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ID PMID Title PublicationDate abstract
21962830 Treatment of TNF mediated diseases by selective inhibition of soluble TNF or TNFR1. 2011 Oct The TNF signaling pathway is a valuable target in the therapy of autoimmune diseases, and anti-TNF drugs are successfully used to treat diseases such as rheumatoid arthritis, Crohn's disease and psoriasis. By their ability to interfere with inflammatory processes at multiple levels, these TNF blockers have become invaluable tools to inhibit the inflammation induced damage and allow recovery of the affected tissues. Unfortunately this therapy has some drawbacks, including increased risk of infection and malignancy, and remarkably, the onset of new auto-immune diseases. Some of these effects are caused by the unwanted abrogation of beneficial TNF signaling. More specific targeting of the pathological TNF-induced signaling might lead to broader applicability and improved safety. Specificity might be increased by inhibiting the soluble TNF/TNFR1 axis while leaving the often beneficial transmembrane TNF/TNFR2 signaling untouched. This approach looks promising because it inhibits the pathological effects of TNF and reduces the side effects, and it opens the way for the treatment of other diseases in which TNFR2 inhibition is detrimental. In this review we give an overview of in vivo mouse studies of TNF mediated pathologies demonstrating that the blockade or genetic deletion of sTNF or TNFR1 is preferable over total TNF blockade.
23282142 Discovery of a new class of inhibitors for the protein arginine deiminase type 4 (PAD4) by 2012 BACKGROUND: Rheumatoid arthritis (RA) is an autoimmune disease with unknown etiology. Anticitrullinated protein autoantibody has been documented as a highly specific autoantibody associated with RA. Protein arginine deiminase type 4 (PAD4) is the enzyme responsible for catalyzing the conversion of peptidylarginine into peptidylcitrulline. PAD4 is a new therapeutic target for RA treatment. In order to search for inhibitors of PAD4, structure-based virtual screening was performed using LIDAEUS (Ligand discovery at Edinburgh university). Potential inhibitors were screened experimentally by inhibition assays. RESULTS: Twenty two of the top-ranked water-soluble compounds were selected for inhibitory screening against PAD4. Three compounds showed significant inhibition of PAD4 and their IC50 values were investigated. The structures of the three compounds show no resemblance with previously discovered PAD4 inhibitors, nor with existing drugs for RA treatment. CONCLUSION: Three compounds were discovered as potential inhibitors of PAD4 by virtual screening. The compounds are commercially available and can be used as scaffolds to design more potent inhibitors against PAD4.
22573549 Involvement of 15-lipoxygenase in the inflammatory arthritis. 2012 Jul 15-Lipoxygenase (15-LOX) is involved in many pathological processes. The aim of this study is to examine the role of 15-LOX in the matrix metalloproteinase (MMP) expression and inflammatory arthritis. It was found that treatment of 15-LOX downstream product of 15-(S)-HETE (15-S-hydroxyeicosatetraenoic acid) increased the mRNA and protein levels of MMP-2 in rheumatoid arthritis synovial fibroblast (RASF) derived from rheumatoid arthritis patients. The enhancement effect of 15-(S)-HETE was antagonized by the addition of LY294002 (PI3K inhibitor) and PDTC (NF-κB inhibitor). Treatment of 15-(S)-HETE increased the phosphorylation of AKT, nuclear translocation of p65 and the breakdown of IκBα. TNF-α and IL-1β are the key cytokines involved in arthritis and also increase the activity of MMP-2 in RASF, which was antagonized by pretreatment with 15-LOX inhibitor PD146176 or knockdown of 15-LOX. It was also found that these two cytokines increased the expression of 15-LOX in RASF. Treatment of glucocorticoid but not NSAIDs inhibited 15-(S)-HETE-induced expression of MMP-2. In comparison with wild-type mice, adjuvant-induced arthritis and MMP-2 expression in synovial membrane were markedly inhibited in 15-LOX knockout (KO) mice. These results indicate that 15-LOX plays an important role in the disease progression of arthritis and may be involved in the inflammatory action induced by TNF-α and IL-1β. 15-LOX is thus a good target for developing drugs in the treatment of inflammatory arthritis.
