Clinical Signs Of Arthritis Research Articles

AB0984 Detailed Analysis of MRI Lesions in Subjects with ACPA but NO Clinical Signs of Arthritis

BackgroundAutoimmunity develops long before the development of clinically signs of inflammation in patients with rheumatoid arthritis (RA). In this context the appearance of autoantibodies against citrullinated proteins (ACPA) may be...

FRI0225 Introduction of 3D Printing into Rheumatology –Transferring Images from Arthritic Joints into Models

BackgroundThree dimensional (3D) Prototyping allows the creation of individual 3D objects with almost any material. It is a rapid emerging technology, easy to use and quickly accessible.ObjectivesIn this experimental study...

A8.26 Inducible IL-10 secreting CD49b +Treg cells as cell based-therapy for rheumatoid arthritis

BackgroundAdoptive transfer of regulatory T cells (Tregs) is a promising approach to restore tolerance in autoimmune diseases. However based on the heterogeneity of the Tregs, we need to precisely establish...

A4.10 Early bone microarchitecture changes in adjuvant-induced arthritis rats

Background and ObjectivesHallmarks of rheumatoid arthritis (RA) are joint synovitis and subchondral bone erosions, resulting in loss of joint function. However, occurrence and kinetics of periarticular bone loss remain unclear...

OP0054 Complete freund’s adjuvant induces, in interferon-gamma-deficient mice, a chronic inflammatory disease reminiscent of systemic juvenile idiopathic arthritis

BackgroundSystemic juvenile idiopathic arthritis (sJIA) is a disease characterized by arthritis and systemic features such as fever, rash, lymphadenopathy and leukocytosis. The underlying pathogenic mechanism of sJIA is not understood...

Brief Report: Anti–Carbamylated Protein Antibodies Are Present in Arthralgia Patients and Predict the Development of Rheumatoid Arthritis

AbstractObjectiveRecently, we discovered a new autoantibody system in rheumatoid arthritis (RA): anti–carbamylated protein (anti‐CarP) antibodies. These antibodies have value in predicting joint destruction; however, it is not clear whether they are present before the diagnosis of RA and whether they have value as predictors of RA development. Therefore, we studied whether anti‐CarP antibodies are present in patients with arthralgia and whether their presence is associated with the development of RA.MethodsSera from 340 arthralgia patients who did not have clinical signs of arthritis but who were positive for IgM rheumatoid factor (IgM‐RF) and/or anti–cyclic citrullinated peptide 2 (anti–CCP‐2) and 32 healthy controls were tested for anti‐CarP IgG antibodies. Of the patients with arthralgia, 111 were IgM‐RF positive/anti–CCP‐2 antibody negative and 229 were anti–CCP‐2 antibody positive. Patients were observed for the development of RA (based on the 2010 American College of Rheumatology/European League Against Rheumatism classification criteria) during a median followup period of 36 months. Cox proportional hazards regression analysis was performed to compare the risk of developing RA between arthralgia patients who were positive for anti‐CarP antibodies and those who were negative for anti‐CarP antibodies during followup.ResultsAnti‐CarP antibodies were present in the sera of 39% of the patients. One hundred twenty patients developed RA, after a median of 12 months (interquartile range [IQR] 6–24). The presence of anti‐CarP antibodies was associated with the development of RA in the entire arthralgia cohort after correction for RF and anti–CCP‐2 antibody status (hazard ratio 1.56 [95% confidence interval 1.06–2.29], P = 0.023), as well as in the anti–CCP‐2 antibody–positive subgroup (odds ratio 2.231 [95% confidence interval 1.31–3.79], P = 0.003).ConclusionAnti‐CarP antibodies are present in patients with arthralgia, and their presence predicts the development of RA independent of anti–CCP‐2 antibodies.

