Rheumatoid Arthritis: Filer A

Raza K, Filer A. · Rheumatology Research Group, Division of Immunity and Infection, Institute of Biomedical Research, MRC Centre for Immune Regulation, University of Birmingham, Birmingham, UK. · Best Pract Res Clin Rheumatol. · Pubmed #19233043 No free full text.

Abstract: The rapidity with which bone and cartilage damage occurs in patients with rheumatoid arthritis (RA), and the increasing body of evidence for the effectiveness of early intervention in RA, mean that there is a great need for approaches to accurately predict the development of RA in patients with early undifferentiated arthritis. We will review developments in the prediction of outcome on the basis of clinical and laboratory features, including measures of anti-citrullinated protein/peptide antibody status. Although accurate predictions are possible in the majority of patients using recently developed predictive algorithms which utilize clinical and serological variables, there remains a group of patients for whom it is very difficult to predict the development of RA. The utility of new strategies for prediction will be discussed, including recently discovered genetic associations of RA, an assessment of material from the primary site of pathology (the joint), and assessment using the highly sensitive imaging modalities of ultrasound and magnetic resonance imaging.

Filer A, Raza K, Salmon M, Buckley CD. · Rheumatology Research Group, MRC Centre for Immune regulation, Division of Immunity and Infection, The University of Birmingham, Birmingham, UK. · Front Biosci. · Pubmed #17981742 No free full text.

Abstract: New dimensions in our understanding of immune cell trafficking in health and disease have been opened by the discovery of chemokines and their receptors. This family of chemo-attractant cytokines performs essential roles in the recruitment and subsequent positioning of leucocyte subsets within tissue microenvironments. Investigation of chemokine networks offers a novel approach to understand the mechanisms by which inflammatory cells persist in diseases such as rheumatoid arthritis (RA), where evidence is mounting that the inappropriate temporal and spatial expression of chemokines and/or their receptors may impair the resolution of leucocyte infiltrates. The recognition that stromal cells such as fibroblasts, as active components of tissue specific microenvironments, are able to determine the type and persistence of inflammatory infiltrates has opened new vistas in research. Stromal cells are active contributors to cytokine and inflammatory chemokine networks which result in immune cell recruitment and activation. However an intriguing role of stromal cells has been demonstrated in the inappropriate expression of constitutive, housekeeping chemokines, which contribute to the persistence of inflammation by actively blocking its resolution.

Burman A, Haworth O, Bradfield P, Parsonage G, Filer A, Thomas AM, Amft N, Salmon M, Buckley CD. · Rheumatology Research Group, Institute for Biomedical Research, Division of Immunity and Infection, MRC Centre for Immune Regulation, University of Birmingham, Birmingham B15 2TT, UK. · Joint Bone Spine. · Pubmed #15681242 No free full text.

Abstract: Rheumatoid arthritis (RA) is a debilitating, chronic, persistent inflammatory disease that is characterised by painful and swollen joints. The aetiology of RA is unknown, however whereas past research has concentrated on the role of immune or inflammatory infiltrating cells in inflammation, it is becoming clear that stromal cells play a critical part in regulating the quality and duration of an inflammatory response. In this review we assess the role of fibroblasts within the inflamed synovium in modulating immune responses; in particular we examine the role of stromal cells in the switch from resolving to persistent inflammation as is found in the rheumatoid synovium.

Buckley CD, Filer A, Haworth O, Parsonage G, Salmon M. · Department of Rheumatology, Division of Immunity and Infection, University of Birmingham, Birmingham, B15 2TT, UK. · Ann Rheum Dis. · Pubmed #15479882 links to  free full text

Abstract: The most surprising feature of the inflammatory response in rheumatoid arthritis is not that it occurs but that it does not resolve. The persistence of the chronic inflammatory response in conjunction with ongoing joint destruction is an all too familiar finding in many patients with rheumatoid arthritis. Despite the use of effective anti-inflammatory agents and disease modifying drugs, a significant proportion of patients with rheumatoid arthritis continue to have resistant disease. Complete clinical remission is unusual for more than six months and a formal cure of the disease remains elusive. In this report we focus on how attempts to address the question of why rheumatoid arthritis persists have led to a different interpretation of the pathogenesis of rheumatoid disease; one in which alterations in stromal cells such as fibroblasts play an important role in the switch from resolving to persistent disease.