21706128 Individual interviews and focus groups in patients with rheumatoid arthritis: a comparison 2012 Mar PURPOSE: To compare two different approaches to performing focus groups and individual interviews, an open approach, and an approach based on the International Classification of Functioning, Disability and Health (ICF). METHODS: Patients with rheumatoid arthritis attended focus groups (n = 49) and individual interviews (n = 21). Time, number of concepts, ICF categories identified, and sample size for reaching saturation of data were compared. Descriptive statistics, Chi-square tests, and independent t tests were performed. RESULTS: With an overall time of 183 h, focus groups were more time consuming than individual interviews (t = 9.782; P < 0.001). In the open approach, 188 categories in the focus groups and 102 categories in the interviews were identified compared to the 231 and 110 respective categories identified in the ICF-based approach. Saturation of data was reached after performing five focus groups and nine individual interviews in the open approach and five focus groups and 12 individual interviews in the ICF-based approach. CONCLUSION: The method chosen should depend on the objective of the study, issues related to the health condition, and the study's participants. We recommend performing focus groups if the objective of the study is to comprehensively explore the patient perspective.
22661646 Intravenous golimumab is effective in patients with active rheumatoid arthritis despite me 2013 Mar OBJECTIVES: Evaluate the efficacy of intravenous golimumab 2 mg/kg+methotrexate (MTX) in patients with active rheumatoid arthritis (RA) receiving MTX. METHODS: Patients (n=592) with active disease (≥6/66 swollen, ≥6/68 tender joints, C-reactive protein ≥1.0 mg/dl, rheumatoid factor positive and/or anticyclic citrullinated protein antibody positive at screening) despite MTX (15-25 mg/week) participated in this double-blind, placebo-controlled, phase 3 study. Patients were randomised (2:1) to receive intravenous golimumab 2 mg/kg, or placebo infusions at weeks 0 and 4 and every (q) 8 weeks; patients continued MTX. Placebo patients with <10% improvement in combined swollen/tender joint counts at week 16 could early escape to intravenous golimumab 2 mg/kg. The primary endpoint was week 14 American College of Rheumatology 20% (ACR20) response. Analyses employed non-responder imputation and last-observation-carried-forward. RESULTS: At week 14, significantly (p<0.001) larger proportions of golimumab+MTX than placebo+MTX patients achieved ACR20 response (59% vs 25%, respectively), a disease activity score of good/moderate (EULAR) response (81% vs 40%), and greater median improvement in health assessment questionnaire scores (0.500 vs 0.125). Improvements versus placebo+MTX were observed by week 2. Similar proportions of patients receiving golimumab+MTX and placebo+MTX, respectively, reported adverse events through week 16 (47% and 44%) and week 24 (53% and 49%). Serious adverse events were reported by more golimumab+MTX (4.1%) than placebo+MTX (2%) patients at week 24. CONCLUSION: The addition of intravenous golimumab rapidly and significantly improved signs and symptoms in patients with active RA despite ongoing MTX, in some patients by week 2.
20505937 Anti-cyclic citrullinated peptide and rheumatoid factor in HIV positive patients. 2011 Dec The aim of this study was to determine the difference of anti-CCP and RF between HIV positive patients and a healthy control group. The rheumatological complications in HIV positive patients are rather common and are recognized as a serious problem that requires more attention. Anti-CCP and RF are the only laboratory tools for rheumatoid disorder diagnostics and predictors of the course of the disease. We determined anti-CCP and RF in sera of 35 healthy volunteers and 45 HIV positive patients. Data were compared using chi-square test, Mann-Whitney test and ROC curve statistics. Both parameters were significantly higher in HIV positive patients, and significant differences between areas under the anti-CCP and RF curves were observed. Median value for anti-CCP in HIV positive patients was higher than the reference interval, and RF values were, in the reference interval, suggested by the manufacturer. Both anti-CCP and RF are significantly higher in HIV positive patients. ROC analysis showed that anti-CCP distinguishes the two groups better than RF. Because of that, it would be of a great interest to investigate the HIV positive patients after the detailed rheumatological examination.
