S1P production is increased at inflamed sites in mice and in patients with the chronic inflammatory disease, rheumatoid arthritis. Together, these data suggest that S1P, or its regulators, may be key targets to promote or disrupt accumulation of CD4 T cells at inflamed tissues.


Annals of the Rheumatic Diseases | 2017

03.13 Synovial tissue of ra patients in remission contains a unique population of regulatory macrophages

Aziza Elmesmari; Stefano Alivernini; Barbara Tolusso; Diane Vaughan; Gabriele Di Sante; Luca Petricca; Elisa Gremese; Gianfranco Ferraccioli; Iain B. McInnes; Mariola Kurowska-Stolarska

Objectives The majority of RA treatments target inflammation or the adaptive immune response. Partial- or non-response is common and only a minority have sustained remission. There is a knowledge gap in understanding the mechanisms that could reinstate synovial homeostasis in RA. Tissue macrophages may have a role in this process; they are present in healthy synovium and aid resolution of the inflammation in experimental models of RA. However, little is known about the regulatory properties of human synovial tissue macrophages. Our hypothesis is that healthy and RA synovium in remission contain macrophages with anti-inflammatory/repair properties and identifying the effector pathways that drive their function could facilitate therapeutic restoration of synovial homeostasis in RA. Methods and materials We developed a flow cytometry sorting strategy for harvesting tissue-resident macrophages obtained from digested synovial biopsies of RA patients (n=21, including in remission n=5; and active RA n=16). Cells were labelled with cell lineage specific antibodies; and then macrophages were gated based on their expression of CD64posCD11bposMHCIIposLineageneg. The potential homeostatic/repair macrophage was preliminary identified by the presence of CD206 marker. CD206pos and CD206neg macrophages were sorted using a FACS Aria III and RNAseq preformed to characterise their functional signature. In some experiment, macrophages were seeded on collagen-coated plates and production of TNFα evaluated. Results All synovial tissue macrophages from RA in remission were CD206pos whereas a substantial number of synovial macrophages from active RA tissue were CD206neg. Gene expression analyses and functional assays suggest that these populations represent distinct phenotypes in the activation spectrum. CD206neg macrophages have high expression of microRNA-155, which drives production of inflammatory mediators eg, TNFα. In contrast, CD206pos macrophages showed regulatory properties characterised by increased expression of soluble (eg, IL10, TGFB), surface (eg, IL4/14 R, TGFBR1/2) and cellular (eg, SHIP1, TAM, SMAD2, STAT6) inhibitors of inflammatory activation, and increased expression of repair markers (eg, ARG2 and CCL18). Conclusions We propose therefore that anti-inflammatory/repair macrophages may be present in human synovial tissues in remission representing a hitherto unnoticed regulatory tissue mechanism.


Archive | 2012

The role of SPHKs and SIPRs in rheumatoid arthritis

Aziza Elmesmari; Peter Natesan Pushparaj; James H. Reilly; Shauna Kerr; Mariola Kurowska-Stolarska; Iain B. McInnes