Combined depletion of interleukin-1 and interleukin-6 does not exceed single depletion of interleukin -1 in TNF-mediated arthritis

Background Previous studies demonstrated a regulatory role of interleukin 1 (IL-1) in inflammatory cartilage damage and bone destruction in human tumour necrosis factor transgenic (hTNFtg) mice, an animal model for rheumatoid arthritis. Moreover, blocking of IL-6 has been shown to reduce local bone erosions in this model. Therefore the authors wanted to investigate the effect of a combined depletion of IL-1 and IL-6 on the development and severity of inflammatory, erosive arthritis. Methods The authors first crossed IL-1α and s deficient (IL-1 −/− ) mice with IL-6 −/− mice to generate IL-1 −/− IL-6 −/− double knockout mice. The authors next intercrossed these animals with arthritogenic hTNFtg mice to receive IL-1 −/− IL-6 −/− hTNFtg mice. The authors weekly assessed clinical signs of arthritis in hTNFtg, IL-1 −/− hTNFtg mice, IL-6 −/− hTNFtg mice and IL-1 −/− IL-6 −/− hTNFtg mice starting from week 4 after birth until week 16. The authors stained decalcified paw sections from all four genotypes with H&E to determine the amount of inflammatory synovial pannus formation, with tartrate-resistant acid phosphatase (TRAP) to evaluate the number of synovial osteoclasts and the occurrence of subchondral bone erosions, with toluidine-blue to assess articular cartilage damage. Quantitative analysis of histopathological changes were performed using the Osteomeasure Software System. Results The authors found a significant reduction in the clinical signs of arthritis, indicated by an increase of paw swelling and a decrease in grip strength, in IL-1 −/− IL-6 −/− hTNFtg mice when compared to their hTNFtg littermates. In line with these findings the authors observed a significant decrease in synovial inflammation in IL-1 −/− IL-6 −/− hTNFtg mice when compared to hTNFtg animals. Moreover, the number of synovial TRAP+ osteoclasts was markedly diminished in IL-1 −/− IL-6 −/− hTNFtg mice and reduced osteoclast formation was accompanied by significantly less subchondral bone erosions. Additionally, the authors found a conserved articular cartilage structure showing almost no cartilage degradation in IL-1 −/− IL-6 −/− hTNFtg mice compared to their hTNFtg littermates. In IL-1 −/− IL-6 −/− hTNFtg mice clinical, as well as, histological signs of disease, including joint inflammation, bone destruction and cartilage damage were also significantly diminished when compared to IL-6 −/− hTNFtg mice. However, by comparing IL-1 −/− IL-6 −/− hTNFtg mice with IL-1 −/− hTNFtg mice the authors found a similar reduction on synovial inflammation, as well as subchondral bone erosions and articular cartilage destruction. Conclusion The phenotype of IL-1 −/− IL-6 −/− hTNFtg mice does not differ from IL-1 −/− hTNFtg animals indicating no synergistic effects when IL-1 and IL-6 is simultaneously blocked in TNF mediated arthritis.

Comparative analysis of the therapeutic potential of two inducible Treg cell populations in experimental model of arthritis

Backgroundand objectivesAdoptive cell transfer of T regulatory (Treg) cells is a promising approach to restore tolerance in autoimmune disease. However the various type of Tregs, their doses of injection and...

The clinical significance of antibody determination to cyclic citrullinated peptides in systemic sclerosis

Anti-citrullinated peptides antibodies (ACPA) are present in 80% of sera of rheumatoid arthritis (RA) patients with high specificity for diagnosis and prediction for the development of early erosive arthritis. A few studies have reported a low frequency ACPA in systemic sclerosis (SSc) patients with the presence of arthritis. The aim of our study was to determine the frequency of ACPA in systemic sclerosis (SSc) patients, their correlation with clinical manifestations and radiographic features. The study included 82 patients with SSc, mean age 54.4 years, 59 with the limited (ISSc) and 23 with the diffuse (dSSc) form of the disease. The control group included 28 healthy age and sex matched subjects. ACPA and rheumatoid factor (RF) were determined in all SSc patients and healthy subjects in whom standard radiography of hands and wrists was also done. The presence of ACPA was detected in 11 (13.4%) of SSc patients. Their level was not increased in any of the controls. Positive RF was found in 15.9% of SSc patients. Arthritis was present in 17.1%, as well as marginal bone erosions. There was a statistically significant association between positive ACPA and arthritis (p < 0.0001) and positive ACPA and marginal bone erosions (p = 0.0002). The research confirmed the correlation between ACPA with clinical signs of arthritis and radiographic damage of hand joints. ACPA is a useful diagnostic marker in the identification of SSc patients with arthritis and anatomic bone damage enabling the use of adequate therapy in order to prevent joint damage and poor quality of life.