22123179 CX(3)CR1 drives cytotoxic CD4(+)CD28(-) T cells into the brain of multiple sclerosis patie 2012 Feb Immunosenescence, or ageing of the immune system, contributes to the increased morbidity and mortality seen in the elderly population. Premature immunosenescence is shown to occur in a subgroup of patients with autoimmune diseases. One of the main characteristics of immunosenescence is the expansion of CD4(+)CD28(-) T cells in the blood. In this study, we investigate the potential contribution of these cells to disease processes in a subgroup of multiple sclerosis (MS) and rheumatoid arthritis (RA) patients. Characterization of CD4(+)CD28(-) T cells in patients and healthy controls reveals that they have an inflammation-seeking effector-memory T cell phenotype with cytotoxic properties, as they expel cytotoxic granules in response to a polyclonal stimulus or MS-related autoantigens. We identify CX(3)CR1, the fractalkine receptor, as a selective marker to discriminate CD4(+)CD28(-) T cells from their CD4(+)CD28(+) counterparts. CX(3)CR1 expression enables CD4(+)CD28(-) T cells to migrate towards a fractalkine gradient in vitro. In addition, we find increased levels of fractalkine in the cerebrospinal fluid and inflammatory lesions of MS patients. We demonstrate for the first time that CD4(+)CD28(-) T cells accumulate in MS lesions of a subgroup of patients. Moreover, we have indications that these cells are cytotoxic in the target tissue. Overall, our findings suggest that CD4(+)CD28(-) T cells migrate in response to a chemotactic gradient of fractalkine to sites of inflammation, where they contribute to the inflammatory processes in a subgroup of patients with MS and RA.
21859701 Are head-to-head trials of biologics needed? The role of value of information methods in a 2011 Sep Reimbursement decisions are typically based on cost-effectiveness analyses. While a cost-effectiveness analysis can identify the optimum strategy, there is usually some degree of uncertainty around this decision. Sources of uncertainty include statistical sampling error in treatment efficacy measures, underlying baseline risk, utility measures and costs, as well as uncertainty in the structure of the model. The optimal strategy is therefore only optimal on average, and a decision to adopt this strategy might still be the wrong decision if all uncertainty could be eliminated. This means that there is a quantifiable expected (average) loss attaching to decisions made under uncertainty, and hence a value in collecting information to reduce that uncertainty. Value of information (VOI) analyses can be used to provide guidance on whether more research would be cost-effective, which particular model inputs (parameters) have the most bearing on decision uncertainty, and can also help with the design and sample size of further research. Here, we introduce the key concepts in VOI analyses, and highlight the inputs required to calculate it. The adoption of the new biologic treatments for RA and PsA tends to be based on placebo-controlled trials. We discuss the possible role of VOI analyses in deciding whether head-to-head comparisons of the biologic therapies should be carried out, illustrating with examples from other fields. We emphasize the need for a model of the natural history of RA and PsA, which reflects a consensus view.
21926327 Resistance to regulatory T cell-mediated suppression in rheumatoid arthritis can be bypass 2011 Oct 4 Increasing evidence suggests that regulatory T cell (Treg) function is impaired in chronic inflammatory diseases such as rheumatoid arthritis (RA). Here we demonstrate that Tregs are unable to modulate the spontaneous production of TNF-α from RA synovial cells cultured from the diseased synovium site. Cytokine (IL-2, IL-6, TNF-α) activated T cells (Tck), cells we previously demonstrated to mimic the effector function of pathogenic RA synovial T cells, contained Tregs that survived and divided in this cytokine environment; however, the up-regulation of key molecules associated with Treg function (CTLA-4 and LFA-1) was impaired. Furthermore, Tregs were unable to suppress the function of Tcks, including contact-dependent induction of TNF-α from macrophages, supporting the concept that impaired Treg function/responsiveness contributes to chronicity of RA. However, ectopic foxp3 expression in both Tcks and pathogenic RA synovial T cells attenuated their cytokine production and function, including contact-dependent activation of macrophages. This diminished response to cytokine activation after ectopic foxp3 expression involved inhibited NF-κB activity and differed mechanistically from that displayed endogenously in conventional Tregs. These results suggest that diseases such as RA may perpetuate owing to the inability of Tregs to control cytokine-activated T-cell function. Understanding the mechanism whereby foxp3 attenuates the pathogenic function of synovial T cells may provide insight into the mechanisms of chronicity in inflammatory disease and potentially reveal new therapeutic candidates.