Filer A, Bik M, Parsonage GN, Fitton J, Trebilcock E, Howlett K, Cook M, Raza K, Simmons DL, Thomas AM, Salmon M, Scheel-Toellner D, Lord JM, Rabinovich GA, Buckley CD. · University of Birmingham, Division of Immunity and Infection, Birmingham, UK. · Arthritis Rheum. · Pubmed #19479862 No free full text.

Abstract: OBJECTIVE: High expression of galectin 3 at sites of joint destruction in rheumatoid arthritis (RA) suggests that galectin 3 plays a role in RA pathogenesis. Previous studies have demonstrated the effects of galectins on immune cells, such as lymphocytes and macrophages. This study was undertaken to investigate the hypothesis that galectin 3 induces proinflammatory effects in RA by modulating the pattern of cytokine and chemokine production in synovial fibroblasts. METHODS: Matched samples of RA synovial and skin fibroblasts were pretreated with galectin 3 or tumor necrosis factor alpha (TNFalpha), and the levels of a panel of cytokines, chemokines, and matrix metalloproteinases (MMPs) were determined using enzyme-linked immunosorbent assays and multiplex assays. Specific inhibitors were used to dissect signaling pathways, which were confirmed by Western blotting and NF-kappaB activation assay. RESULTS: Galectin 3 induced secretion of interleukin-6 (IL-6), granulocyte-macrophage colony-stimulating factor, CXCL8, and MMP-3 in both synovial and skin fibroblasts. By contrast, galectin 3-induced secretion of TNFalpha, CCL2, CCL3, and CCL5 was significantly greater in synovial fibroblasts than in skin fibroblasts. TNFalpha blockade ruled out autocrine TNFalpha-stimulated induction of chemokines. The MAPKs p38, JNK, and ERK were necessary for IL-6 production, but phosphatidylinositol 3-kinase (PI 3-kinase) was required for selective CCL5 induction. NF-kappaB activation was required for production of both IL-6 and CCL5. CONCLUSION: Our findings indicate that galectin 3 promotes proinflammatory cytokine secretion by tissue fibroblasts. However, galectin 3 induces the production of mononuclear cell-recruiting chemokines uniquely from synovial fibroblasts, but not matched skin fibroblasts, via a PI 3-kinase signaling pathway. These data provide further evidence of the role of synovial fibroblasts in regulating the pattern and persistence of the inflammatory infiltrate in RA and suggest a new and important functional consequence of the observed high expression of galectin 3 in the rheumatoid synovium.

McGettrick HM, Smith E, Filer A, Kissane S, Salmon M, Buckley CD, Rainger GE, Nash GB. · Centre for Cardiovascular Sciences, The Medical School, The University of Birmingham, Birmingham, UK. · Eur J Immunol. · Pubmed #19130557 No free full text.

Abstract: We examined the hypothesis that stromal fibroblasts modulate the ability of endothelial cells (EC) to recruit lymphocytes in a site-specific manner. PBL were perfused over HUVEC that had been cultured with fibroblasts isolated from the inflamed synovium or the skin of patients with rheumatoid arthritis or osteoarthritis, or from normal synovium, with or without exposure to the inflammatory cytokines TNF-alpha+IFN-gamma. Fibroblasts from inflamed synovium, but no others, caused unstimulated HUVEC to bind flowing lymphocytes. This adhesion was supported by alpha(4)beta(1)-VCAM-1 interaction and stabilised by activation of PBL through CXCR4-CXCL12. Antibody neutralisation of IL-6 during co-culture effectively abolished the ability of EC to bind lymphocytes. Cytokine-stimulated EC supported high levels of lymphocyte adhesion, through the presentation of VCAM-1, E-selectin and chemokine(s) acting through CXCR3. Interestingly, co-culture with dermal fibroblasts caused a marked reduction in cytokine-induced adhesion, while synovial fibroblasts had variable effects depending on their source. In the dermal co-cultures, neutralisation of IL-6 or TGF-beta caused partial recovery of cytokine-induced lymphocyte adhesion; this was complete when both were neutralised. Exogenous IL-6 was also found to inhibit response to TNF-alpha+IFN-gamma. Normal stromal fibroblasts appear to regulate the cytokine-sensitivity of vascular endothelium, while fibroblasts associated with chronic inflammation bypass this and develop a directly inflammatory phenotype. Actions of IL-6 might be pro-inflammatory or anti-inflammatory, depending on the local milieu.