IL-17RA Signaling Amplifies Antibody-Induced Arthritis

ObjectiveTo investigate the role of IL-17RA signaling in the effector phase of inflammatory arthritis using the K/BxN serum-transfer model.MethodsWild-type and Il17ra−/− mice were injected with serum isolated from arthritic K/BxN mice and their clinical score was recorded daily. Mice were also harvested on days 12 and 21 and ankles were analyzed for cytokine and chemokine mRNA expression by qPCR on day 12 and for bone and cartilage erosions by histology on day 21, respectively. The induction of cytokine and chemokine expression levels by IL-17A in synovial-like fibroblasts was also analyzed using qPCR.Results Il17ra−/− mice were partially protected from clinical signs of arthritis and had markedly fewer cartilage and bone erosions. The expression of several pro-inflammatory mediators, including the chemokines KC/CXCL1, MIP-2/CXCL2, LIX/CXCL5 MIP-1γ/CCL9, MCP-3/CCL7, MIP-3α/CCL20, the cytokines IL-1β, IL-6, RANKL and the matrix metalloproteinases MMP2, MMP3, and MMP13 were decreased in the ankles of Il17ra−/− mice compared to wild-type mice. Many of these proinflammatory genes attenuated in the ankles of Il17ra−/− mice were shown to be directly induced by IL-17A in synovial fibroblasts in vitro.ConclusionsIL-17RA signaling plays a role as an amplifier of the effector phase of inflammatory arthritis. This effect is likely mediated by direct activation of synovial fibroblasts by IL-17RA to produce multiple inflammatory mediators, including chemokines active on neutrophils. Therefore, interrupting IL-17RA signaling maybe a promising pharmacological target for the treatment of inflammatory arthritis.

Gadd45β deficiency in rheumatoid arthritis: Enhanced synovitis through JNK signaling

AbstractObjectiveJNK‐mediated cell signaling plays a critical role in matrix metalloproteinase (MMP) expression and joint destruction in rheumatoid arthritis (RA). Gadd45β, which is an NF‐κB–regulated gene, was recently identified as an endogenous negative regulator of the JNK pathway, since it could block the upstream kinase MKK‐7. This study was carried out to evaluate whether low Gadd45β expression in RA enhances JNK activation and overproduction of MMPs in RA, and whether Gadd45β deficiency increases arthritis severity in passive K/BxN murine arthritis.MethodsActivation of the NF‐κB and JNK pathways and Gadd45β expression were analyzed in human synovium and fibroblast‐like synoviocytes (FLS) using quantitative polymerase chain reaction, immunoblotting, immunohistochemistry, electrophoretic mobility shift assay, and luciferase reporter constructs. Gadd45β−/− and wild‐type mice were evaluated in the K/BxN serum transfer model of inflammatory arthritis, and clinical signs of arthritis, osteoclast formation, and bone erosion were assessed.ResultsExpression levels of the Gadd45β gene and protein were unexpectedly low in human RA synovium despite abundant NF‐κB activity. Forced Gadd45β expression in human FLS attenuated tumor necrosis factor–induced signaling through the JNK pathway, reduced the activation of activator protein 1, and decreased the expression of MMP genes. Furthermore, Gadd45β deficiency exacerbated K/BxN serum–induced arthritis in mice, dramatically increased signaling through the JNK pathway, elevated MMP3 and MMP13 gene expression in the mouse joints, and increased the synovial inflammation and number of osteoclasts.ConclusionDeficient Gadd45β expression in RA can contribute to activation of JNK, exacerbate clinical arthritis, and augment joint destruction. This process can be mitigated by enhancing Gadd45β expression or by inhibiting the activity of JNK or its upstream regulator, MKK‐7.

