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ID PMID Title PublicationDate abstract
19404957 Efficacy, pharmacodynamics, and safety of VX-702, a novel p38 MAPK inhibitor, in rheumatoi 2009 May OBJECTIVE: To assess the efficacy and safety of VX-702, a p38 MAPK inhibitor, in patients with active, moderate-to-severe rheumatoid arthritis (RA). METHODS: Two 12-week, double-blind, placebo-controlled studies of VX-702 were conducted in patients with active, moderate-to-severe RA. In the VeRA study, 313 patients received placebo or 2 daily doses of VX-702. In Study 304, 117 patients received placebo, daily VX-702, or twice weekly VX-702 in addition to concomitant methotrexate (MTX). Study end points included the proportion of patients meeting the American College of Rheumatology 20% improvement criteria (an ACR20 response), ACR50 and ACR70 responses, changes in the serum levels of biomarkers of inflammation, and safety assessments. RESULTS: The numerically superior ACR20 response rates among patients receiving VX-702 compared with those receiving placebo in both studies did not reach pairwise statistical significance at the highest doses in either study. At week 12 in the VeRA study, ACR20 response rates were 40%, 36%, and 28% among patients receiving 10 mg of VX-702, 5 mg of VX-702, and placebo, respectively. In Study 304, the response rates were 40%, 44%, and 22% for patients receiving 10 mg VX-702 daily plus MTX, 10 mg VX-702 twice weekly plus MTX, and placebo, respectively. Reductions in the levels of C-reactive protein, soluble tumor necrosis factor receptor p55, and serum amyloid A were observed as early as week 1 in both studies, but these levels rapidly returned to baseline values by week 4. The overall frequency of adverse events was similar between the VX-702 and placebo groups. In the VeRA study, serious infections were more frequent in the VX-702 groups compared with the placebo group (2.4% versus 0%) but not in Study 304 (2.6% versus 4.9%). CONCLUSION: The modest clinical efficacy plus the transient suppression of biomarkers of inflammation observed in this study suggest that p38 MAPK inhibition may not provide meaningful, sustained suppression of the chronic inflammation seen in RA.
19758160 Regulatory B cells in autoimmune diseases: how do they work? 2009 Sep B lymphocytes contribute to the pathogenesis of autoimmune disorders since B-cell depletion treatment improves such diseases. However, B cells seem ambivalent. Murine strains of nonorgan-specific as well as organ-specific autoimmune conditions present with aggravated symptoms when B cells are depleted. It is thus likely that some B cells are pathogenic while other have regulatory function. There is not only one regulatory B cell (Breg) subset, but different types of Breg cells. Regulatory function can thus be ascribed to autoreactive B cells, marginal zone B cells, transitional type 2-like B cells, or CD5(+) B cells. Regulatory activity is induced only following cell activation through a B-cell receptor, CD40, and/or TLR9. Regulatory effects are then mediated by a soluble agent, such as IL-10, and/or direct cell-to-cell contacts that involve CD40 or B7 co-stimulatory molecules. Targeted cells also vary from one disease to another. Antigen-specific autoreactive T cells, dendritic cells, macrophages, and regulatory T lymphocytes can thus be either inhibited or activated to finally modulate the autoimmune response. Taken as a whole, it appears that Breg cells participate in the control of autoimmunity within a complex cellular network that may differ for each pathology. Adapted stimulation and control of regulatory activity would thus be a prerequisite to an efficient usage of these B cells as an alternative therapy for autoimmune diseases.
20974134 POSH promotes cell survival in Drosophila and in human RASF cells. 2010 Nov 19 In Drosophila, Eiger, a tumor necrosis factor α (TNFα) superfamily ligand, induces cell death by activating the c-Jun N-terminal kinase (JNK) pathway. Here, we report that overexpression of Plenty of SH3s (POSH) suppresses Eiger-induced cell death and produces highly deformed tissues. These results imply that high levels of POSH protect tissues from cell death. In humans, rheumatoid arthritis synovial fibroblasts (RASF) are generally resistant to apoptosis. We show that POSH is expressed at relatively high levels in RASF, and its reduction by RNAi sensitizes these cells to Fas-mediated apoptosis. Thus, we demonstrate that POSH promotes cell survival in Drosophila and in human RASF.
