Search for: rheumatoid arthritis methotrexate autoimmune disease biomarker gene expression GWAS HLA genes non-HLA genes
| ID | PMID | Title | PublicationDate | abstract |
|---|---|---|---|---|
| 16883066 | Regulation of annexin I in rheumatoid synovial cells by glucocorticoids and interleukin-1. | 2006 | The glucocorticoid (GC)-induced antiinflammatory molecule annexin I is expressed in leukocytes and has antiinflammatory effects in animal models of arthritis, but the expression of annexin I in rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLS) is unknown. We report the constitutive and dexamethasone (DEX)-inducible expression of annexin I in RA FLS. DEX increased FLS annexin I protein translocation and mRNA expression. Interleukin (IL)-1beta also induced annexin I translocation and mRNA but also increased intracellular protein. DEX and IL-1 had additive effects on annexin I mRNA, but DEX inhibited the inducing effect of IL-1beta on cell surface annexin I. These results indicate that glucocorticoids and IL-1beta upregulate the synthesis and translocation of annexin I in RA FLS, but interdependent signalling pathways are involved. | |
| 16924705 | [Experiment treatment of collagen-induced arthritis in rats with recombinant plasmid conta | 2006 Jul | OBJECTIVE: To investigate the therapeutical effect of recombinant plasmid containing vasoactive intestinal peptide gene (pcDNA3.1+/VIP) on collagen-induced arthritis (CIA) in rats. METHODS: The experimental arthritis was induced by intradermal injection of bovine type II collagen emulsified in Freund's adjuvants in male SD rats. The rats then were given intra-articular injection with recombinant plasmid (pcDNA3.1+/VIP). The levels of serum TNF-alpha, IL-4 and IL-2 were detected by Avidin-Biotin Peroxdase Complex-enzyme-linked immunosorbent assay (ABC-ELISA) and the pathological changes in the joint of rats were observed. RESULT: Histological examination showed massive inflammatory infiltration in the joint with destruction of bone and cartilage, while the severity of pathological changes in synovia of VIP-treated rats was markedly reduced. Compared with normal group, the serum TNF-alpha, IL-2 levels of CIA rats were significantly increased (P <0.05) and IL-4 level was decreased (P<0.05). Compared with control and pcDNA3.1+ -treated CIA rats, serum TNF-alpha and IL-2 levels of pcDNA3.1+/VIP-treated rats were decreased and IL-4 level was increased (P<0.05). CONCLUSION: Recombinant plasmid containing vasoactive intestinal peptide gene (pcDNA3.1+/VIP) can reduce the clinical and histological severity of established CIA and it might be a promising candidate for treatment of rheumatoid arthritis. | |
| 17430797 | [Biological therapy of arthritis and systemic autoimmune diseases]. | 2007 Apr 8 | The concept of biological therapy arises from the specific targeting of a factor, e.g. a cytokine, involved in the inflammatory cascade. Thus, biologicals disrupt the complex network of autoimmune-inflammatory events. Today, rheumatoid arthritis is a prototype disease in this context as most compounds have been tried in this disease. Recently, biological therapy has been introduced to the treatment of other diseases including various forms of arthritis, such as ankylosing spondylitis and psoriatic arthritis, as well as systemic autoimmune disorders, such as systemic lupus erythematosus, scleroderma, inflammatory myopathies and Sjogren's syndrome. Anti-tumor necrosis factor-alpha (TNF-alpha) agents play a central role in biological therapy as these agents have been successfully tried in most of these diseases. When seeking for specific targets for biologicals, pathogenic factors of the disease, such as Th1 or Th2 type responses, should be evaluated. Some mostly T-cell mediated diseases, such as rheumatoid arthritis, ankylosing spondylitis, psoriasis, polymyositis, polyarticular juvenile arthritis respond well to anti-TNF agents and T cell targeting, while others, such as lupus, Sjogren's syndrome, dermatomyositis may rather respond to anti-B cell biologicals. In this review, authors discuss the most recent advances in the biological therapy of arthritis and systemic autoimmune diseases including issues of efficacy and safety. | |
| 17687101 | Fatal pulmonary Mycobacterium xenopi in a patient with rheumatoid arthritis receiving etan | 2007 Aug | Mycobacterium xenopi is a water-related mycobacterium with low pathogenicity in humans. Little is known about the association between anti-tumour necrosis factor (TNF)alpha and non-tuberculous mycobacterial infections. The case history is presented of fatal M xenopi infection in a patient receiving anti-TNFalpha treatment. | |