Infective Arthritis: Bacterial 23S rRNA Gene Sequencing as a Supplementary Diagnostic Method

Consecutively collected synovial fluids were examined for presence of bacterial DNA (a 700-bp fragment of the bacterial 23S rRNA gene) followed by DNA sequencing of amplicons, and by conventional bacteriological methods. One or more microorganisms were identified in 22 of the 227 synovial fluids (9,7%) originating from 17 patients. Sixteen of the patients had clinical signs of arthritis. For 11 patients molecular and conventional bacterial examinations were in agreement. Staphylococcus aureus, Streptococcus dysgalactiae subspecies equisimilis and Streptococcus pneumoniae, were detected in synovial fluids from 6, 2 and 2 patients, respectively. In 3 patients only 23S rRNA analysis was positive; 2 synovial fluids contained S. dysgalactiae subspecies equisimilis and 1 S. pneumoniae). The present study indicates a significant contribution by PCR with subsequent DNA sequencing of the 23S rRNA gene analysis in recognizing and identification of microorganisms from synovial fluids.

Mechanisms of Disease: genetic susceptibility and environmental triggers in the development of rheumatoid arthritis

Rheumatoid arthritis (RA) is a complex disease in which environmental agents are thought to interact with genetic factors that influence susceptibility. This interaction triggers immunologic events that eventually result in the clinical signs of arthritis. Knowledge of the chain of etiological events that lead to the development of RA is incomplete. In this review, we describe the experimental approaches that are used to address the issue of gene-environment interactions in the etiology of RA, and discuss relevant examples of such interactions. We focus on how smoking, the best-known environmental risk factor for RA, interacts with HLA-DR shared epitope genes, the main genetic risk factors for RA, and result in a high risk of RA in individuals exposed to both of these risk factors. From these and other related findings, we can begin to define the distinct environmental risk factors (such as smoking) that in certain genetic contexts (for example, the presence of HLA-DR shared epitope alleles) can trigger immune reactions (such as autoantibodies to citrullinated peptides) many years before onset of RA, and consider how these immune reactions might contribute to clinical symptoms in a subset of affected patients. Increased knowledge about these and other events involved in the development of RA should enable the design of new tools for suppressing RA pathogenesis before the onset of disease.

Tracking of Proinflammatory Collagen-Specific T Cells in Early and Late Collagen-Induced Arthritis in Humanized Mice

Rheumatoid arthritis is a chronic inflammatory disease associated with certain HLA-DR4 subtypes. The target autoantigen(s) is unknown, but type II collagen (CII) is a candidate, with a single immunodominant DR4-restricted 261-273 T cell epitope (CII(261-273)). In the present study, we have prepared HLA-DR4:CII(261-273) tetramers and analyzed peripheral blood, lymph node, and synovial fluid cells from DR4-transgenic mice with early and late collagen-induced arthritis to draw a fuller picture of the role of CII-reactive Th cells in disease development. Their frequencies increased approximately 20-fold in blood 1-2 wk postimmunization, and even more in acutely arthritic joints. Our data strongly suggest that CII-specific Th cells are necessary, but not sufficient for collagen-induced arthritis. The CII-specific Th cells displayed an activated proinflammatory Th1 phenotype, and their expansion correlated with onset and severity of arthritis and also with anti-CII Ab levels. Surprisingly, shortly after the first clinical signs of arthritis, activated HLA-DR4:CII tetramer(+) cells became undetectable in the synovial fluid and rare in the blood, but persisted in lymph nodes. Consequently, future human studies should focus on patients with early arthritis, and on their synovial cells, to re-evaluate the occurrence and pathogenic importance of CII-specific or other Th cells in rheumatoid arthritis.

Citrullinated Proteins in Arthritis; their Presence in Joints and Effects on Immunogenicity

Autoantibodies directed against citrulline‐containing proteins have an impressive specificity of nearly 100% in RA patients and a suggestive involvement in the pathogenesis. The targeted epitopes are generated by a post‐translational modification catalysed by the calcium‐dependent enzyme peptidyl arginine deaminase that converts the positively charged arginine to polar but uncharged citrullin. The aim of this study was to analyse the presence of citrulline in the joints at different time points of collagen‐induced arthritis in DA rats by immunohistochemistry and to investigate how immunogenicity and arthritogenicity was affected by citrullination of rat serum albumin (RSA) and collagen type II (CII). Our results indicate that citrulline could be detected in joints of arthritic animals, first appearance at the onset of disease and increasing as disease progressed into a chronic state. Unimmunized animals or time points before clinical signs of arthritis were negative. By morphology, we state that some infiltrating macrophages as well as the cartilage surface stain positive for citrulline, while the major source of citrullinated proteins appears to be fibrin depositions. A specific Cit‐RSA T‐cell response was observed in animals challenged by citrullinated RSA, no response was recorded when RSA was used as a stimulus. The IgG analysis reveals not only a response towards the modified protein but also cross‐reactivity to native RSA. No T‐cell or B‐cell response was noted in animals injected with unmodified RSA. Cit‐CII induced a disease with higher incidence and earlier onset than did the native counterpart. We conclude that, in contrast to the human disease, citrulline does not seem to appear before clinical signs. As inflammation proceeds, citrulline is detected specifically in the joints. All other organs investigated were negative. We also conclude that citrullination of a protein can break tolerance and increase its arthritogenic properties.

