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ID PMID Title PublicationDate abstract
21905017 Overexpression of T-bet gene regulates murine autoimmune arthritis. 2012 Jan OBJECTIVE: To clarify the role of T-bet in the pathogenesis of collagen-induced arthritis (CIA). METHODS: T-bet-transgenic (Tg) mice under the control of the CD2 promoter were generated. CIA was induced in T-bet-Tg mice and wild-type C57BL/6 (B6) mice. Levels of type II collagen (CII)-reactive T-bet and retinoic acid receptor-related orphan nuclear receptor γt (RORγt) messenger RNA expression were analyzed by real-time polymerase chain reaction. Criss-cross experiments using CD4+ T cells from B6 and T-bet-Tg mice, as well as CD11c+ splenic dendritic cells (DCs) from B6 and T-bet-Tg mice with CII were performed, and interleukin-17 (IL-17) and interferon-γ (IFNγ) in the supernatants were measured by enzyme-linked immunosorbent assay. CD4+ T cells from B6, T-bet-Tg, or T-bet-Tg/IFNγ-/- mice were cultured for Th17 cell differentiation, then the proportions of cells producing IFNγ and IL-17 were analyzed by fluorescence-activated cell sorting. RESULTS: Unlike the B6 mice, the T-bet-Tg mice did not develop CIA. T-bet-Tg mice showed overexpression of Tbx21 and down-regulation of Rorc in CII-reactive T cells. Criss-cross experiments with CD4+ T cells and splenic DCs showed a significant reduction in IL-17 production by CII-reactive CD4+ T cells in T-bet-Tg mice, even upon coculture with DCs from B6 mice, indicating dysfunction of IL-17-producing CD4+ T cells. Inhibition of Th17 cell differentiation under an in vitro condition favoring Th17 cell differentiation was observed in both T-bet-Tg mice and T-bet-Tg/IFNγ-/- mice. CONCLUSION: Overexpression of T-bet in T cells suppressed the development of autoimmune arthritis. The regulatory mechanism of arthritis might involve dysfunction of CII-reactive Th17 cell differentiation by overexpression of T-bet via IFNγ-independent pathways.
23137578 Nonserious infections: should there be cause for serious concerns? 2012 Nov Nonserious infections (NSIE) as colds, flu syndromes, and urinary tract infection, are the most common infections seen in patients with immune mediated inflammatory diseases. Yet, little is known about the impact of immunosuppression, particularly with tumor necrosis factor inhibitors (TNFi), on these infections. A systemic review of large, randomized controlled trials was conducted to identify incidence, types, and outcomes of NSIE associated with the most commonly prescribed TNFi: adalimumab, etanercept, and infliximab.
21211590 The cellular immune response to influenza vaccination is preserved in rheumatoid arthritis 2011 Feb 11 OBJECTIVES: Yearly vaccination against influenza is currently recommended to patients with rheumatoid Arthritis (RA). Antibody and cell-mediated responses are both involved in the defense against influenza. Humoral responses to influenza vaccine are impaired in RA patients treated with rituximab (RTX). The objectives of this study were to comparatively assess cell mediated and humoral responses to influenza vaccination in RA patients with or without RTX-induced CD20 B-cell depletion. METHODS: Trivalent influenza subunit vaccine was administered to 46 RA patients and to 16 healthy controls. The RA group included 29 patients treated by RTX and 17 on conventional disease-modifying anti-rheumatic drugs (DMARDs), mostly methotrexate. Peripheral blood mononuclear cells and sera were obtained immediately before and 4-6 weeks after vaccination. Cell-mediated response to influenza antigens was evaluated by flow cytometry for activated CD4 T-cells. Humoral response was evaluated by haemagglutination inhibition assay. RESULTS: Cellular response: Cell-mediated responses were comparable in RTX-treated vs. DMARDs-treated patients. The recall postvaccination CD4+ cellular response was similar in RA patients and healthy controls. A positive correlation was found between CD19+ cell count on the day of vaccination and cellular response in RTX-treated RA patients. Humoral response: The antibody response rate was significantly impaired in the RTX group: being 26.4%, 68.4% and 47.1% in RTX-treated, DMARDs-treated and controls, respectively. CONCLUSION: Cellular immunity to influenza vaccination in RTX-treated patients was similar to DMARDs-treated patients and healthy controls, while humoral immunity was severely impaired. The preservation of cellular immunity may explain the relatively low rate of infection among B-cell depleted patients.