22995227 New paradigm for patient-reported outcomes assessment in foot & ankle research: computeriz 2012 Aug BACKGROUND: Accurately measuring, reporting and comparing outcomes is essential for improving health care delivery. Current challenges with available health status scales include patient fatigue, floor/ceiling effects and validity/reliability. METHODS: This study compared Patient Reported Outcomes Measurement Information System (PROMIS)-based Lower Extremity Physical Function Computerized Adaptive Test (LE CAT) and two legacy scales -the Foot and Function Index (FFI) and the sport module from the Foot and Ankle Ability Measure (spFAAM) -for 287 patients scheduled for elective foot and ankle surgery. We documented the time required by patients to complete the instrument, instrument precision, and the extent to which each instrument covered the full range of physical functioning across the patient sample. RESULTS: Average time of test administration: 66 seconds for LE CAT, 130 seconds for spFAAM and 239 seconds for FFI. All three instruments were fairly precise at intermediate physical functioning levels (i.e., Standard Error of Measurement < 0.35), were relatively less precise at the higher trait levels and the LE CAT maintained precision in the lower range while the spFAAM and FFI's had decreased precision. The LE CAT had less floor/ceiling effects than the FFI and the spFAAM. CONCLUSION: The LE CAT showed considerable advantage compared to legacy scales for measuring patient-reported outcomes in orthopaedic patients with foot and ankle problems. CLINICAL RELEVANCE: A paradigm shift to broader use of PROMIS-based CATs should be considered to improve precision and reduce patient burden with patient-reported outcome measuremen foot and ankle patients.
22970175 A knowledge-based method for association studies on complex diseases. 2012 Complex disorders are a class of diseases whose phenotypic variance is caused by the interplay of multiple genetic and environmental factors. Analyzing the complexity underlying the genetic architecture of such traits may help develop more efficient diagnostic tests and therapeutic protocols. Despite the continuous advances in revealing the genetic basis of many of complex diseases using genome-wide association studies (GWAS), a major proportion of their genetic variance has remained unexplained, in part because GWAS are unable to reliably detect small individual risk contributions and to capture the underlying genetic heterogeneity. In this paper we describe a hypothesis-based method to analyze the association between multiple genetic factors and a complex phenotype. Starting from sets of markers selected based on preexisting biomedical knowledge, our method generates multi-marker models relevant to the biological process underlying a complex trait for which genotype data is available. We tested the applicability of our method using the WTCCC case-control dataset. Analyzing a number of biological pathways, the method was able to identify several immune system related multi-SNP models significantly associated with Rheumatoid Arthritis (RA) and Crohn's disease (CD). RA-associated multi-SNP models were also replicated in an independent case-control dataset. The method we present provides a framework for capturing joint contributions of genetic factors to complex traits. In contrast to hypothesis-free approaches, its results can be given a direct biological interpretation. The replicated multi-SNP models generated by our analysis may serve as a predictor to estimate the risk of RA development in individuals of Caucasian ancestry.