van der Helm-van Mil AH, Detert J, le Cessie S, Filer A, Bastian H, Burmester GR, Huizinga TW, Raza K. · Department of Rheumatology, Leiden University Medical Center, Leiden, The Netherlands. <> · Arthritis Rheum. · Pubmed #18668546 links to  free full text

Abstract: OBJECTIVE: The decision to start disease-modifying antirheumatic drugs in patients with recent-onset undifferentiated arthritis (UA) is complicated by a varied natural disease course in which the disease in one-third of patients progresses to rheumatoid arthritis (RA), whereas 40-50% of patients experience spontaneous remission. Recently, a prediction rule was developed to estimate the chance of progression to RA in individual patients presenting with UA. This study investigates the accuracy of this prediction rule in independent cohorts of patients with UA. METHODS: In 3 cohorts of patients with recent-onset UA, from the UK, Germany, and The Netherlands, the prediction score and the corresponding chance of developing RA were calculated. These data were compared with the observed disease outcome after > or =1 year of followup. Positive predictive values (PPVs) and negative predictive values (NPVs) were calculated and the overall discriminative ability of the prediction rule was assessed using area under the receiver operating characteristic curves (AUCs). RESULTS: Since data on the severity of morning stiffness were not available in all validation cohorts, the prediction rule was rederived with the duration of morning stiffness as a substitute. The AUC for this rule was 0.88 (SEM 0.015). For each validation cohort, the AUC was 0.83 (SEM 0.041), 0.82 (SEM 0.037), and 0.95 (SEM 0.031) in the British, German, and Dutch cohorts, respectively. The NPV (for a prediction score < or =6) in these 3 cohorts was 83%, 83%, and 86%, respectively; the PPV (for a prediction score > or =8) was 100%, 93%, and 100%, respectively. CONCLUSION: The recently derived prediction rule, when applied to 3 independent cohorts of patients with UA, has an excellent discriminative ability for assessing the likelihood of progression to RA. Application of this rule will allow individualized treatment decision-making for patients with UA.

Parsonage G, Filer A, Bik M, Hardie D, Lax S, Howlett K, Church LD, Raza K, Wong SH, Trebilcock E, Scheel-Toellner D, Salmon M, Lord JM, Buckley CD. · Rheumatology Research Group, MRC Centre for Immune Regulation, Institute for Biomedical Research, University of Birmingham, Vincent Drive, Edgbaston, Birmingham B15 2TT, UK. · Arthritis Res Ther. · Pubmed #18433499 links to  free full text