20722764 The tortoise and the hare: slowly evolving T-cell responses take hastily evolving KIR. 2010 Nov The killer cell immunoglobulin-like receptor (KIR) locus comprises a variable and rapidly evolving set of genes encoding multiple inhibitory and activating receptors. The activating receptors recently evolved from the inhibitory receptors and both bind HLA class I and probably also class I-like structures induced by viral infection. Although generally considered natural killer (NK) cell receptors, KIR are also expressed by a large fraction of effector memory T cells, which slowly accumulate during human life. These effector memory cells are functionally similar to NK cells, as they are immediate effector cells that are cytotoxic and produce IFN-γ. However, different rules apply to NK and T cells with respect to KIR expression and function. For example, KIR tend to modulate signals driven by the T-cell receptor (TCR) rather than to act independently, and use different signal transduction pathways to modulate only a subset of effector functions. The most important difference may lie in the rules governing tolerance: while NK cells with activating KIR binding self-HLA are hyporesponsive, the same is unlikely to apply to T cells. We argue that the expression of activating KIR on virus-specific T cells carrying TCR that weakly cross-react with autoantigens can unleash the autoreactive potential of these cells. This may be the case in rheumatoid arthritis, where cytomegalovirus-specific KIR2DS2(+) T cells might cause vasculitis. Thus, the rapid evolution of activating KIR may have allowed for efficient NK-cell control of viruses, but may also have increased the risk that slowly evolving T-cell responses to persistent pathogens derail into autoimmunity.
20871129 Certolizumab pegol in the treatment of rheumatoid arthritis: a comprehensive review of its 2011 Feb Biological agents, including TNF inhibitors, have revolutionized the treatment of RA in recent years. Certolizumab pegol (CZP) is a novel pegylated anti-TNF approved for the treatment of adult patients with moderately to severely active RA. This article provides an overview of three published clinical trials of CZP in RA in patients with active disease who have shown an inadequate response to DMARDs, including MTX: RA prevention of structural damage (RAPID) 1 and 2, which evaluated the efficacy and safety of CZP added to MTX when dosed every 2 weeks, and efficacy and safety of CZP - 4 weekly dosage in rheumatoid arthritis (FAST4WARD), which evaluated CZP monotherapy when dosed every 4 weeks. In the trials, CZP plus MTX or as monotherapy significantly improved the signs and symptoms of RA and RA disease activity, and CZP plus MTX significantly inhibited the progression of radiographic joint damage as early as Week 16 of the treatment. In addition, CZP treatment significantly improved patient-reported outcome measures, providing significant reductions in pain and fatigue and improvements in physical function as early as Week 1 of treatment; improvements in health-related quality of life were evident at the first assessment at Week 12. CZP treatment improved productivity at work, significantly reducing the number of days of missed work as well as the number of days with reduced productivity, and also increased productivity within the home and improved participation in family, social and leisure activities. CZP was generally well tolerated when used either as monotherapy or added to MTX; most adverse events were mild or moderate. Taken together, the results of these trials suggest that CZP is an effective new option for the treatment of RA.