23040353 Oral manifestations of systemic autoimmune and inflammatory diseases: diagnosis and clinic 2012 Sep CONTEXT: Systemic autoimmune and inflammatory diseases often manifest oral lesions in their earliest stages, and early diagnosis, which may be spurred by a dental examination, is key for improved outcomes. After systemic diagnosis, oral lesions benefit from specialized care by dentists in collaboration with the medical team. This review aims to educate dental clinicians about the most relevant systemic autoimmune and inflammatory conditions with accompanying oral lesions, their implications for health, and management strategies supported by the biomedical literature and clinical experience. Ulcerative conditions including Behcet and Crohn diseases are discussed, along with rheumatic conditions including Sjögren syndrome, lupus erythematosus, and rheumatoid arthritis. EVIDENCE ACQUISITION: Evidence was accumulated through PubMed searches using pertinent keywords for each subsection. References were reviewed and original publications examined to verify the accuracy of the information. We focused on evidence included in current reviews and randomized trials. Recommendations were supported by multiple studies and consensus expert opinion. EVIDENCE SYNTHESIS: Disease phenotypes described and clinical recommendations were synthesized from best-quality evidence available for each disease. Efforts were made to describe evidence selection within each disease section. CONCLUSIONS: Dentists play an important role in the early detection and multidisciplinary medical management of complex autoimmune diseases. It is important to recognize prevalent medical and dental issues and special needs of patients with autoimmune conditions. The management of many inflammatory conditions is similar, and often begins with the use of topical steroids, analgesics, and antimicrobial treatments, in addition to careful attention to oral hygiene and appropriate fluoride usage. In this brief review, we aim to discuss the presentation/prevalence, diagnosis, and treatment of oral manifestations encountered in autoimmune, autoinflammatory and systemic chronic inflammatory diseases. Systemic autoimmune conditions are estimated to affect 5% to 8% of Americans.(1) Oral manifestations are encountered with high frequency, and are often the first clinical signs or symptoms of the general disease. Optimal management of complex autoimmune diseases requires a multidisciplinary medical team including dentists to care for lesions of the oral cavity. The dental practitioner may be asked to play a primary role in the diagnosis of such conditions and to participate with other health professionals working together to achieve effective clinical management. To aid in this process, we discuss in this article the current general knowledge of systemic autoimmune conditions that present with prevalent oral manifestations. The focus is on the diagnosis and management of the oral component of each disease. Importantly, whereas the etiology and pathogenesis and systemic clinical presentation may vary, presentation in the oral cavity is often similar and many conditions involve oral ulcerations. For this reason, we discuss the differential diagnosis and management of the most common oral ulcerations in a general section and subsequently address individual conditions that present with oral ulcerations. Similarly, treatment of various autoimmune/inflammatory oral conditions is often common and involves modulation or suppression of the immune response locally and/or systemically and will be therefore addressed in a common section as well as individually for each disease when unique treatment regimens are recommended. We present here our general treatment recommendations based on clinical experience and literature review; however, it is critical that good clinical judgment and specifics of an individual case should determine the appropriate dental/oral medicine intervention for a specific patient.
21861867 Are we ready for therapeutic drug monitoring of biologic therapeutics? 2011 Aug 2 In the previous issue of Arthritis Research & Therapy, Ducourau and colleagues report that they retrospectively detected anti-infliximab antibodies in 21% of patients with rheumatic diseases. Patients with anti-infliximab antibodies had lower serum drug concentrations. These findings contribute to the existing evidence of immunogenicity of biologicals and its clinical relevance. We argue for therapeutic drug monitoring to optimize treatment response.
22390698 Interleukin-7: a key mediator in T cell-driven autoimmunity, inflammation, and tissue dest 2012 IL-7, expressed by stromal cells in primary lymphoid organs, is known for its critical role in the development and homeostatic expansion of T cells in humans and mice. IL-7 is equally important for B cell development in human and mice, but only in mice seems critical for B cell development and expansion. Recent studies demonstrate that this potent immunostimulatory cytokine is overexpressed in inflamed tissues of patients with (rheumatic) autoimmune diseases and that expression levels correlate with clinical parameters of disease. In inflamed tissues several cell types, including macrophages, dendritic cells, and fibroblasts produce IL-7. IL-7 primarily acts on T cells that abundantly express the IL-7 receptor and that are increased at the inflammatory sites, and predominantly induces Th1 and Th17-associated cytokine secretion. IL-7-mediated T cell-dependent activation of macrophages, dendritic cells and B cells is accompanied by up regulation of T cell differentiating factors, chemokines, adhesion/co-stimulatory molecules and catabolic cytokines and enzymes. Moreover, overexpression of IL-7 is associated with ectopic lymphoid aggregate formation, corresponding with the capacity of IL-7 to induce LTβ and TNFα and to activate innate lymphoid tissue inducer cells. Additionally, IL-7 promotes T cell-driven osteoclastogenesis and fibroblast activation, processes involved in tissue destruction in chronic inflammation. Altogether this suggests that IL-7 is an important proinflammatory mediator in several chronic (rheumatic) inflammatory autoimmune diseases. The substantial amelioration of inflammation and immunopathology in experimental animal models for these diseases by blocking IL-7(receptor) supports this role of IL-7 and demonstrates that IL-7 and its receptor represent novel targets for immunotherapy.