22835281 New insights into the genetics of immune responses in rheumatoid arthritis. 2012 Aug Rheumatoid arthritis (RA) is a common autoimmune disease with a strong genetic component. Numerous aberrant immune responses have been described during the evolution of the disease. In later years, the appearance of anti-citrullinated protein antibodies (ACPAs) has become a hallmark for the diagnosis and prognosis of RA. The post-translational transformation of arginine residues of proteins and peptides into citrulline (citrullination) is a natural process in the body, but for unknown reasons autoreactivity towards citrullinated residues may develop in disposed individuals. ACPAs are often found years before clinical manifestations. ACPAs are present in about 70% of RA patients and constitute an important disease marker, distinguishing patient groups with different prognoses and different responses to various treatments. Inside the human leukocyte antigen (HLA) region, some HLA-DRB1 alleles are strongly associated with their production. Genome-wide association studies in large patient cohorts have defined a great number of single nucleotide polymorphisms (SNPs) outside of the HLA region that are associated with ACPA positive (ACPA+) RA. The SNPs are generally located close to or within genes involved in the immune response or signal transduction in immune cells. Some environmental factors such as tobacco smoking are also positively correlated with ACPA production. In this review, we will describe the genes and loci associated with ACPA+ RA or ACPA- RA and attempt to clarify their potential role in the development of the disease.
21496399 A new chance to maintain remission induced by anti-TNF agents in rheumatoid arthritis pati 2011 Jan The advent of biological therapies represented the beginning of a new era in the therapy of Rheumatoid Arthritis (RA), as demonstrated in several studies, but still many questions about their safety, especially in long term use, and correct administration time remain unanswered. Once remission is achieved, the orientation of clinicians regarding the maintenance of biological therapy or the switch to another immunosuppressive therapy is still uncertain. In our previous study 21 patients affected by RA who reached remission by the use of a combined therapy of anti-TNF drugs and methotrexate (MTX) underwent CyA-MTX combination therapy for maintaining remission state and were evaluated during a 6-month follow-up. The present study aims to investigate these data by a longer follow-up (12 months) and on a larger population. Fifty-three RA patients, with a disease duration of less than 3 years and DAS28<3.2 that reached a level of low disease activity within 6-8 months from the beginning of anti-TNF and methotrexate therapy, were enrolled in the study. By the suspension of anti-TNF therapy, patients underwent A-Cyclosporine (2-3 mg/kg/day) and methotrexate (15mg/week) therapy. DAS28, Pain VAS, Erythrosedimentation rate (ESR), C Reactive Protein (CRP) were all tested at time 0 and every 2 months after the interruption of the anti-TNF therapy and the beginning of A-Cyclosporine and methotrexate therapy, as well as liver and kidney profiles. Side effects were also recorded. Of 53 patients, 50 completed the study with a 12-month follow-up. Twenty-one (42%) patients maintained clinical parameters within low disease activity values at 12 months, while 29 (58%) patients showed an increase in DAS28 and other parameters: 16 (32%) patients at the 6-month control, 13 (26%) patients at the 12-month control. Our data show that 42% of the patients undergoing A-Cyclosporin and Methotrexate therapy maintained low disease activity parameters of rheumatoid arthritis, obtained after 6-8 months of anti-TNF therapy. Further studies on larger populations are necessary in order to confirm such results and identify predictor factors for different responses.