Reliability of the Ahlbäck classification of knee osteoarthritis

Objective: The aim of the study was to assess the inter-observer reliability and intra-observer reproducibility of the Ahlbäck radiographic classification for knee osteoarthritis (OA). Design: Ninety-six knee radiographs of patients with clinical signs of arthritis were evaluated and classified into five grades of Ahlbäck classification by three observers with different experience. The evaluation was repeated after 1 month. The inter- and intra-rater agreements were assessed by statistical analysis (k and k wcoefficients). Results: The inter-observer agreement was statistically significant, but with low or medium values of the coefficients. The intra-rater agreement was less significant than the inter-rater. Inter- and intra-rater agreement coefficients decreased when the cases of stage V arthritis were excluded from the analysis. The evaluations were influenced by the age and working experiences of each observer. Conclusions: The authors stress that the Ahlbäck classification, as routinely applied, should not be used in orthopaedic surgery without the support of clinical and/or arthroscopic examinations, because of its poor reliability.

TRANCE/RANKL Knockout Mice Are Protected from Bone Erosion in a Serum Transfer Model of Arthritis

There is considerable evidence that osteoclasts are involved in the pathogenesis of focal bone erosion in rheumatoid arthritis. Tumor necrosis factor-related activation-induced cytokine, also known as receptor activator of nuclear factor-kappaB ligand (TRANCE/RANKL) is an essential factor for osteoclast differentiation. In addition to its role in osteoclast differentiation and activation, TRANCE/RANKL also functions to augment T-cell dendritic cell cooperative interactions. To further evaluate the role of osteoclasts in focal bone erosion in arthritis, we generated inflammatory arthritis in the TRANCE/RANKL knockout mouse using a serum transfer model that bypasses the requirement for T-cell activation. These animals exhibit an osteopetrotic phenotype characterized by the absence of osteoclasts. Inflammation, measured by clinical signs of arthritis and histopathological scoring, was comparable in wild-type and TRANCE/RANKL knockout mice. Microcomputed tomography and histopathological analysis demonstrated that the degree of bone erosion in TRANCE/RANKL knockout mice was dramatically reduced compared to that seen in control littermate mice. In contrast, cartilage erosion was present in both control littermate and TRANCE/RANKL knockout mice. These results confirm the central role of osteoclasts in the pathogenesis of bone erosion in arthritis and demonstrate distinct mechanisms of cartilage destruction and bone erosion in this animal model of arthritis.

Inflammation-inducible intra-articular production of human IL-1 receptor antagonist results in a more efficient inhibition of collagen-induced arthritis than does constitutive expression of the same transgene