Background: Polyvalent vaccination represents a recent attempt to improve the effectiveness of lung cancer immunotherapy. This study aimed to investigate whether a gene expression pattern of tumor-associated antigens (TAA) would exist indicating that their use will be most appropriate for the polyvalent vaccination of Caucasian non-small cell lung carcinoma (NSCLC) patients. We examined the concomitant expression of genes belonging to different TAA families for which expression frequencies either have never been detected in NSCLC or vary widely in the literature. Methods: Tumor material from 23 patients with NSCLC (12 adenocarcinomas, 8 squamous cell carcinomas, 3 bronchoalveolar carcinomas) was examined. mRNA transcripts were detected for 5 genes of the survivin family, 5 MAGE-A genes as well as the genes of human telomerase reverse transcriptase (hTERT) and p53, by the use of quantitative real-time reverse-transcription polymerase chain reaction (RT-PCR) or semiquantitative RT-PCR. Results: 15/23 (65%) and 8/23 (35%) tumor samples were found expressing 6-11 and 2-5 out of the 12 examined TAAs, respectively, at levels >1% of the testis reference sample. The most prevalent TAA patterns observed were those of survivin standard (survivinstd)/survivin-2B expressed by 22/23 (95.5%) tumor samples and of survivin-std/survivin-2B/hTERT expressed by 19/23 (82.5%) tumor samples. The expression levels of the survivin-std gene strongly positively correlated to those of the survivin-2B (p=0.001) and the hTERT genes (p=0.031). The number of concomitantly expressed genes was found to be positively correlated to the age of the patients (p=0.001) and the tumor size (p=0.048). Conclusion: This study provides evidence that, in Caucasian patients with NSCLC, highly prevalent expression patterns of TAA genes, predominantly of overexpressed TAAs, do exist. This result implies that the combined use of these TAA could help in designing more effective NSCLC immunotherapeutic protocols.Purpose/Objective: Rheumatoid arthritis (RA) is a chronic autoimmune disease that leads to joint destruction. The recruitment of effectors cells, including monocytes to the joint space is an important step in RA progression and is mediated by chemokines (Ch) and their receptors (ChR). MicroRNAs are a recently discovered class of posttranscriptional regulators. Many members of the miR family are implicated in the regulation of cell movement and migration. Our previous study showed miR-155 is upregulated in RA synovial fluid (SF) monocytes suggesting that this miR may be involved in activation of these cells, including their migration into joint space. We hypothesized that miR-155 could regulates migration of monocytes in RA by modulating the expression of the chemokine and chemokine receptor system. Materials and methods: Peripheral blood (PB) CD14+ cells from healthy controls (HC) and RA patients were transfected with miR-155 mimic or scramble mimic using N-TER nanoparticles and cultured for 48 h. TaQman Low Density Array and multiplex assay was used to evaluate ChR expression and Ch production, respectively. Similar analysis was carried out on bone marrow monocytes (BMM) from miR-155-/- and WT mice. In addition, absolute copy numbers of miR- 155 transcripts in PB and SF CD14+ of RA and HC were assessed by QPCR. Results: PB and SF monocytes in RA patients showed higher copy number of miR-155 compared to HC. Overexpression of miR-155 in HC and RA monocytes did not affect the production of CCL2, CCL7, CCL21, CXCL5, CXCL8, CXCL7, CXCL10 and CX3CL1. In contrast, overexpression of miR-155 induced the production of chemokines such as CCL4, CCL5 and CCL22 in RA monocytes and CCL3 in both RA and HC. Analysis of chemokine receptors in BMM of miR-155-/- and WT mice revealed significantly higher levels of CCR1, CCR2, CCR5 and CXCR4 in miR-155 deficient cells suggesting that miR-155 can act as a negative regulator of these receptors in homeostatic state. As expected, TLR-4 ligand significantly suppressed expression of these receptors in both WT and miR-155-/- cells. Analysis of 3’UTRs of Ch/ ChR (TargetScan) suggests that miR-155 is likely interfering with signaling pathways implicated in Ch/ChR system expression. Conclusions: Deregulation of miR-155 in RA monocytes can contribute to the production of pro-inflammatory chemokines by these cells and to their accumulation at sites of inflammation.Purpose/Objective: Sphingosine kinase (SPHKs), SphK1 and SphK2, have been identified to phosphorylate sphingosine into sphingosine-1- phosphate (S1P). They are involved in a wide variety of cellular responses. S1P acts via S1P Receptors, S1PR1, S1PR2, S1PR3, S1PR4 and S1PR5, all of which can be bound and activated specifically by S1P. A defect either in S1P signalling or S1PRs has been associated with many pathologies. Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by high levels of proinflammatory cytokine production. Elevated SPHK1, S1P, and S1P1 have been reported in RA synovium. S1P signalling via S1P1 promotes synoviocyte proliferation, increases COX-2 expression and prostaglandin E2 production. This study comprehensively evaluated expression of SPHK1/2 and S1PRs in RA patients compare to healthy controls (HC) and osteoarthritis (OA) in peripheral blood (PB) and synovial tissues, respectively. Materials and methods: mRNA and protein expression of SPHK1/2 and SIPRs were examined in neutrophils, monocytes and T lymphocytes of peripheral blood of 10 HC and RA patients, who met the diagnostic criteria of 2010 ARC / EULAR by QPCR and FACS, respectively. Competitive ELISA assessed SIP in serum of RA patients with remission and relapse and HC. We also performed SPHK 1/2 and SIPRs immunohistochemistry in synovial tissue from 4 RA/ OA patients. Results: S1P was three times high in RA than those observed in HC, also was statistically higher in RA patient with relapse than remission. Intracellular expression of hSPHK1 in RA patients, with opposed to HC, was up regulated 1.4-folds in monocytes and T- lymphocytes with significance expression in CD4T cells. hS1P1 and hS1P3 exhibited a similar expression were up-regulated in neutrophils, while, hS1P5 was statistical high in T cells. In contrast, hS1P4 was down regulated in all sorted cells particularly in CD4T cells. As opposed to OA synovial tissue, RA synovial tissues were strongly positive for hSPHK1 and hS1P1, 3 expressions. Quantitative analysis showed, SPHK1 and hS1P3 are expressed in lining, sub lining and vascular endothelial layer, while hS1P1 expressed mainly in lining and sub lining layers of the RA synovial tissue compared with OA. Conclusions: These results suggest that SPHKs/S1P and its S1PRs might play a role in RA pathogenesis. The clinical significance of S1P as a biomarker for disease activity deserves further attention.