21834067 Blocking of interferon regulatory factor 1 reduces tumor necrosis factor α-induced interl 2011 Nov OBJECTIVE: To examine the role of interferon regulatory factor 1 (IRF-1) in tumor necrosis factor α (TNFα)-induced interleukin-18 binding protein a (IL-18BPa) expression in rheumatoid arthritis synovial fibroblasts (RASFs). METHODS: TNFα-induced IRF-1 expression was assessed by real-time quantitative polymerase chain reaction and Western blotting. The effect of TNFα on IRF-1 was assessed using nuclear and cytoplasmic extracts, Western blots, and immunofluorescence. Chemical inhibitors of NF-κB or MAP kinases were used to analyze the signaling pathways of TNFα-induced IRF-1 expression and IRF-1 nuclear translocation. Control and IRF-1 small interfering RNA (siRNA) were used to analyze the effect of IRF-1 down-regulation on TNFα-induced IL-18BP expression. IL-18BPa expression was assessed by enzyme-linked immunosorbent assay, and IL-18 was assessed at the transcription and bioactivity levels using KG-1 cells. RESULTS: TNFα induced RASF IRF-1 expression at the messenger RNA and protein levels, with a maximal effect at 2 hours (P < 0.05; n ≥ 3). Furthermore, TNFα induced nuclear translocation of IRF-1, with maximal translocation at 2 hours (∼6 fold-induction) (P < 0.05; n = 4). Blocking of the NF-κB or JNK-2 pathways reduced TNFα-induced IRF-1 nuclear translocation by 35% and 50%, respectively (P < 0.05; n ≥ 4). Using siRNA to knock down IRF-1, we observed reduced IL-18BPa expression. Additionally, IL-18 bioactivity was higher when siRNA was used to knock down IRF-1 expression. CONCLUSION: These results show that IRF-1 is a key regulator of IL-18BPa expression and IL-18 bioactivity in RASFs. Regulation of IRF-1 will be a new therapeutic target in RA.
22460142 In vitro and in vivo analysis of a JAK inhibitor in rheumatoid arthritis. 2012 Apr Multiple cytokines play a pivotal role in the pathogenesis of rheumatoid arthritis (RA). The appropriate intracellular signalling pathways must be activated via cytokine receptors on the cell surface, and the tyrosine kinases transduce the first 'outside to in' signals to be phosphorylated after receptor binding to its ligand. Among them, members of the Janus kinase (JAK) family are essential for the signalling pathways of various cytokines and are implicated in the pathogenesis of RA. The in vitro, ex vivo and in vivo effects of a JAK inhibitor CP-690,550 (tofacitinib) for the treatment of RA are reported. In vitro experiments indicated that the effects of tofacitinib were mediated through suppression of interleukin 17 (IL-17) and interferon γ production and proliferation of CD4 T cells, presumably Th1 and Th17. A treatment study was conducted in the severe combined immunodeficiency (SCID)-HuRAg mice, an RA animal model using SCID mice implanted with synovium and cartilage from patients. Tofacitinib reduced serum levels of human IL-6 and IL-8 in the mice and also reduced synovial inflammation and invasion into the implanted cartilage. A phase 2 double-blind study using tofacitinib was carried out in Japanese patients with active RA and inadequate response to methotrexate (MTX). A total of 140 patients were randomised to tofacitinib 1, 3, 5, 10 mg or placebo twice daily and the American College of Rheumatology 20% improvement criteria (ACR20) response rate at week 12, a primary end point, was significant for all tofacitinib treatment groups. Thus, an orally available tofacitinib in combination with MTX was efficacious and had a manageable safety profile. Tofacitinib at 5 and 10 mg twice a day appears suitable for further evaluation to optimise the treatment of RA.
21803747 Treating Rheumatoid Arthritis to Target: multinational recommendations assessment question 2011 Nov AIM: To measure the level of agreement and application of 10 international recommendations for treating rheumatoid arthritis (RA) to a target of remission/low disease activity. METHODS: A 10-point Likert scale (1=fully disagree, 10=fully agree) measured the level of agreement with each of 10 recommendations. A 4-point Likert scale (never, not very often, very often, always) assessed the degree to which each recommendation was being applied in current daily practice. If respondents answered 'never' or 'not very often', they were asked whether they would change their practice according to the particular recommendation. RESULTS: A total of 1901 physicians representing 34 countries participated. Both agreement with and application of recommendations was high. With regard to application of recommendations in daily practice, the majority of responses were 'always' and 'very often'. A significant percentage of participants who were currently not applying these recommendations in clinical practice were willing to change their practice according to the recommendations. CONCLUSION: The results of this survey demonstrated great support of 'Treating RA to Target' recommendations among the international rheumatology community. Additional efforts may be needed to encourage application of the recommendations among certain clinicians who are resistant to changing their practice.