20676016 Short-term results of the Oxford phase 3 unicompartmental knee arthroplasty for medial art 2010 OBJECTIVES: We evaluated short-term results of the Oxford phase 3 unicompartmental knee arthroplasty (UKA) in patients with medial compartment arthritis. METHODS: The study included 38 patients (28 females, 10 males; mean age 67 years; range 56 to 75 years) who underwent UKA for isolated medial knee osteoarthritis. At the time of surgery, 28 patients were in the age group of 56-64 years, and 10 patients were in the age group of 65-75 years. All the patients had Ahlbäck grade 2 primary medial compartment arthritis that had been unresponsive to conservative treatment. None of the patients had symptoms of patellofemoral arthrosis. Patients underwent UKA with the Oxford phase 3 cemented meniscal-bearing unicondylar prosthesis using minimally invasive surgery. The results were assessed preoperatively and at final controls according to the Knee Society clinical and functional rating system. Postoperative radiographic evaluations were made according to the Oxford criteria. The mean follow-up period was 24 months (range 18 to 32 months). RESULTS: The mean preoperative active knee flexion increased from 121.8 degrees (range 110 degrees to 130 degrees ) to 130.9 degrees (range 120 degrees to 140 degrees) postoperatively (p<0.05). There was no limitation in knee extension both pre- and postoperatively. The mean preoperative and postoperative knee scores were 64.6 (range 47 to 80) and 97.5 (range 89 to 100), and the mean functional scores were 59.6 (range 45 to 80) and 92.1 (range 70 to 100), respectively (p<0.05). All the patients had an excellent knee score, while functional scores were excellent in 27 patients (71.1%) and good in 11 patients (28.9%). Postoperative radiographic measurements showed that the position of the femoral components was within acceptable ranges in all the patients with a mean of 3 degrees valgus (range 5 degrees valgus to 8 degrees varus) and 0.5 degrees extension (range 3 degrees extension to 2 degrees flexion). The positioning of the femoral components in relation to the mechanical axis was central in 30 patients and 2-mm lateral (range 2 mm medial to 4 mm lateral) in eight patients. The position of the tibial components was also within acceptable ranges in all the patients with a mean of 1.5 degrees varus (range 2 degrees varus to 2 degrees valgus) and a mean posterior inclination of 6.2 degrees (range 5 degrees to 7 degrees). All the tibial components showed full congruency with the medial, lateral, anterior, and posterior planes, except for one which had a 4-mm undersizing in the anterior plane. The polyethylene insert was central and parallel to the tibial component in all the patients. No osteophytes or cement debris that might lead to impingement were observed. All the components remained in position until the final controls. Complications such as insert dislocation, infection, pulmonary embolism, deep venous thrombosis, or neurovascular injury were not observed. None of the patients required revision surgery. CONCLUSION: Our findings show that, with proper patient selection and strict adherence to the surgical technique, short-term results of the Oxford phase 3 unicompartmental knee prosthesis are excellent or good in the treatment of medial compartment osteoarthritis.
20946654 Disease-specific definitions of vitamin D deficiency need to be established in autoimmune 2010 INTRODUCTION: We compared the odds of vitamin D deficiency in three chronic diseases: systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and type 2 diabetes (T2DM), adjusting for medications, demographics, and laboratory parameters, common to all three diseases. We also designed multivariate models to determine whether different factors are associated with vitamin D deficiency in different racial/ethnic groups. METHODS: We identified all patients with non-overlapping diagnoses of SLE, RA, and T2DM, with 25-hydroxyvitamin D (25OHD) levels measured between 2000 and 2009. Vitamin D deficiency was defined as 25OHD levels <20 ng/ml, based on previously established definitions. Race/ethnicity was analyzed as African-American non-Hispanic (African-American), Hispanic non-African-American (Hispanic), and Other based on self report. RESULTS: We included 3,914 patients in the final analysis: 123 SLE, 100 RA, and 3,691 T2DM. Among African-Americans the frequency of vitamin D deficiency was 59% in SLE, 47% in RA, and 67% in T2DM. Among Hispanics the frequency of vitamin D deficiency was 67% in SLE, 50% in RA, and 59% in T2DM. Compared with the SLE group, the adjusted odds ratio of vitamin D deficiency was 1.1, 95% CI (0.62, 2.1) in the RA group, and 2.0, 95% CI (1.3, 3.1) in the T2DM group. In the multivariate analysis, older age, higher serum calcium and bisphosphonate therapy were associated with a lower odds of vitamin D deficiency in all three racial/ethnic groups: 1,330 African-American, 1,257 Hispanic, and 1,100 Other. T2DM, serum creatinine, and vitamin D supplementation were associated with vitamin D deficiency in some, but not all, racial/ethnic groups. CONCLUSIONS: Vitamin D deficiency is highly prevalent in our patients with SLE, RA, and T2DM. While the odds of vitamin D deficiency are similar in RA and SLE patients in a multivariate analysis, T2DM patients have much higher odds of being vitamin D deficient. Different demographic and laboratory factors may be associated with vitamin D deficiency within different racial/ethnic groups. Therefore, disease-specific and race/ethnicity-specific definitions of vitamin D deficiency need to be established in future studies in order to define goals of vitamin D replacement in patients with autoimmune and non-autoimmune chronic diseases.