Archive | 2012

The role of miR-155 in monocyte migration in Rheumatoid arthritis

Aziza Elmesmari; Derek S. Gilchrist; Alasdair R. Fraser; James M. Brewer; Iain B. McInnes; Mariola Kurowska-Stolarska

Background: Polyvalent vaccination represents a recent attempt to improve the effectiveness of lung cancer immunotherapy. This study aimed to investigate whether a gene expression pattern of tumor-associated antigens (TAA) would exist indicating that their use will be most appropriate for the polyvalent vaccination of Caucasian non-small cell lung carcinoma (NSCLC) patients. We examined the concomitant expression of genes belonging to different TAA families for which expression frequencies either have never been detected in NSCLC or vary widely in the literature. Methods: Tumor material from 23 patients with NSCLC (12 adenocarcinomas, 8 squamous cell carcinomas, 3 bronchoalveolar carcinomas) was examined. mRNA transcripts were detected for 5 genes of the survivin family, 5 MAGE-A genes as well as the genes of human telomerase reverse transcriptase (hTERT) and p53, by the use of quantitative real-time reverse-transcription polymerase chain reaction (RT-PCR) or semiquantitative RT-PCR. Results: 15/23 (65%) and 8/23 (35%) tumor samples were found expressing 6-11 and 2-5 out of the 12 examined TAAs, respectively, at levels >1% of the testis reference sample. The most prevalent TAA patterns observed were those of survivin standard (survivinstd)/survivin-2B expressed by 22/23 (95.5%) tumor samples and of survivin-std/survivin-2B/hTERT expressed by 19/23 (82.5%) tumor samples. The expression levels of the survivin-std gene strongly positively correlated to those of the survivin-2B (p=0.001) and the hTERT genes (p=0.031). The number of concomitantly expressed genes was found to be positively correlated to the age of the patients (p=0.001) and the tumor size (p=0.048). Conclusion: This study provides evidence that, in Caucasian patients with NSCLC, highly prevalent expression patterns of TAA genes, predominantly of overexpressed TAAs, do exist. This result implies that the combined use of these TAA could help in designing more effective NSCLC immunotherapeutic protocols.Purpose/Objective: Rheumatoid arthritis (RA) is a chronic autoimmune disease that leads to joint destruction. The recruitment of effectors cells, including monocytes to the joint space is an important step in RA progression and is mediated by chemokines (Ch) and their receptors (ChR). MicroRNAs are a recently discovered class of posttranscriptional regulators. Many members of the miR family are implicated in the regulation of cell movement and migration. Our previous study showed miR-155 is upregulated in RA synovial fluid (SF) monocytes suggesting that this miR may be involved in activation of these cells, including their migration into joint space. We hypothesized that miR-155 could regulates migration of monocytes in RA by modulating the expression of the chemokine and chemokine receptor system. Materials and methods: Peripheral blood (PB) CD14+ cells from healthy controls (HC) and RA patients were transfected with miR-155 mimic or scramble mimic using N-TER nanoparticles and cultured for 48 h. TaQman Low Density Array and multiplex assay was used to evaluate ChR expression and Ch production, respectively. Similar analysis was carried out on bone marrow monocytes (BMM) from miR-155-/- and WT mice. In addition, absolute copy numbers of miR- 155 transcripts in PB and SF CD14+ of RA and HC were assessed by