21810051 Chronic Lyme disease: the controversies and the science. 2011 Jul The diagnosis of chronic Lyme disease has been embroiled in controversy for many years. This is exacerbated by the lack of a clinical or microbiologic definition, and the commonality of chronic symptoms in the general population. An accumulating body of evidence suggests that Lyme disease is the appropriate diagnosis for only a minority of patients in whom it is suspected. In prospective studies of Lyme disease, very few patients go on to have a chronic syndrome dominated by subjective complaints. There is no systematic evidence that Borrelia burgdorferi, the etiology of Lyme disease, can be identified in patients with chronic symptoms following treated Lyme disease. Multiple prospective trials have revealed that prolonged courses of antibiotics neither prevent nor alleviate such post-Lyme syndromes. Extended courses of intravenous antibiotics have resulted in severe adverse events, which in light of their lack of efficacy, make them contraindicated.
23264071 Association of the CTLA-4 +49A/G polymorphism with rheumatoid arthritis in Chinese Han pop 2013 Mar Cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) is an important molecule in the regulation of T cells, so the CTLA-4 gene has been considered as a strong candidate associated with T cell-mediated autoimmune diseases such as rheumatoid arthritis (RA). CTLA-4 has many variants and polymorphic forms, among which the +49A/G polymorphism, causing a non-synonymous substitution, has been studied most. However, previous studies of the association between the +49A/G polymorphism of the CTLA-4 gene and RA have provided conflicting results. The aim of this study was to determine the potential relationship of the CTLA-4 +49A/G polymorphism and the risk of RA in Chinese Han population. TaqMan assay was used to genotype the +49A/G polymorphism in 1,489 RA patients and 1,200 healthy controls. Furthermore, a meta-analysis of all studies relating this polymorphism in Chinese population to the risk of RA was performed. The genotype and allele frequencies of the CTLA-4 +49A/G in patients with RA differed significantly from those of controls (P = 0.03 and P = 0.007, respectively). The meta-analysis also revealed that the CTLA-4 +49G allele was associated with an increased risk of RA in Chinese population. Our results suggested that the CTLA-4 gene might contribute to the pathogenesis of RA, and the +49A/G polymorphism of this gene was a risk factor associated with increased RA susceptibility in Chinese Han population.
20972592 Sarcoid-like granulomatosis in patients treated with anti-TNFα factors. A case report and 2011 Apr This report describes a 56-year-old woman who developed granulomatous lesions consistent with sarcoidosis during adalimumab therapy for rheumatoid arthritis. Cervical and axillary lymphadenopathy developed approximately 21 months after adalimumab administration. Non-caseating epithelioid cell granulomas consistent with sarcoidosis were detected both in an axillary lymph node specimen and in the bone marrow. Diseases showing similar histologic changes, especially tuberculosis, were excluded, and a diagnosis of sarcoidosis was made. Adalimumab was discontinued, and recovery was observed. The current case is, to our knowledge, the first to describe adalimumab-induced non-caseating granulomas in lymph nodes and bone marrow without pulmonary involvement in a patient treated for rheumatoid arthritis.
22433439 PI3 kinase δ is a key regulator of synoviocyte function in rheumatoid arthritis. 2012 May Class I phosphoinositide 3 kinase (PI3K) δ is a promising therapeutic target for rheumatoid arthritis (RA) because of its contribution to leukocyte biology. However, its contribution in fibroblasts has not been studied as a mechanism that contributes to efficacy. We investigated the expression and function of PI3Kδ in synovium and cultured fibroblast-like synoviocytes (FLS). Immunohistochemistry demonstrated that PI3Kδ is highly expressed in RA synovium, especially in the synovial lining. Using quantitative PCR and Western blot analysis, we found that PI3Kδ mRNA and protein expression is higher in RA than in osteoarthritis (OA) synovium. PI3Kδ was also expressed in cultured FLS, along with PI3Kα and PI3Kβ, whereas PI3Kγ was not detectable. PI3Kδ mRNA expression was selectively induced by inflammatory cytokines tumor necrosis factor (TNF) and interleukin-1 (IL-1) but not by growth factors platelet-derived growth factor (PDGF) and transforming growth factor β (TGFβ). The use of inhibitors that block individual PI3K isoforms, including the novel selective PI3Kδ inhibitor INK007, showed that PI3Kδ is required for PDGF- and TNF-induced Akt activation. PI3Kδ inhibition also diminished PDGF-mediated synoviocyte growth and sensitized cells to H(2)O(2)-induced apoptosis. These data are the first documentation of increased PI3Kδ expression in both RA synovium and cultured synoviocytes. Furthermore, these are the first data demonstrating that PI3Kδ is a major regulator of PDGF-mediated fibroblast growth and survival via Akt. Thus, targeting PI3Kδ in RA could modulate synoviocyte function via anti-inflammatory and disease-altering mechanisms.