Abstract: INTRODUCTION: A surprising feature of the inflammatory infiltrate in rheumatoid arthritis is the accumulation of neutrophils within synovial fluid and at the pannus cartilage boundary. Recent findings suggest that a distinct subset of IL-17-secreting T-helper cells (TH17 cells) plays a key role in connecting the adaptive and innate arms of the immune response and in regulating neutrophil homeostasis. We therefore tested the hypothesis that synovial fibroblasts bridge the biological responses that connect TH17 cells to neutrophils by producing neutrophil survival factors following their activation with IL-17. METHODS: IL-17-expressing cells in the rheumatoid synovium, and IL-17-expressing cells in the peripheral blood, and synovial fluid were examined by confocal microscopy and flow cytometry, respectively. Peripheral blood neutrophils were cocultured either with rheumatoid arthritis synovial fibroblasts (RASF) or with conditioned medium from RASF that had been pre-exposed to recombinant human IL-17, TNFalpha or a combination of the two cytokines. Neutrophils were harvested and stained with the vital mitochondrial dye 3,3'-dihexyloxacarbocyanine iodide before being enumerated by flow cytometry. RESULTS: TH17-expressing CD4+ cells were found to accumulate within rheumatoid synovial tissue and in rheumatoid arthritis synovial fluid. RASF treated with IL-17 and TNFalpha (RASFIL-17/TNF) effectively doubled the functional lifespan of neutrophils in coculture. This was entirely due to soluble factors secreted from the fibroblasts. Specific depletion of granulocyte-macrophage colony-stimulating factor from RASFIL-17/TNF-conditioned medium demonstrated that this cytokine accounted for approximately one-half of the neutrophil survival activity. Inhibition of phosphatidylinositol-3-kinase and NF-kappaB pathways showed a requirement for both signalling pathways in RASFIL-17/TNF-mediated neutrophil rescue. CONCLUSION: The increased number of neutrophils with an extended lifespan found in the rheumatoid synovial microenvironment is partly accounted for by IL-17 and TNFalpha activation of synovial fibroblasts. TH17-expressing T cells within the rheumatoid synovium are likely to contribute significantly to this effect.

Hardy R, Rabbitt EH, Filer A, Emery P, Hewison M, Stewart PM, Gittoes NJ, Buckley CD, Raza K, Cooper MS. · Division of Medical Sciences, University of Birmingham, Queen Elizabeth Hospital, Edgbaston, Birmingham, UK. · Ann Rheum Dis. · Pubmed #18420938 links to  free full text

Abstract: BACKGROUND: Isolated, primary synovial fibroblasts generate active glucocorticoids through expression of 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1). This enzyme produces cortisol from inactive cortisone (and prednisolone from prednisone). OBJECTIVE: To determine how intact synovial tissue metabolises glucocorticoids and to identify the local and systemic consequences of this activity by examination of glucocorticoid metabolism in patients with rheumatoid arthritis (RA). METHODS: Synovial tissue was taken from patients with RA during joint replacement surgery. Glucocorticoid metabolism in explants was assessed by thin-layer chromatography and specific enzyme inhibitors. RT-PCR and immunohistochemistry were used to determine expression and distribution of 11beta-HSD enzymes. Systemic glucocorticoid metabolism was examined in patients with RA using gas chromatography/mass spectrometry. RESULTS: Synovial tissue synthesised cortisol from cortisone, confirming functional 11beta-HSD1 expression. In patients with RA, enzyme activity correlated with donor erythrocyte sedimentation rate (ESR). Synovial tissues could also convert cortisol back to cortisone. Inhibitor studies and immunohistochemistry suggested this was owing to 11beta-HSD2 expression in synovial macrophages, whereas 11beta-HSD1 expression occurred primarily in fibroblasts. Synovial fluids exhibited lower cortisone levels than matched serum samples, indicating net local steroid activation. Urinary analyses indicated high 11beta-HSD1 activity in untreated patients with RA compared with controls and a significant correlation between total body 11beta-HSD1 activity and ESR. CONCLUSIONS: Synovial tissue metabolises glucocorticoids, the predominant effect being glucocorticoid activation, and this increases with inflammation. Endogenous glucocorticoid production in the joint is likely to have an impact on local inflammation and bone integrity.

Jobanputra P, Amarasena R, Maggs F, Homer D, Bowman S, Rankin E, Filer A, Raza K, Jubb R. · Department of Rheumatology, Selly Oak Hospital, University Hospital Birmingham NHS Foundation Trust, Raddlebarn Road, Birmingham, B29 6JD, UK. · BMC Musculoskelet Disord. · Pubmed #18405372 links to  free full text