QPCR. Results: PB and SF monocytes in RA patients showed higher copy number of miR-155 compared to HC. Overexpression of miR-155 in HC and RA monocytes did not affect the production of CCL2, CCL7, CCL21, CXCL5, CXCL8, CXCL7, CXCL10 and CX3CL1. In contrast, overexpression of miR-155 induced the production of chemokines such as CCL4, CCL5 and CCL22 in RA monocytes and CCL3 in both RA and HC. Analysis of chemokine receptors in BMM of miR-155-/- and WT mice revealed significantly higher levels of CCR1, CCR2, CCR5 and CXCR4 in miR-155 deficient cells suggesting that miR-155 can act as a negative regulator of these receptors in homeostatic state. As expected, TLR-4 ligand significantly suppressed expression of these receptors in both WT and miR-155-/- cells. Analysis of 3’UTRs of Ch/ ChR (TargetScan) suggests that miR-155 is likely interfering with signaling pathways implicated in Ch/ChR system expression. Conclusions: Deregulation of miR-155 in RA monocytes can contribute to the production of pro-inflammatory chemokines by these cells and to their accumulation at sites of inflammation.Purpose/Objective: Sphingosine kinase (SPHKs), SphK1 and SphK2, have been identified to phosphorylate sphingosine into sphingosine-1- phosphate (S1P). They are involved in a wide variety of cellular responses. S1P acts via S1P Receptors, S1PR1, S1PR2, S1PR3, S1PR4 and S1PR5, all of which can be bound and activated specifically by S1P. A defect either in S1P signalling or S1PRs has been associated with many pathologies. Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by high levels of proinflammatory cytokine production. Elevated SPHK1, S1P, and S1P1 have been reported in RA synovium. S1P signalling via S1P1 promotes synoviocyte proliferation, increases COX-2 expression and prostaglandin E2 production. This study comprehensively evaluated expression of SPHK1/2 and S1PRs in RA patients compare to healthy controls (HC) and osteoarthritis (OA) in peripheral blood (PB) and synovial tissues, respectively. Materials and methods: mRNA and protein expression of SPHK1/2 and SIPRs were examined in neutrophils, monocytes and T lymphocytes of peripheral blood of 10 HC and RA patients, who met the diagnostic criteria of 2010 ARC / EULAR by QPCR and FACS, respectively. Competitive ELISA assessed SIP in serum of RA patients with remission and relapse and HC. We also performed SPHK 1/2 and SIPRs immunohistochemistry in synovial tissue from 4 RA/ OA patients. Results: S1P was three times high in RA than those observed in HC, also was statistically higher in RA patient with relapse than remission. Intracellular expression of hSPHK1 in RA patients, with opposed to HC, was up regulated 1.4-folds in monocytes and T- lymphocytes with significance expression in CD4T cells. hS1P1 and hS1P3 exhibited a similar expression were up-regulated in neutrophils, while, hS1P5 was statistical high in T cells. In contrast, hS1P4 was down regulated in all sorted cells particularly in CD4T cells. As opposed to OA synovial tissue, RA synovial tissues were strongly positive for hSPHK1 and hS1P1, 3 expressions. Quantitative analysis showed, SPHK1 and hS1P3 are expressed in lining, sub lining and vascular endothelial layer, while hS1P1 expressed mainly in lining and sub lining layers of the RA synovial tissue compared with OA. Conclusions: These results suggest that SPHKs/S1P and its S1PRs might play a role in RA pathogenesis. The clinical significance of S1P as a biomarker for disease activity deserves further attention.