21163672 Elevation of human tumor necrosis factor-like weak inducer of apoptosis in peripheral bloo 2011 Mar Tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK) is a recently identified proinflammatory cytokine of the TNF superfamily. Studies have indicated that TWEAK plays an important role in renal, vascular injury and immune disease. The aim of this study was to explore the expression of the TWEAK in peripheral blood mononuclear cells (PBMCs) and analyze the correlation between TWEAK and disease activity and renal damage of SLE. The expression of TWEAK in PBMCs was determined by RT-PCR and western blot. SLE disease activity was evaluated by Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) 2000 score. Next were analyzed the correlations of TWEAK mRNA and protein to serum IL-10, MCP-1 and some laboratory parameters of SLE disease activity. Subjects comprised 48 patients with SLE including 25 patients with renal damage and 23 without, 20 patients with rheumatoid arthrithis (RA) and 15 healthy controls. The results showed that TWEAK expressions in PBMCs from SLE patients were significantly higher than that in RA patients or healthy controls, especially higher in those patients with renal disease. Elevated production of TWEAK is correlated positively and significantly with SLEDAI, proteinuria, serum anti-dsDNA, IL-10 and MCP-1, but inversely associated with serum complements. Our results suggested that TWEAK in PBMCs is positively related to SLE disease activity and might be involved in the pathogenesis of SLE.
21557212 Synovial fibroblasts promote immunoglobulin class switching by a mechanism involving BAFF. 2011 Jul Fibroblast-like synoviocytes (FLSs) are important actors in rheumatoid arthritis (RA) pathogenesis. The autoimmune nature of RA is attributed to autoantibody production, which confers to B cells a predominant role in RA. Several arguments support an induction of class switch recombination (CSR) in RA synovium, causing--in conjunction with somatic hypermutation--the production of potentially pathogenic IgG. To determine whether RA FLSs can directly promote CSR and to analyze the role of external factors like TLR signals and BAFF (B cell activating factor) family cytokines in this FLS-B cell crosstalk, we performed cocultures of blood B cells (from normal individuals or RA patients) with RA FLSs and analyzed CSR induction by quantification of AICDA (encoding activation-induced cytidine deaminase, AID) and switch circular transcripts expression, and IgG secretion. RA FLSs--and to a lesser extent osteoarthritis or control FLSs--promoted CSR, and TLR3 stimulation potentialized it. In addition, induction of CSR by RA FLSs was totally dependent on cell-cell contact in basal conditions, and partially dependent in the case of TLR3 stimulation. Finally, we showed that the mechanism by which RA FLSs induce CSR is mostly BAFF-dependent. Our results support the hypothesis that CSR can be induced outside the ectopic lymphoid structures in RA.