20542964 Role of IL-17 in the Th1 systemic defects in rheumatoid arthritis through selective IL-12R 2010 Aug BACKGROUND: Patients with rheumatoid arthritis (RA) have a systemic Th1 defect associated with inflammation. OBJECTIVE: To examine the hypothesis that interleukin 17 (IL-17) contributes to this defect. METHODS: IL-17 effects on Th1 markers were examined on T-bet and interferon gamma (IFNgamma) expression in peripheral blood mononuclear cells (PBMCs) from patients with RA or healthy controls (HC). Receptor specificities were determined by analysis of the Th1-specific IL-12 receptor beta2 (IL-12Rbeta2), Th17-specific IL-23R and the common IL-12Rbeta1 chain expression. Effects of IL-17 or IFNgamma on IL-6, IL-1, IL-8, matrix metalloproteinase-8 (MMP-8) were measured by real-time RT-PCR in RA synovial cells. RESULTS: RA PBMCs were less responsive to IL-12-induced IFNgamma than HC PBMCs. IL-12 hyporesponsiveness was increased by IL-17 treatment associated with a selective reduction in IL-12Rbeta2, but not IL-23R, IL-12Rbeta1 or T-bet, which was reversed with IL-17R inhibition. IL-17 inhibited IL-12Rbeta2 expression in developing Th1 cells. In RA synovial cells, IL-17 induced IL-6, IL-1, IL-8 and MMP-8, whereas IFNgamma had minimal or inhibitory effects. CONCLUSION: In RA, IL-12 hyporesponsiveness is associated with IL-17R-mediated downregulation of IL-12Rbeta2 expression. IL-17 may reinforce Th17 lineage commitment and proinflammatory and destructive effects through Th1 inhibition and positive feedback effects in RA synovial cells. Anti-inflammatory effects of IL-17/IL-17R antagonism may include the restoration of protective Th1 responses.
19713442 TREM-1 expression is increased in the synovium of rheumatoid arthritis patients and induce 2009 Nov OBJECTIVES: To investigate the expression and function of triggering receptor expressed on myeloid cells-1 (TREM-1) in the synovium of human RA patients as well as the level of soluble TREM-1 in the plasma of RA patients. METHODS: Twenty-four RA synovial samples were analysed by gene expression oligonucleotide microarrays. Expression levels of TREM-1 mRNA in murine CIA paws were determined by quantitative PCR (qPCR). TREM-1 protein expression was detected by immunohistochemistry in five RA synovial samples and two OA synovial samples. TREM-1-positive cells from five RA synovial tissues were analysed by FACS staining to determine the cell type. Activation of TREM-1 was tested in five RA synovial samples. Soluble TREM-1 was measured in serum from 32 RA patients. RESULTS: The expression of TREM-1 mRNA was found to increase 6.5-fold in RA synovial samples, whereas it was increased 132-fold in CIA paws. Increased numbers of TREM-1-positive cells were seen in RA synovium sections and these cells co-expressed CD14. Using a TREM-1-activating cross-linking antibody in RA synovial cultures, multiple pro-inflammatory cytokines were induced. The average amount of soluble TREM-1 in plasma from RA patients was found to be higher than that in plasma from healthy volunteers. CONCLUSIONS: These findings suggest that the presence of high levels of functionally active TREM-1 in RA synovium may contribute to the development or maintenance of RA, or both. Inhibiting TREM-1 activity may, therefore, have a therapeutic effect on RA. High levels of soluble TREM-1 in the plasma of RA patients compared with healthy volunteers may indicate disease activity.