Abstract: BACKGROUND: Spontaneous reporting systems for adverse drug reactions (ADRs) are handicapped by under-reporting and limited detail on individual cases. We report an investigation from a local surveillance for serious adverse drug reactions associated with disease modifying anti-rheumatic drugs that was triggered by the occurrence of liver failure in two of our patients. METHODS: Serious ADR reports have been solicited from local clinicians by regular postcards over the past seven years. Patients', who had hepatotoxicity on sulfasalazine and met a definition of a serious ADR, were identified. Two clinicians reviewed structured case reports and assessed causality by consensus and by using a causality assessment instrument. The likely frequency of hepatotoxicity with sulfasalazine was estimated by making a series of conservative assumptions. RESULTS: Ten cases were identified: eight occurred during surveillance. Eight patients were hospitalised, two in hepatic failure - one died after a liver transplant. All but one event occurred within 6 weeks of treatment. Seven patients had a skin rash, three eosinophilia and one interstitial nephritis. Five patients were of Black British of African or Caribbean descent. Liver enzymes showed a hepatocellular pattern in four cases and a mixed pattern in six. Drug-related hepatotoxicity was judged probable or highly probable in 8 patients. The likely frequency of serious hepatotoxicity with sulfasalazine was estimated at 0.4% of treated patients. CONCLUSION: Serious hepatotoxicity associated with sulfasalazine appears to be under-appreciated and intensive monitoring and vigilance in the first 6 weeks of treatment is especially important.

Chan A, Filer A, Parsonage G, Kollnberger S, Gundle R, Buckley CD, Bowness P. · Medical Research Council Human Immunology Unit, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Oxford, UK. · Arthritis Rheum. · Pubmed #18311795 links to  free full text

Abstract: OBJECTIVE: Fibroblast-like synoviocytes (FLS) are potentially directly involved in the propagation of inflammation. We have previously shown evidence of an expanded activated population of natural killer (NK) cells in spondylarthritis (SpA) patients. In the present study, we sought to determine whether the interaction between NK cells and FLS from SpA patients results in a proinflammatory response. METHODS: Autologous NK cells and FLS were obtained from 6 patients with SpA, 4 patients with rheumatoid arthritis (RA), and 8 patients with osteoarthritis (OA). Physical interactions between NK cells and FLS were studied by time-lapse phase-contrast microscopy. Fluorescence-activated cell sorting was used to study the activation, proliferation, and survival of NK cells in contact with FLS. Cytokine and stromal factor production were measured by a multiple cytokine bead assay. RESULTS: NK cells both adhered to and migrated beneath the FLS monolayer (pseudoemperipolesis). FLS from SpA and RA patients supported increased pseudoemperipolesis, activation, cytokine production, and survival of NK cells. The production of proinflammatory cytokines, including interleukin-6 (IL-6), IL-8, IL-1beta, and IL-15, was increased in cocultures of NK cells and FLS, particularly in those from RA and SpA patients. Production of interferon-gamma, RANTES, and matrix metalloproteinase 3 (MMP-3) by NK cell and FLS coculture was greatest in SpA patients. Surface expression of IL-15 on FLS was significantly increased in SpA and RA patients, but not OA patients. Blockade with an IL-15 monoclonal antibody resulted in increased apoptosis of NK cells. CONCLUSION: FLS promote the migration, activation, and survival of NK cells. The interaction of NK cells with FLS results in increased IL-15 expression by FLS and the production of proinflammatory chemokines, cytokines, and MMPs, which may contribute to joint inflammation. This response was much more marked in SpA and RA patients as compared with OA patients.

Filer A, Raza K, Salmon M, Buckley CD. · Rheumatology Research Group, MRC Center for Immune Regulation, Division of Immunity and Infection, University of Birmingham, Birmingham B15 2TT, United Kingdom. · Discov Med. · Pubmed #17343801 No free full text.

Abstract: Why chronic inflammatory reactions persist in specific sites, such as rheumatoid arthritis in the joints, remains a mystery. Current models of inflammation have concentrated upon the responses of lymphocytes such as B and T cells to specific antigens, and have attempted, often unsuccessfully, to address the causative agent. However recent studies have shown that stromal cells such as macrophages, endothelial cells, and fibroblasts play important roles in the switch that turns a spontaneously resolving acute inflammatory response within a tissue into chronic and persistent disease. Therapeutic manipulation of the stromal microenvironment has been particularly effective in treating cancer and is likely to provide novel therapies to achieve improved control of chronic inflammatory disease.