22221886 Treatment strategies for periprosthetic infections after primary elbow arthroplasty. 2012 Aug BACKGROUND: The goal of this study was to investigate the outcome of different surgical procedures (debridement and retention vs 1- or 2-stage exchange) together with a well-defined antimicrobial regimen. MATERIALS AND METHODS: A total of 236 consecutive patients underwent 262 primary elbow arthroplasties between January 1994 and December 2007. We observed 20 episodes of periprosthetic infections in 19 patients and placed them into 3 groups according to the occurrence of infection after index surgery. A total of 9 early infections (<3 months), 1 delayed infection (3-24 months), and 10 late infections (>24 months) were observed. The treatment among those 3 groups was compared, and the outcome was assessed with a mean follow-up of 60.2 months. RESULTS: In the group with early infections (n = 9), 8 cases were treated by irrigation and debridement and 1 case was treated by a 2-stage exchange without recurrence of infection. The mean Mayo Elbow Performance Score improved from 48.3 points (range, 30-75 points) to 91.7 points (range, 85-100 points). The delayed infection was treated by 1-stage exchange without recurrence of infection. For late infections (n = 10), 3 cases presented recurrence of infection after debridement and irrigation, and the mean Mayo Elbow Performance Score remained nearly unchanged, from 60 points (range, 45-80 points) to 65 points (range, 50-80 points). Eradication of infection could be achieved by staged revision and in 3 cases by debridement. CONCLUSION: Both debridement with retention and staged reimplantation are highly successful for appropriate indications. Staged revisions are successful even against biofilm-active microorganisms, but a prosthesis-free interval of at least 3 months is recommended.
22915618 Multiple cytokines and chemokines are associated with rheumatoid arthritis-related autoimm 2013 Jun OBJECTIVE: We investigated whether rheumatoid arthritis (RA)-related autoantibodies were associated with systemic inflammation in a prospective cohort of first-degree relatives (FDRs) of RA probands, a population without RA but at increased risk for its future development. METHODS: We studied 44 autoantibody positive FDRs, of whom 29 were rheumatoid factor (RF) positive, 25 were positive for the high risk autoantibody profile (HRP), that is, positive for anti-cyclic citrullinated peptide and/or for at least two RF IgM, IgG or IgA isotypes, and nine FDRs who were positive for both; and 62 FDRs who were never autoantibody positive. Twenty-five cytokines/chemokines were measured using a bead-based assay in serum. As a comprehensive measure of inflammation, we calculated a Cytokine Score by summing all cytokine/chemokine levels, weighted by their regression coefficients for RA-autoantibody association. We compared C-reactive protein, individual cytokines/chemokines and Cytokine Score to the outcomes: positivity for RF and for the HRP using logistic regression. RESULTS: Adjusting for age, sex, ethnicity and ever smoking, the Cytokine Score and levels of IL-6 and IL-9 were associated with both RF and HRP. IL-2, granulocyte macrophage-colony stimulating factor (GM-CSF), and interferon (IFN)-γ were associated with HRP only. Associations between the Cytokine Score and RF and HRP positivity were replicated in an independent military personnel cohort. CONCLUSIONS: In first-degree relatives of patients with RA, RA-related autoimmunity is associated with inflammation, as evidenced by associations with multiple cytokines and chemokines.
21210288 Predominance of IgG1 and IgG3 subclasses of autoantibodies to peptidylarginine deiminase 4 2011 Apr Analysis of IgG subclass distribution of antibodies may provide insights into the mechanisms driving antibody production. Here, we have first determined IgG subclass distribution of anti-recombinant peptidylarginine deiminase 4 (anti-hPADI4) antibodies in sera from patients with rheumatoid arthritis (RA). Sera from 103 RA patients were screened to IgG anti-PADI4 using recombinant antigens. For positive samples, the subclass distribution of IgG anti-hPADI4 was determined by means of establishing the equipotency of four HRP-labeled IgG subclass-specific monoclonal antibodies. The subclass profiles were compared among individuals with different disease status. Thirty-three out of 103 RA patients were determined as IgG anti-hPADI4-positive. As expressed by percentage levels to total IgG anti-hPADI4 activity, IgG1 and IgG3 were determined to be the predominant subclasses of anti-hPADI4. Furthermore, distinct subclass distribution patterns were observed in patients with different disease status. The IgG subclass distribution of anti-hPADI4 indicates that a leading T lymphocyte-regulated IgG1 and IgG3 responses may contribute to a better understanding of the role of anti-PADI4 in RA.