20514598 [Reactivation of tuberculosis with Mycobacterium bovis infection of the oral mucosa during 2010 Jun HISTORY: A 70-year-old woman who had for five years been treated with tumour necrosis factor (TNF)-a-inhibitors for rheumatoid arthritis was admitted because of treatment-refractory oral ulcerations and persisting considerable soft-tissue swelling over the left maxilla. INVESTIGATIONS AND DIAGNOSIS: Multiple mucosal biopsies from the left maxillary sinus revealed necrotizing granulomatous inflammation suspicious of mycobacterial infection. This was subsequently confirmed in concurrent microbiological cultures and ultimately identified as Mycobacterium bovis. This species of the mycobacterium tuberculosis complex has in recent times rarely been seen in clinical practice in Germany. On further questioning the patient reported that she had been treated for "lung disease" as a schoolgirl. TREATMENT AND COURSE: The patient was isolated and quadruple therapy with isoniazide (INH), rifampin (RMP), ethambutol (EMB) and pyrazinamide (PZA) was initiated. Rapid improvement of her condition occurred within two weeks. When microbiological sub-typing using 16s-RNA sequencing had confirmed M. bovis, PZA was replaced by moxifloxacin. CONCLUSION: When investigating the cause of treatment-refractory infections and ulcerations, particularly among immunosuppressed patients, consideration should always be given to mycobacterial infections. Detailed and targeted history-taking is vital.
19534651 Interleukin-10 and articular cartilage: experimental therapeutical approaches in cartilage 2009 Aug Interleukin (IL)-10 is a well known anti-inflammatory and immunoregulatory cytokine, mainly released by, and acting on cells of the immune system such as monocytes, macrophages, T cells, NK cells, and B cells. IL-10 is also produced by a few connective tissue cell types including chondrocytes and is involved in processes such as connective tissue extracellular matrix remodelling, although it's exact function in articular cartilage remains unclear. This review article summarizes after a short insight into functions of IL-10 in the immune system most of the published literature on the role of IL-10 in articular cartilage homeostasis and disorders. A critical analysis of the present literature was undertaken leading to a survey of the significance of IL-10 in rheumatoid arthritis (RA), osteoarthritis (OA) and blood induced cartilage damage with particular focus on the direct impact of IL-10 on chondrocyte biology. IL-10 is up-regulated in RA and OA and therapeutic effects of IL-10 in experimental arthritis using several gene therapeutic approaches were reported, mainly through an immune cell mediated immunosuppression mechanism. Recently, a direct anti-inflammatory, -catabolic and -apoptotic potential of IL-10 in cartilage was described, suggesting a chondroprotective effect of IL-10, not only in RA and OA, but also in non-RA and non-systemic cartilage disorders. Chondroprotection by IL-10 may be a promising tool in arthritis therapy, as IL-10 plays a role in joint and cartilage immunoregulation and homeostasis. However, a crucial problem remains to be the optimisation of local and continuous therapeutic effective levels of IL-10 administration in the joint.
19846344 Influenza vaccine administration in rheumatoid arthritis patients under treatment with TNF 2010 Feb Twenty-eight patients with low-moderate, stable rheumatoid arthritis (RA), under treatment with tumor necrosis factor (TNF) alpha blockers, were immunized at least once with non-adjuvanted trivalent influenza vaccine during three consecutive influenza seasons. Antibodies toward A influenza antigens significantly increased and reached protective levels, still detectable 6 months after vaccination, both in RA patients and healthy controls. Response to B antigen instead was only observed from the second year for healthy controls and in the third year for patients. No significant difference in disease activity and anti-nuclear antibodies was observed as a consequence of vaccine administration, whereas T regulatory cells showed a significant increase 30 days after immunization in RA patients. This study confirms safety of influenza vaccine administration in RA patients treated with TNFalpha blockers. The cohort follow-up revealed the overcoming of poor B vaccine antigen immunogenicity via repeated vaccinations. Finally, protective antibody response was still observed 6 months after vaccination.