22730375 Angiopoietin-2 promotes inflammatory activation of human macrophages and is essential for 2012 Aug BACKGROUND: Angiopoietin (Ang)-1 and Ang-2, and their shared receptor Tie2, are expressed in rheumatoid arthritis (RA) synovial tissue, but the cellular targets of Ang signalling and the relative contributions of Ang-1 and Ang-2 to arthritis are poorly understood. OBJECTIVES: To determine the cellular targets of Ang signalling in RA synovial tissue, and the effects of Ang-2 neutralisation in murine collagen-induced arthritis (CIA). METHODS: RA and psoriatic arthritis (PsA) synovial biopsies were examined for expression of Tie2 and activated phospho (p)-Tie2 by quantitative immunohistochemistry and immunofluorescent double staining. Human monocyte and macrophage Tie2 expression was determined by flow cytometry and quantitative PCR. Regulation of macrophage intracellular signalling pathways and gene expression were examined by immunoblotting and ELISA. CIA was assessed in mice treated with saline, control antibody, prednisolone or neutralising anti-Ang-2 antibody. RESULTS: Expression of synovial Tie2 and p-Tie2 was similar in RA and PsA. Tie2 activation in RA patient synovial tissue was predominantly localised in synovial macrophages and was expressed by human macrophage. Ang-1 and Ang-2 stimulated activation of multiple intracellular signalling pathways, and cooperated with tumour necrosis factor to induce macrophage interleukin 6 and macrophage inflammatory protein 1α production. Ang-2 selectively suppressed macrophage thrombospondin-2 production. Ang-2 neutralisation significantly decreased disease severity, synovial inflammation, neo-vascularisation and joint destruction in established CIA. CONCLUSIONS: The authors identify synovial macrophages as primary targets of Ang signalling in RA, and demonstrate that Ang-2 promotes the pro-inflammatory activation of human macrophages. Ang-2 makes requisite contributions to pathology in CIA, indicating that targeting Ang-2 may be of therapeutic benefit in the treatment of RA.
22516983 [A multicenter study of coronary artery disease and its risk factors in rheumatoid arthrit 2012 Apr 18 OBJECTIVE: To learn about the prevalence and risk factors of coronary artery disease (CAD) in rheumatoid arthritis (RA). METHODS: Data were obtained from a 12-month retrospective investigation of the patients with RA, randomly selected from Departments of Rheumatology and Immunology in 21 big hospitals in China. The data were collected about their social conditions, clinical conditions, medications associated with RA, such as disease modifying anti-rheumatic drugs (DMARDs), non steroidal anti-inflammatory drugs (NSAIDs), glucocorticoid, biologic agents. A nonparameter test and multivariate logistic regression analysis were performed. RESULTS: In the study, 960 patients were enrolled. The prevalence of CAD was 3.5% in China, which was obviously higher than that of normal people. The prevalence of overweight and obesity, smoking, hypertension, diabetes mellitus, hypercholesterolemia and cerebrovascular disease were 35.1%, 12.3%, 17.0%, 7.7%, 0.4% and 3.0%, respectively. Compared with the control group, the CAD group had higher age [(64.7±9.3) years vs. (52.3±14.0) years,P<0.001], more rheumatoid nodules (14.7% vs. 3.1%,P=0.005), lower rate of hydroxychloroquine (HCQ) use (5.9% vs. 22.6%,P=0.021), higher prevalence rates of lung interstitial disease (17.5% vs. 7.0%,P<0.001), diabetes mellitus and hypertension (29.4% vs. 7.0%,P<0.001; 38.2% vs. 16.2%,P=0.001). There was no obvious correlation of CAD in RA with joint deformity, rheumatoid factor (RF) titer, glucocorticoid use, hypercholesterolemia and body mass index (BMI). Multivariate analysis showed higher age, diabetes mellitus and hypertension were independent predictors of CAD, and the use of HCQ was a protective factor of CAD. CONCLUSION: The prevalence of CAD is 3.5%. Higher age, diabetes mellitus and hypertension are independent predictors of CAD, and the use of HCQ is a protective factor of CAD.