Archive | 2012

Microrna-155 regulates chemokines and chemokine receptors in Rheumatoid Arthritis monocyte

Aziza Elmesmari; Derek S. Gilchrist; Alasdair D. Fraser; Diane Vaughan; Ross McQueenie; Gerard J. Graham; James M. Brewer; Iain B. McInnes; Mariola Kurowska-Stolarska

Background/Purpose: MicroRNAs (miRs) are a novel class of posttranscriptional regulators. A single miR can have profound effects on cell activation due to its ability to modulate multiple pathways at once. We have previously shown that miR-155 is upregulated in rheumatoid arthritis (RA) synovial macrophages and promotes the development of autoimmunity and joint inflammation. Pre-clinical arthritis may be associated with lung changes e.g. bronchial wall thickening, thus the aim of this study was to investigate the contribution of miR-155 regulated pathways to lung homeostasis. Methods: Normal human lung tissue was tested by in situ hybridisation with miR-155 and control probes. To model the fibrotic response, WT and miR-155 / mice were given bleomycin (0.06 unit/mouse) intranasally. Intervention included intraperitoneal injections of the Liver X Receptor (LXR) agonist (GW3965 daily; 40 mg/kg). End-points included bronchial lavage (BAL) cytology, lung tissue histology, evaluation of the expression of inflammatory and fibrotic genes by qPCR and concentrations of soluble mediators in serum and BAL fluid by multiplex assays. The validation of miR-155 binding to LXR, and the LXR response element in collagen gene promoters were performed with reporter assays. Results: In situ hybridisation showed an abundant expression of miR-155 in the normal human lung suggesting that this miR may contribute to normal lung homeostasis. miR-155 / mice developed more severe bleomycininduced lung fibrosis compared to WT mice, as seen by increased collagen 1a/3a mRNA expression and protein deposition in the lungs, as well as accumulation of macrophages and lymphocytes in BAL. Gene expression analysis of lung extracts revealed an increase in the M2 pro-fibrotic macrophage markers Arginase 2, IL-13R and Ym1. In addition, the levels of pro-fibrotic cytokines such as VEGF and bFGF were significantly higher in BAL and serum of miR-155 / mice. Primary lung fibroblast lines derived from miR-155 / mice showed higher proliferation rates and motility compared to WT cells in wound healing assays. Computational analysis followed by functional luciferase assays revealed that the transcription activator LXR alpha is a direct target of miR-155 in the lungs. Expression of LXR alpha was significantly upregulated in the lungs of naive miR-155 / mice and was further increased in mice given bleomycin compared to similarly treated WT controls. Injection of the LXR agonist to WT mice increased LXR expression and mirrored the same phenotypic response to bleomycin as the miR-155 deficient mice; shown by increased collagen deposition and M2 macrophage and fibroblast activation. Promoter analysis revealed that LXRs could directly induce collagen production by binding to col1a and col3a promoters. / Conclusion: miR-155 appears important for lung homeostasis, likely by fine tuning levels of LXR thereby protecting from excessive remodelling. Given this and the emerging contribution of miR-155 to development of autoimmunity, this miR may act as a master-switch determining the duration of inflammation and the initiation of remodelling, as well as the balance between the immune and auto-immune responses.Background/Purpose: High mobility group box 1 (HMGB1) is a non-histone DNA binding protein that is passively released by dying cells or actively secreted by immunocompetent cells and the receptor for advanced glycation end-products (RAGE) is