Hardy RS, Filer A, Cooper MS, Parsonage G, Raza K, Hardie DL, Rabbitt EH, Stewart PM, Buckley CD, Hewison M. · Division of Medical Sciences, Institute of Biomedical Research, The University of Birmingham Medical School, Birmingham, UK. · Arthritis Res Ther. · Pubmed #16846535 links to  free full text

Abstract: Stromal cells such as fibroblasts play an important role in defining tissue-specific responses during the resolution of inflammation. We hypothesized that this involves tissue-specific regulation of glucocorticoids, mediated via differential regulation of the enzyme 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1). Expression, activity and function of 11beta-HSD1 was assessed in matched fibroblasts derived from various tissues (synovium, bone marrow and skin) obtained from patients with rheumatoid arthritis or osteoarthritis. 11beta-HSD1 was expressed in fibroblasts from all tissues but mRNA levels and enzyme activity were higher in synovial fibroblasts (2-fold and 13-fold higher mRNA levels in dermal and synovial fibroblasts, respectively, relative to bone marrow). Expression and activity of the enzyme increased in all fibroblasts following treatment with tumour necrosis factor-alpha or IL-1beta (bone marrow: 8-fold and 37-fold, respectively, compared to vehicle; dermal fibroblasts: 4-fold and 14-fold; synovial fibroblasts: 7-fold and 31-fold; all P < 0.01 compared with vehicle). Treatment with IL-4 or interferon-gamma was without effect, and there was no difference in 11beta-HSD1 expression between fibroblasts (from any site) obtained from patients with rheumatoid arthritis or osteoarthritis. In the presence of 100 nmol/l cortisone, IL-6 production--a characteristic feature of synovial derived fibroblasts--was significantly reduced in synovial but not dermal or bone marrow fibroblasts. This was prevented by co-treatment with an 11beta-HSD inhibitor, emphasizing the potential for autocrine activation of glucocorticoids in synovial fibroblasts. These data indicate that differences in fibroblast-derived glucocorticoid production (via the enzyme 11beta-HSD1) between cells from distinct anatomical locations may play a key role in the predeliction of certain tissues to develop persistent inflammation.

Filer A, Parsonage G, Smith E, Osborne C, Thomas AM, Curnow SJ, Rainger GE, Raza K, Nash GB, Lord J, Salmon M, Buckley CD. · MRC Centre for Immune Regulation, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK. · Arthritis Rheum. · Pubmed #16802344 links to  free full text

Abstract: OBJECTIVE: Synovial fibroblasts share a number of phenotype markers with fibroblasts derived from bone marrow. In this study we investigated the role of matched fibroblasts obtained from 3 different sources (bone marrow, synovium, and skin) to test the hypothesis that synovial fibroblasts share similarities with bone marrow-derived fibroblasts in terms of their ability to support survival of T cells and neutrophils. METHODS: Matched synovial, bone marrow, and skin fibroblasts were established from 8 different patients with rheumatoid arthritis who were undergoing knee or hip surgery. Resting or activated fibroblasts were cocultured with either CD4 T cells or neutrophils, and the degree of leukocyte survival, apoptosis, and proliferation were measured. RESULTS: Fibroblasts derived from all 3 sites supported increased survival of CD4 T cells, mediated principally by interferon-beta. However, synovial and bone marrow fibroblasts shared an enhanced site-specific ability to maintain CD4 T cell survival in the absence of proliferation, an effect that was independent of fibroblast activation or proliferation but required direct T cell-fibroblast cell contact. In contrast, fibroblast-mediated neutrophil survival was less efficient, being independent of the site of origin of the fibroblast but dependent on prior fibroblast activation, and mediated solely by soluble factors, principally granulocyte-macrophage colony-stimulating factor. CONCLUSION: These results suggest an important functional role for fibroblasts in the differential accumulation of leukocyte subsets in a variety of tissue microenvironments. The findings also provide a potential explanation for site-specific differences in the pattern of T cell and neutrophil accumulation observed in chronic inflammatory diseases.