21106451 Novel TNF-α converting enzyme (TACE) inhibitors as potential treatment for inflammatory d 2010 Dec 15 Our research on hydantoin based TNF-α converting enzyme (TACE) inhibitors has led to an acetylene containing series that demonstrates sub-nanomolar potency (K(i)) as well as excellent activity in human whole blood. These studies led to the discovery of highly potent TACE inhibitors with good DMPK profiles.
20586704 Native albumin for targeted drug delivery. 2010 Aug IMPORTANCE IN THE FIELD: Activated cells metabolize albumin to cover their increased need for amino acids and energy. In inflamed, diseased and malignant tissue, extravasation of macromolecules into the tissue is upregulated. Drug carriers such as albumin have been used to target specifically diseased and malignant cells, resulting in higher efficacy of treatment and reduced side effects. AREAS COVERED IN THIS REVIEW: Owing to its advantageous biochemical and pharmacological properties, albumin has been regarded as an interesting candidate as a drug carrier. Covalent coupling to albumin carries drugs specifically to tumors and sites of inflammation, leading to reduced side effects as long as the native structure of albumin is unchanged. In this review, the means of coupling drugs to native albumin as well as exemplary studies for the use of albumin as drug carrier are summarized and discussed. WHAT THE READER WILL GAIN: An overview of the state-of-the-art using albumin as drug carrier for specific accumulation in tumors and inflammatory cells using the advantageous properties of native albumin is given in this review. TAKE HOME MESSAGE: Native albumin is an effective drug carrier to sites of inflammation or malignancy.
20651319 Dosing patterns and costs of tumor necrosis factor inhibitor use for rheumatoid arthritis. 2010 Aug PURPOSE: Differences in dosing patterns and costs among patients with rheumatoid arthritis (RA) treated with the tumor necrosis factor (TNF) inhibitors etanercept, adalimumab, and infliximab were analyzed on the basis of claims data. METHODS: Commercial health insurance claims data from January 2004 through December 2005 from the PharMetrics Patient-centric Database were analyzed. Adults (> or =18 years of age) with RA with a minimum of two claims for the same TNF inhibitor within a 12-month period and with at least 18 months of continuous enrollment in the database (encompassing a 6-month preindex period and a 12-month follow-up period) were included. Patients were considered treatment naive if they had no claims for a TNF inhibitor during the preindex period; continuing patients had at least one TNF-inhibitor claim during the preindex period. RESULTS: A total of 845 treatment-naive and 3783 continuing patients were included. Medication use, costs, and health care use were generally similar among the treatment groups in the preindex period for both naive and continuing patients. Among both naive and continuing patients, dose increases from the first to the last prescription were most likely to occur in the infliximab group (26% and 24%, respectively) compared with the adalimumab (10% and 9%) and etanercept (1% and 3%) groups. Etanercept was associated with the lowest and infliximab with the highest total anti-TNF therapy costs. Anti-TNF-related costs were higher among patients with a high index dose, a dose increase, or both during the follow-up period than among those without. CONCLUSION: Dose increases with TNF inhibitors commonly occurred in RA patients in the clinical setting and were associated with greater costs of anti-TNF therapy.