21474483 A novel Saa3-promoter reporter distinguishes inflammatory subtypes in experimental arthrit 2011 Jul OBJECTIVE: To evaluate the applicability of a lentiviral (LV) serum amyloid A3 (Saa3)-promoter luciferase (Luc) reporter for assessing inflammation in experimental arthritis, synovial fibroblasts (SF) from osteoarthritis (OA) and rheumatoid arthritis (RA) patients. METHODS: In mice, synovium was transduced in vivo by cholesterol optimised LV, and two flares of acute joint inflammation were induced by injection of streptococcal cell wall (SCW) material into the knee-joint cavity. The time course of synovial inflammation was assessed using ex vivo luciferase assays, and histology. Uptake of (99m)technetium (Tc) was used to assess oedema. SF (n=12) of RA and OA patients were stratified by hierarchical clustering of whole genome expression profiles. Relative Saa3-promoter responses were determined in cytokine- or toll-like receptor (TLR)-stimulated SF subgroups. RESULTS: In vivo, the Saa3-promoter reporter activity was strongly upregulated at 1 and 2 days after the first and second SCW challenge. The Saa3-promoter activities during acute inflammation correlated with Tc uptake measurements but were more sensitive and able to respond to the ongoing synovitis in the chronic phase of SCW arthritis. Molecular stratification defined two inflammatory SF subtypes, unrelated to disease classification. Relative Saa3-promoter responses to interleukin 1β, tumour necrosis factor α and TLR4 agonist were significantly increased in OA/RA SF with a high compared to a low inflammatory profile subtype. Serum stimulation of the Saa3-promoter reporter cell-line could distinguish between healthy and RA patients. CONCLUSION: The Saa3-promoter reporter demonstrates a robust and feasible tool for assessing the course and severity of experimental arthritis and for distinguishing molecularly distinct inflammatory SF subtypes from a heterogeneous patient population.
22037947 Fibrinogen as a key regulator of inflammation in disease. 2012 Jan The interaction of coagulation factors with the perivascular environment affects the development of disease in ways that extend beyond their traditional roles in the acute hemostatic cascade. Key molecular players of the coagulation cascade like tissue factor, thrombin, and fibrinogen are epidemiologically and mechanistically linked with diseases with an inflammatory component. Moreover, the identification of novel molecular mechanisms linking coagulation and inflammation has highlighted factors of the coagulation cascade as new targets for therapeutic intervention in a wide range of inflammatory human diseases. In particular, a proinflammatory role for fibrinogen has been reported in vascular wall disease, stroke, spinal cord injury, brain trauma, multiple sclerosis, Alzheimer's disease, rheumatoid arthritis, bacterial infection, colitis, lung and kidney fibrosis, Duchenne muscular dystrophy, and several types of cancer. Genetic and pharmacologic studies have unraveled pivotal roles for fibrinogen in determining the extent of local or systemic inflammation. As cellular and molecular mechanisms for fibrinogen functions in tissues are identified, the role of fibrinogen is evolving from a marker of vascular rapture to a multi-faceted signaling molecule with a wide spectrum of functions that can tip the balance between hemostasis and thrombosis, coagulation and fibrosis, protection from infection and extensive inflammation, and eventually life and death. This review will discuss some of the main molecular links between coagulation and inflammation and will focus on the role of fibrinogen in inflammatory disease highlighting its unique structural properties, cellular targets, and signal transduction pathways that make it a potent proinflammatory mediator and a potential therapeutic target.