Lally F, Smith E, Filer A, Stone MA, Shaw JS, Nash GB, Buckley CD, Rainger GE. · Department of Physiology, Medical School, The University of Birmingham, Edgbaston, Birmingham B15 2TT, UK. · Arthritis Rheum. · Pubmed #16255036 links to  free full text

Abstract: OBJECTIVE: Rheumatoid arthritis (RA) is classically thought of as a Th1, T lymphocyte-driven disease of the adaptive immune system. However, cells of the innate immune system, including neutrophils, are prevalent within the diseased joint, and accumulate in large numbers. This study was undertaken to determine whether cells of the rheumatoid stromal microenvironment could establish an inflammatory environment in which endothelial cells are conditioned in a disease-specific manner to support neutrophil recruitment. METHODS: Human umbilical vein endothelial cells (ECs) and fibroblasts isolated from the synovium or skin of RA patients were established in coculture on opposite sides of porous transwell filters. After 24 hours of EC conditioning, the membranes were incorporated into a parallel-plate, flow-based adhesion assay and levels of neutrophil adhesion to ECs were measured. RESULTS: ECs cocultured with synovial, but not skin, fibroblasts could recruit neutrophils in a manner that was dependent on the number of fibroblasts. Antibody blockade of P-selectin or E-selectin reduced neutrophil adhesion, and an antibody against CD18 (the beta2 integrin) abolished adhesion. Blockade of CXCR2, but not CXCR1, also greatly inhibited neutrophil recruitment. Interleukin-6 (IL-6) was detectable in coculture supernatants, and both IL-6 and neutrophil adhesion were reduced in a dose-dependent manner by hydrocortisone added to cocultures. Antibody blockade of IL-6 also effectively abolished neutrophil adhesion. CONCLUSION: Synovial fibroblasts from the rheumatoid joint play an important role in regulating the recruitment of inflammatory leukocytes during active disease. This process may depend on a previously unsuspected route of IL-6-mediated crosstalk between fibroblasts and endothelial cells.

Scaife S, Brown R, Kellie S, Filer A, Martin S, Thomas AM, Bradfield PF, Amft N, Salmon M, Buckley CD. · Yamanouchi Research Institute, Oxford, UK. · Rheumatology (Oxford). · Pubmed #15292528 links to  free full text

Abstract: OBJECTIVE: To identify differentially expressed genes in synovial fibroblasts and examine the effect on gene expression of exposure to TNF-alpha and IL-1beta. METHODS: Restriction fragment differential display was used to isolate genes using degenerate primers complementary to the lysophosphatidic acid acyl transferase gene family. Differential gene expression was confirmed by reverse transcription-polymerase chain reaction and immunohistochemistry using a variety of synovial fibroblasts, including cells from patients with osteoarthritis and self-limiting parvovirus arthritis. RESULTS: Irrespective of disease process, synovial fibroblasts constitutively produced higher levels of IL-6 and monocyte chemoattractant protein 1 (MCP-1) (CCL2) than skin fibroblasts. Seven genes were differentially expressed in synovial fibroblasts compared with skin fibroblasts. Of these genes, four [tissue factor pathway inhibitor 2 (TFPI2), growth regulatory oncogene beta (GRObeta), manganese superoxide dismutase (MnSOD) and granulocyte chemotactic protein 2 (GCP-2)] were all found to be constitutively overexpressed in synoviocytes derived from patients with osteoarthritis. These four genes were only weakly expressed in other synovial fibroblasts (rheumatoid and self-limiting parvovirus infection). However, expression in all types of fibroblasts was increased after stimulation with TNF-alpha and IL-1beta. Three other genes (aggrecan, biglycan and caldesmon) were expressed at higher levels in all types of synovial fibroblasts compared with skin fibroblasts even after stimulation with TNF-alpha and IL-1. CONCLUSIONS: Seven genes have been identified with differential expression patterns in terms of disease process (osteoarthritis vs rheumatoid arthritis), state of activation (resting vs cytokine activation) and anatomical location (synovium vs skin). Four of these genes, TFPI2, GRObeta (CXCL2), MnSOD and GCP-2 (CXCL6), were selectively overexpressed in osteoarthritis fibroblasts rather than rheumatoid fibroblasts. While these differences may represent differential behaviour of synovial fibroblasts in in vitro culture, these observations suggest that TFPI2, GRObeta (CXCL2), MnSOD and GCP-2 (CXCL6) may represent new targets for treatments specifically tailored to osteoarthritis.