21159824 Association of EMCN with susceptibility to rheumatoid arthritis in a Japanese population. 2011 Feb OBJECTIVE: Endomucin, an endothelial-specific sialomucin, is thought to facilitate "lymphocyte homing" to synovial tissues, resulting in the major histopathologies of rheumatoid arthritis (RA). We examined the association between RA susceptibility and the gene coding endomucin, EMCN. METHODS: Association studies were conducted with 2 DNA sample sets (initial set of 1504 patients, 752 controls; and validation set, 1113 patients, 940 controls) using 6 tag single-nucleotide polymorphisms (SNP) from the Japanese HapMap database. Immunohistochemistry for the expression of endomucin was conducted with synovial tissues from 4 patients with RA during total knee arthroplasty. Electromobility shift assays were performed for the functional study of identified polymorphisms. RESULTS: Within the initial sample set, the strongest evidence of an association with RA susceptibility was SNP rs3775369 (OR 1.20, p = 0.0075). While the subsequent replication study did not initially confirm the observed significant association (OR 1.13, p = 0.062), an in-depth stratified analysis revealed significant association in patients testing positive to anti-cyclic citrullinated peptide (anti-CCP) antibody in the replication data set (OR 1.15, p = 0.044). Investigating 2 sample sets, significant associations were detected in overall and stratified samples with anti-CCP antibody status (OR 1.17, p = 0.0015). Positive staining for endomucin was detected in all patients. The allele associated with RA susceptibility had a higher binding affinity for HEK298-derived nuclear factors compared to the nonsusceptible allelic variant of rs3775369. CONCLUSION: A significant association between EMCN and RA susceptibility was detected in our Japanese study population. The EMCN allele conferring RA susceptibility may also contribute to the pathogenesis of RA.
21195737 Mucin from rheumatoid arthritis synovial fluid enhances interleukin-6 production by human 2011 Mar The carbohydrate chains represented by mucins (MUCs) are expressed by a variety of normal and malignant secretory epithelial cells and induce a variety of immunoreactions. To find new mucins related to the pathogenesis of rheumatoid arthritis (RA), we examined high-molecular-weight molecules inducing cytokines on human peripheral blood mononuclear cells (PBMCs) in synovial fluid from affected joints. We found a high-molecular-weight substance that induces interleukin 6 production on PBMCs in RA synovial fluid on gel filtration. MUC-1 was present in the resulting fractions, although they had been purified by CsCl density gradient centrifugation. We also found that MUC-1 was expressed on synovial cells and infiltrating inflammatory mononuclear cells on the sublining layer and lymphoid follicles in RA synovial tissues. CD68-positive superficial synovial cells colocalized with MUC-1 and CD68-positive macrophages were in contact with MUC-1-positive mononuclear cells. These findings imply that mucins, including MUC-1, may be related to immunoinflammatory reactions in the pathogenesis of RA.
20091035 Safety of biologic agents after rituximab therapy in patients with rheumatoid arthritis. 2011 Apr The safety of other biologic therapies in rheumatoid arthritis (RA) following B cell-depletion therapy with rituximab has not been established. This retrospective chart review of patients attending an outpatient rheumatology clinic aimed to assess the incidence of adverse events in patients receiving biologic agents to treat RA after an inadequate response or intolerance to rituximab. The charts of 22 patients (18 female; mean age 59 years) were reviewed. Duration of RA was >2 years. Before rituximab, patients had failed one (n = 10), two (n = 4) or three (n = 7) biologic therapies: 1 patient started on rituximab as a first-line biologic. Eighteen patients stopped rituximab due to an inadequate clinical response, while four patients stopped due to adverse events. The mean time to starting a new biologic after rituximab was 4 months, although five patients were started within 1 month of the last rituximab infusion. Abatacept (41%) was the most common biologic used after rituximab. The mean follow-up time from the last rituximab infusion was 14 months. Adverse events occurring after rituximab therapy, but before initiation of a new biologic, included disseminated herpes zoster and aseptic meningitis (both required hospitalization). Adverse events recorded after starting a new biologic post-rituximab included rash, carbuncle, upper respiratory tract infection, urinary tract infection, pneumonia, and eczema, but none was classified as serious. Most of these events occurred in patients receiving abatacept. In conclusion, in this retrospective analysis, no serious adverse events were recorded in patients who received biologic agents following rituximab therapy.