Background Achieving biologically effective yet safe levels of recombinant anti-inflammatory proteins by gene therapy may require three regulatory features: 1) a basal level that is sufficiently low to avoid or minimise chronic immunosuppression 2) transcriptional regulation over a wide dynamic range, and 3) induced expression levels that are sufficiently high to achieve the desired biological effects. The C3-Tat/HIV promoter construct seems to have these properties.1 In this two-component expression system the complement factor 3 (C3) promoter regulates production of the HIV transactivator of transcription, and the Tat protein then stimulates expression of the desired transgene, which is regulated by the HIV-LTR promoter. Both C3 and HIV LTR promoters are inducible by proinflammatory cytokines. Objectives To achieve disease-inducible expression of recombinant anti-inflammatory proteins in order to allow autoregulation of drug dose by natural homeostatic mechanisms. Methods We compared a disease-inducible, two component expression system (C3-Tat/HIV) with the constitutive immediate early cytomegalovirus (ieCMV) promoter in the polyarticular Collagen-Induced Arthritis (CIA) model in mice. DBA/I mice were immunised with bovine type II collagen and boostered on day 22. On day 22, mice without any clinical signs of arthritis were selected and adenoviral vectors (Ad. CMV-Luc, Ad. CMV-IL-1Ra, or Ad. C3-Tat/HIV-IL-1Ra) that contained luciferase or the human IL-1Ra gene under control of one of the two promoters were used to transfect the synovial lining of both knees. The injected knee joints and ipsilateral paws were then scored for signs of arthritis and at the end histology was taken. Results Inducible promoter-driven IL-1Ra expression resulted in significantly improved inhibition of CIA than did CMV-driven IL-1Ra production. Moreover, overexpression of IL-1Ra in the knee joints also prevented CIA in the ipsilateral paws. Conclusion Our data (1) demonstrate the feasibility of an inducible expression system for producing a recombinant transgene for treatment of arthritis and (2) show that this system is more effective than strong, constitutive transgene expression for preventing collagen-induced arthritis in mice. Reference Varley AW, Geiszler SM, Gaynor RB, Munford RS. A two-component expression system that responds to inflammatory stimuli in vivoin vivo. Nat Biotechnol. 1997;15(10):1002–6

Cytokine mRNA in the joints and draining lymph nodes of rats with adjuvant arthritis and effects of cyclosporin A.

TNF-alpha and IL-1beta promote leukocyte recruitment to arthritic joints and may contribute to cartilage degradation while regulatory cytokines such as IL-4 and IL-1RA may in part determine the course of arthritis. Here we report the pattern of TNF-alpha, IL-1beta, IL-6, IFN-gamma, IL-1RA, and IL-4 mRNA expression, detected by RT/PCR, in the talar joint and draining popliteal lymph node (PLN) of rats with adjuvant arthritis (AA). Levels of TNF-alpha and IFN-gamma mRNA were increased in the PLN before clinical signs of arthritis. This was followed by increases in IL-1beta and IL-1RA mRNA at d9 and IL-6 mRNA at d12. PLN IL-1RA mRNA levels were positively correlated with those of IL-1beta and TNF-alpha throughout d5-d20. IL-4 mRNA levels were highest on days 7 and 20. In the synovium, a small increase in TNF-alpha, IL-1beta, and IL-6 mRNA was detected on d5 then again on d12. Maximal synovial TNF-alpha levels were reached on d20, while IL-1beta peak expression was on d16 and IL-6 on d14. IL-4, IL-1RA, and IFN-gamma mRNA was undetectable in the synovium. Cyclosporin treatment for 4 days, initiated at the height of arthritis, rapidly decreased clinical disease, and decreased migration of neutrophils and T lymphocytes into the joints. Yet no significant effect of CyA was observed on inflammatory cytokine expression, although the correlation between PLN IL-1RA and IL-1beta or TNF-alpha was lost in treated animals. Thus there is a variable pattern of cytokine gene expression in rat AA, the undetectable IL-4 and IFN-gamma mRNA in synovium being analogous to human rheumatoid arthritis.

Inhibition of cartilage degradation in rat collagen-induced arthritis but not adjuvant arthritis by the neutrophil elastase inhibitor MDL 101,146.

The neutrophil elastase inhibitor MDL 101,146 was examined for its anti arthritic effect and to determine the role of neutrophil elastase in collagen-induced arthritis and adjuvant arthritis. The collagen-induced arthritis model was performed in female DA rats immunized on day 0 an 1.7 with chick type II collagen in Freund's incomplete adjuvant. Adjuvant arthritis was induced in female Lewis rats by an intradermal injection of heat-killed Mycobacterium tuberculosis H37RA. The clinical signs of arthritis were assessed, joint swelling was measured using calipers and bone degradation, new bone proliferation, pannus formation and cartilage degradation were evaluated histologically. MDL 101,146 administered orally inhibited the severity of collagen-induced arthritis as measured by a reduction in clinical score and joint swelling. Histological evaluation demonstrated a bone and cartilage sparing effect of MDL 101,146 in the tibio-tarsal joint of animals with collagen-induced arthritis. These results suggest that destruction of the joint in collagen-induced arthritis is at least partially due to neutrophil elastase.