19815670 Investigating the role of the interleukin-23/-17A axis in rheumatoid arthritis. 2009 Dec OBJECTIVE: IL-23 is a pro-inflammatory cytokine proposed to be central to the development of autoimmune disease. We investigated whether IL-23, together with the downstream mediator IL-17A, was present and functional in RA in humans. METHODS: RA synovial cells were cultured in the presence or absence of antibodies directed against IL-23p19 or -23R and -17. IL-23, -12, -17, and their receptors, and IL-6, -1beta and TNF-alpha were measured by ELISA and/or PCR. RESULTS: Small amounts of cell-associated IL-23 (median 110 pg/ml) were detected in RA synovial cultures, and found to be functional as IL-23R blockade resulting in a significant inhibition of TNF-alpha (57%), IL-1beta (51%) and IL-6 (30%). However, there was a considerable variability between individual patient samples, and anti-IL-23p19 was found to be considerably less effective. IL-17A protein was detected in approximately 40% of the supernatants and IL-17A blockade, in IL-17A-producing cultures, resulted in a small but significant inhibition of TNF-alpha (38%), IL-1beta (23%) and IL-6 (22%). Addition of recombinant IL-23 to cultures had a variable effect on the spontaneous production of endogenous IL-17A with enhancement observed in some but not all cultures, suggesting that either the low levels of endogenous IL-23 are sufficient to support cytokine production and/or that the relevant Th17 cells were not present. CONCLUSIONS: These results suggest that although IL-23 may have pathogenic activity in a proportion of patients with late-stage RA, it is not abundantly produced in this inflammatory tissue, nor does it have a dominant role in all patient tissues analysed.
19883500 Adiponectin may contribute to synovitis and joint destruction in rheumatoid arthritis by s 2009 INTRODUCTION: The role of adiponectin in the pathogenesis of arthritis is still controversial. This study was performed to examine whether adiponectin is involved in joint inflammation and destruction in rheumatoid arthritis (RA) in relation to the expression of vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMPs). METHODS: Synovial cells from RA patients were treated with adiponectin or interleukin (IL)-1beta for 24 hours. The culture supernatant was collected and analyzed for the levels of IL-6, IL-8, prostaglandin E2 (PGE2), VEGF, and MMPs by enzyme-linked immunosorbent assay. The levels of adiponectin, VEGF, MMP-1, and MMP-13 in the joint fluids from 30 RA or osteoarthritis (OA) patients were also measured. RESULTS: Adiponectin at the concentration of 10 microg/mL stimulated the production of IL-6, IL-8, and PGE2 in RA fibroblast-like synoviocytes (FLSs), although the level of these was much lower than with 1 ng/mL IL-1beta. However, adiponectin stimulated the production of VEGF, MMP-1, and MMP-13 at the same level as IL-1beta. In addition, the level of adiponectin and MMP-1 in the joint fluid of RA patients was significantly higher than in OA patients. Adiponectin was positively correlated with VEGF in RA patients but not in OA patients, while the level of MMPs in joint fluid was not correlated with adiponectin in either RA or OA patients. CONCLUSIONS: Adiponectin may play a significant role in the pathogenesis of RA by stimulating the production of VEGF and MMPs in FLSs, leading to joint inflammation and destruction, respectively.
19900268 Altered peptide ligands inhibit arthritis induced by glucose-6-phosphate isomerase peptide 2009 INTRODUCTION: Immunosuppressants, including anti-TNFalpha antibodies, have remarkable effects in rheumatoid arthritis; however, they increase infectious events. The present study was designed to examine the effects and immunological change of action of altered peptide ligands (APLs) on glucose-6-phosphate isomerase (GPI) peptide-induced arthritis. METHODS: DBA/1 mice were immunized with hGPI325-339, and cells of draining lymph node (DLN) were stimulated with hGPI325-339 to investigate the T-cell receptor (TCR) repertoire of antigen-specific CD4+ T cells by flow cytometry. Twenty types of APLs with one amino acid substitution at a TCR contact site of hGPI325-339 were synthesized. CD4+ T cells primed with human GPI and antigen-presenting cells were co-cultured with each APL and cytokine production was measured by ELISA to identify antagonistic APLs. Antagonistic APLs were co-immunized with hGPI325-339 to investigate whether arthritis could be antigen-specifically inhibited by APL. After co-immunization, DLN cells were stimulated with hGPI325-339 or APL to investigate Th17 and regulatory T-cell population by flow cytometry, and anti-mouse GPI antibodies were measured by ELISA. RESULTS: Human GPI325-339-specific Th17 cells showed predominant usage of TCRVbeta8.1 8.2. Among the 20 synthesized APLs, four (APL 6; N329S, APL 7; N329T, APL 12; G332A, APL 13; G332V) significantly reduced IL-17 production by CD4+ T cells in the presence of hGPI325-339. Co-immunization with each antagonistic APL markedly prevented the development of arthritis, especially APL 13 (G332V). Although co-immunization with APL did not affect the population of Th17 and regulatory T cells, the titers of anti-mouse GPI antibodies in mice co-immunized with APL were significantly lower than in those without APL. CONCLUSIONS: We prepared antagonistic APLs that antigen-specifically inhibited the development of experimental arthritis. Understanding the inhibitory mechanisms of APLs may pave the way for the development of novel therapies for arthritis induced by autoimmune responses to ubiquitous antigens.