Parsonage G, Falciani F, Burman A, Filer A, Ross E, Bofill M, Martin S, Salmon M, Buckley CD. · MRC Centre for Immune Regulation, Division of Immunity and Infection, Birmingham University, Birmingham, UK. · Thromb Haemost. · Pubmed #14515190 No free full text.

Abstract: We investigated the extent to which fibroblasts isolated from diverse tissues differ in their capacity to modulate inflammation by comparing the global gene expression profiles of cultured human fibroblasts from skin, acute and chronically inflamed synovium, lymph node and tonsil. The responses of these fibroblasts to TNF-alpha, IFN-gamma and IL-4 stimulation were markedly different, as revealed by hierarchical cluster analysis and principal component analysis. In the absence of exogenous cytokine, synovial and skin fibroblasts exhibited similar patterns of gene expression. However their transcriptional profiles diverged upon treatment with TNF-alpha. This proved to be biologically relevant, as TNF-alpha induced the secretion of different patterns and amounts of IL-6, IL-8 and CCL2 (MCP-1) in the two fibroblast types. Co-culture of skin or synovial fibroblasts with synovial fluid-derived mononuclear cells provided further evidence that these transcriptional differences were functionally significant in an ex vivo setting. Interestingly, the transcriptional response of skin fibroblasts to IL-4 converged with that of TNF-alpha-treated synovial fibroblasts, suggesting resident tissue fibroblasts and their blood-borne precursors may be imprinted by inflammatory cytokines that are characteristic of different tissues. Our data supports the concept that fibroblasts are heterogeneous, and that they contribute to the tissue-specificity of inflammatory reactions. Fibroblasts are therefore likely to play an active role in the persistence of chronic inflammatory reactions.

Yee CS, Filer A, Pace A, Douglas K, Situnayake D, Rowe IF, Anonymous00305. · Dudley Guest Hospital, UK. · Rheumatology (Oxford). · Pubmed #12730544 links to  free full text

Abstract: OBJECTIVES: There are currently two anti-tumour necrosis factor (anti-TNF) therapies licensed for treatment of rheumatoid arthritis (RA). A British Society for Rheumatology (BSR) working party defined criteria for patients that would be suitable for such treatment. The aim of this study was to determine the prevalence of these patients attending rheumatology out-patient departments across the West Midlands. METHODS: Data were collected over a 2-week period in adult out-patient departments of 12 centres. A questionnaire was completed at each patient review. Disease activity scores (DAS-28) were recorded for those who had failed methotrexate treatment and at least one other disease-modifying anti-rheumatic drug (DMARD) in the absence of contraindications to anti-TNF therapy. Information was also collected on the number of DMARDs failed and the use of steroid therapy. RESULTS: A total of 1441 patients with RA were assessed; 177 (12.3%) patients had failed methotrexate and at least one other DMARD. Of these, 19 had contraindications to the use of anti-TNF therapy. In the remaining 158 patients (11%), 80 (5.6%) had a DAS-28 score of >5.1, thus fulfilling BSR criteria for use of anti-TNF therapy. Those with a DAS-28 score of < or = 5.1 were significantly more likely to have been taking steroids compared with those with a DAS-28 score >5.1 (68.2 and 49.3%, respectively, P=0.024). CONCLUSIONS: Of patients with RA attending adult rheumatology out-patient clinics in the West Midlands, 5.6% would meet BSR criteria for use of anti-TNF therapy. Eligibility may be affected by steroid use.