22587389 Haem oxygenase 1 expression is altered in monocytes from patients with systemic lupus eryt 2012 Aug Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by multiple functional alterations affecting immune cells, such as B cells, T cells, dendritic cells (DCs) and monocytes. During SLE, the immunogenicity of monocytes and DCs is significantly up-regulated, promoting the activation of self-reactive T cells. Accordingly, it is important to understand the contribution of these cells to the pathogenesis of SLE and the mechanisms responsible for their altered functionality during disease. One of the key enzymes that control monocyte and DC function is haem oxygenase-1 (HO-1), which catalyses the degradation of the haem group into biliverdin, carbon monoxide and free iron. These products possess immunosuppressive and anti-inflammatory capacities. The main goal of this work was to determine HO-1 expression in monocytes and DCs from patients with SLE and healthy controls. Hence, peripheral blood mononuclear cells were obtained from 43 patients with SLE and 30 healthy controls. CD14(+) monocytes and CD4(+) T cells were sorted by FACS and HO-1 expression was measured by RT-PCR. In addition, HO-1 protein expression was determined by FACS. HO-1 levels in monocytes were significantly reduced in patients with SLE compared with healthy controls. These results were confirmed by flow cytometry. No differences were observed in other cell types, such as DCs or CD4(+) T cells, although decreased MHC-II levels were observed in DCs from patients with SLE. In conclusion, we found a significant decrease in HO-1 expression, specifically in monocytes from patients with SLE, suggesting that an imbalance of monocyte function could be partly the result of a decrease in HO-1 expression.
21858161 Toll-like receptor 2 induced angiogenesis and invasion is mediated through the Tie2 signal 2011 BACKGROUND: Angiogenesis is a critical early event in inflammatory arthritis, facilitating leukocyte migration into the synovium resulting in invasion and destruction of articular cartilage and bone. This study investigates the effect of TLR2 on angiogenesis, EC adhesion and invasion using microvascular endothelial cells and RA whole tissue synovial explants ex-vivo. METHODS: Microvascular endothelial cells (HMVEC) and RA synovial explants ex vivo were cultured with the TLR2 ligand, Pam3CSK4 (1 µg/ml). Angiopoietin 2 (Ang2), Tie2 and TLR2 expression in RA synovial tissue was assessed by immunohistology. HMVEC tube formation was assessed using Matrigel matrix assays. Ang2 was measured by ELISA. ICAM-1 cell surface expression was assessed by flow cytometry. Cell migration was assessed by wound repair scratch assays. ECM invasion, MMP-2 and -9 expression were assessed using transwell invasion chambers and zymography. To examine if the angiopoietin/Tie2 signalling pathway mediates TLR2 induced EC tube formation, invasion and migration assays were performed in the presence of a specific neutralising anti-Tie2mAb (10 ug/ml) and matched IgG isotype control Ab (10 ug/ml). RESULTS: Ang2 and Tie2 were localised to RA synovial blood vessels, and TLR2 was localised to RA synovial blood vessels, sub-lining infiltrates and the lining layer. Pam3CSK4 significantly increased angiogenic tube formation (p<0.05), and upregulated Ang2 production in HMVEC (p<0.05) and RA synovial explants (p<0.05). Pam3CSK4 induced cell surface expression of ICAM-1, from basal level of 149±54 (MFI) to 617±103 (p<0.01). TLR-2 activation induced an 8.8±2.8 fold increase in cell invasion compared to control (p<0.05). Pam3CSK4 also induced HMVEC cell migration and induced MMP-2 and -9 from RA synovial explants. Neutralisation of the Ang2 receptor, Tie2 significantly inhibited Pam3CSK4-induced EC tube formation and invasion (p<0.05). CONCLUSION: TLR2 activation promotes angiogenesis, cell adhesion and invasion, effects that are in part mediated through the Tie2 signalling pathway, key mechanisms involved in the pathogenesis of RA.