20564001 Impaired activation-induced cell death promotes spontaneous arthritis in antigen (cartilag 2010 Oct OBJECTIVE: To investigate whether genetic preponderance of a T cell receptor (TCR) recognizing an arthritogenic peptide of human cartilage proteoglycan (PG) is sufficient for development of arthritis. METHODS: We performed a longitudinal study using BALB/c mice expressing a TCR that recognizes the arthritogenic ATEGRVRVNSAYQDK peptide of human cartilage PG. PG-specific TCR-transgenic (PG-TCR-Tg) mice were inspected weekly for peripheral arthritis until 12 months of age. Peripheral joints were examined histologically, and T cell responses, T cell activation markers, serum cytokines, and autoantibodies were measured. Apoptosis and signaling studies were performed in vitro on T cells from aged PG-TCR-Tg mice. RESULTS: Spontaneous arthritis developed as early as 5-6 months of age, and the incidence increased to 40-50% by 12 months of age. Progressive inflammation began with cartilage and bone erosions in the interphalangeal joints, and later expanded to the proximal joints of the front and hind paws. Spontaneous arthritis was associated with a high proportion of activated CD4+ T cells, enhanced interferon-γ and interleukin-17 (IL-17) production, and elevated levels of serum autoantibodies. PG-TCR-Tg mice lacking IL-4 developed arthritis earlier and at a higher incidence than IL-4-sufficient mice. Antigen-specific activation-induced cell death was diminished in vitro in CD4+ T cells of PG-TCR-Tg mice with spontaneous arthritis, especially in those lacking IL-4. CONCLUSION: The presence of CD4+ T cells expressing a TCR specific for an arthritogenic PG epitope is sufficient to trigger spontaneous autoimmune inflammation in the joints of BALB/c mice. IL-4 appears to be a negative regulator of this disease, through attenuation of activation-induced cell death.
20020138 Adult-onset Still's disease. 2010 May Adult-onset Still's disease (AOSD) is a rare systemic inflammatory disorder characterised by high spiking fever, an evanescent salmon pink rash and arthritis, frequently accompanied by sore throat, myalgias, lymphadenopathies, splenomegaly and neutrophilic leukocytosis. Aetiology is still unknown, however, it seems that an important role is played by various infectious agents, which would act as triggers in genetically predisposed hosts. Diagnosis is a clinical one and may be lengthy because it requires exclusion of infectious neoplasms, including malignant lymphomas and leukaemias, and other autoimmune diseases. Different diagnostic or classification criteria have been proposed, but not definitely accepted. There are no specific laboratory tests for AOSD, but they reflect the systemic inflammation: the ESR is consistently high, while the rheumatoid factors and antinuclear antibodies are negative. High serum ferritin levels associated with a low fraction of its glycosylated component are assessed as useful diagnostic and disease activity markers. The clinical course can be divided into three main patterns with different prognoses: self-limited or monophasic, intermittent or polycyclic systemic and chronic articular pattern. Therapy includes non-steroidal anti-inflammatory drugs, corticosteroids and disease modifying anti-rheumatic drugs: biological agents have recently been introduced and they seem to be very promising not only for the treatment but also for understanding the pathogenic mechanisms underlying the disease.