one of its receptors. Higher levels of HMGB1 have been found in patients with granulomatosis with polyangiitis (GPA) with active disease whereas higher HMGB1 and lower soluble (sRAGE) levels have been found in patients with acute atherosclerotic events suggesting sRAGE acts as a decoy receptor. This study aims to evaluate HMGB1 levels in relation to subclinical carotid atherosclerosis in GPA, and the impact of therapy on HMGB1 levels. Methods: A cross-sectional study was performed on 23 GPA patients during a quiescent phase of the disease in comparison to 20 matched controls. All study participants underwent carotid ultrasound to assess atherosclerotic plaques and intima-media thickness (IMT) and were tested for traditional risk factors for atherosclerosis, serum HMGB1 levels (ELISA-Shino Test, Kanagawa, Japan), and sRAGE levels (ELISA RD P = 0.978), HDLcholesterol (1.41 ± 0.37 vs. 1.51±0.33 mmol/L; P = 0.359), LDLcholesterol (3.01±0.79 vs. 3.29±0.82 mmol/L; P = 0.267), and a similar frequency of smoking (8.7% vs. 5.0%; P = 0.635), family history of premature coronary artery disease (CAD) (39.1% vs. 40.0%; P = 0.954), and obesity (4.3% vs. 10.0%; P = 0.446). Hypertension was only found in GPA patients (39.1% vs. 0.0%; P = 0.002) while no study participants had diabetes. Overt cardiovascular disease was found only in 13.0% of GPA patients. Statins were prescribed for 21.7% of GPA patients and 5.0% of controls (P = 0.127). Among GPA patients, prednisolone was being used by 34.8% with a median daily dose of 5.0mg (2.5-15.0) and azathioprine by 34.8%. Only two GPA patients used statins and prednisolone concomitantly. Carotid plaques were found in 30.4% of GPA patients and in 15.0% of controls (P = 0.203) and the overall IMT was similar in GPA patients and in controls (0.833±0.256 vs. 0.765±0.133mm; P = 0.861). Median serum HMGB1 levels were similar between GPA patients and controls [2.13ng/mL (1.11-7.22) vs. 2.42ng/mL (0.38-6.75); P = 0.827] as well as mean sRAGE levels (1256.1±559.6 vs. 1483.3±399.8pg/mL; P = 0.155). No correlations were found between HMGB1 and sRAGE ( = 0.068; P = 0.681) and between HMGB1 and maximum IMT in carotid arteries ( = -0.067; P = 0.720). GPA patients on prednisolone (1.77±0.76 vs. 3.53±2.06ng/ mL; P = 0.017) and statins (1.39±0.28 vs. 3.34±1.94ng/mL; P = 0.001) presented significantly lower serum HMGB1 levels whereas no difference in mean HMGB1 levels was found regarding azathioprine use (2.89±2.28 vs. 2.93±1.75; P = 0.970). Conclusion: No association was found between subclinical atherosclerosis in carotid arteries and HMGB1 levels in GPA patients. Furthermore, the use of either prednisone or statins was associated with lower HMGB1 levels in GPA patients. These findings suggest that the anti-inflammatory properties of statins include effects on serum HMGB1 levels in GPA.


Rheumatology | 2017

RHEUMATOID ARTHRITIS: PATHOGENESIS204. CHARACTERIZATION OF SYNOVIUM TISSUES MACROPHAGE OF RHEUMATOID ARTHRITIS PATIENTS

Aziza Elmesmari; Stefano Alivernini; Diane Vaughan; Gianfranco Ferraccioli; Iain B. McInnes; Mariola Kurowska-Stolarska

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Gianfranco Ferraccioli

Catholic University of the Sacred Heart

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Stefano Alivernini

Catholic University of the Sacred Heart

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Barbara Tolusso

Catholic University of the Sacred Heart

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Elisa Gremese

Catholic University of the Sacred Heart

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Luca Petricca

Catholic University of the Sacred Heart

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