| 18576295 | A randomized, double-blind, multicenter, controlled clinical trial of chicken type II coll | 2008 Jul 15 | OBJECTIVE: To assess the efficacy and safety of chicken type II collagen (CCII) in rheumatoid arthritis (RA) compared with methotrexate (MTX). METHODS: We conducted a prospective, 24-week, followup, multicenter, double-blind, controlled study of CCII (0.1 mg/day) versus MTX (10 mg/week) in patients with active RA. Clinical assessments were performed at screening and at 12, 18, and 24 weeks of treatment. RESULTS: A total of 236 RA patients were included; 211 patients (89.4%) completed the 24-week followup. In both groups there was a decrease in pain, morning stiffness, tender joint count, swollen joint count, Health Assessment Questionnaire score, and investigator and patient assessment of function; all differences were statistically significant. In the MTX group, erythrocyte sedimentation rate and C-reactive protein level decreased. Rheumatoid factor did not change in either group. At 24 weeks, 68.57% of patients in the CCII group and 83.02% in the MTX group met the American College of Rheumatology 20% improvement criteria (ACR20), and 40.95% and 57.54%, respectively, met the ACR50 criteria. The ACR20 and ACR50 response rates in the CCII group were lower than those in the MTX group, and this difference was statistically significant (P < 0.05). Gastrointestinal symptoms were common in both groups. There were fewer and milder side effects in the CCII group than the MTX group. The difference in incidence of adverse events between the 2 groups was statistically significant (P < 0.05). CONCLUSION: CCII is effective in the treatment of RA. CCII is well tolerated, and the incidence of adverse events of CCII is lower than that of MTX. | |
| 18050209 | Fine specificity of the anti-citrullinated protein antibody response is influenced by the | 2007 Dec | OBJECTIVE: In classic studies on the genetic background of antibody production, the major histocompatibility complex (MHC) has been shown to act as the most prominent immune response gene that controls the magnitude and the specificity of antibody production. The strongest genetic risk factor for rheumatoid arthritis (RA), the human MHC HLA-DRB1 shared epitope (SE) alleles, predisposes for antibodies against citrullinated proteins (ACPAs). ACPA levels are higher in SE-positive patients with RA than in SE-negative patients with RA. The aim of the present study was to determine whether SE influences not only the magnitude but also the specificity of the ACPA response. METHODS: In 2 cohorts of anti-citrullinated peptide 2-positive patients with RA, one from a study of recent-onset arthritis (n = 206) and the other from a treatment strategy study (n = 141), serum antibodies against a citrullinated peptide derived from vimentin (cVim) and antibodies against a citrullinated fibrinogen peptide (cFibr) were determined by enzyme-linked immunosorbent assay. HLA-DRB1 genotyping was performed. RESULTS: In the first cohort, SE alleles were significantly associated with the presence of antibodies against cVim (odds ratio [OR] 4.95, 95% confidence interval [95% CI] 1.87-15.3) and were not significantly associated with the presence of antibodies against cFibr (OR 1.71, 95% CI 0.70-4.14). These results were replicated in the second cohort (OR 5.05, 95% CI 1.92-13.6 and OR 1.19, 95% CI 0.30-3.97, respectively). CONCLUSION: In 2 cohorts of ACPA-positive patients with RA, SE alleles predisposed for the development of antibodies against cVim but not for the development of antibodies against cFibr. These data indicate that SE alleles act as "classic" immune response genes in the ACPA response, because they influence both the magnitude and the specificity of this RA-specific antibody response. | |
| 19055696 | The therapeutic effect of vasoactive intestinal peptide on experimental arthritis is assoc | 2008 Dec | Vasoactive intestinal peptide (VIP) has been found to act as a potent anti-inflammatory factor through regulating the production of both anti- and pro-inflammatory mediators and promoting Th2-type responses. In this study, we used Chicken collagen II-induced experimental arthritis (CIA) model in Wistar rats to investigate the potential effects of VIP on rheumatoid arthritis. Our results showed that in vivo treatment of CIA-induced rats with VIP had great protective benefit at both clinical and histological levels. Disease suppression was associated with the inhibition of T cells proliferation, shifting of the immune response toward a Th2-type response and expanded CD4(+)CD25(+) Treg in the periphery, which inhibited autoreactive T cell activation/expansion. In conclusion, the study provides evidence that VIP had great protective effect on CIA through its inhibition actions on pathogenic T cells. | |
| 18272669 | Do changes in prescription practice in patients with rheumatoid arthritis treated with bio | 2008 Jul | BACKGROUND: Prescription practice for tumour necrosis factor alpha (TNFalpha) inhibitors has changed towards treating patients with lower disease activity. OBJECTIVE: To determine the trend in treatment response in cohorts of patients with rheumatoid arthritis who started TNFalpha inhibitor treatment between 2000 and 2005. METHODS: 1813 patients with RA starting treatment with biological agents in 2000-5 were registered prospectively in the nationwide DANBIO Registry. Baseline disease activity and 12 months' treatment responses were determined in cohorts based on start year (2000/1; 2002; 2003; 2004; 2005). RESULTS: Despite decreasing baseline disease activity from the 2000/2001 cohort to 2005 cohort (28-joint count Disease Activity Score (DAS28): from 5.9 to 5.3 (p<0.001)), the 12 months' DAS improvement increased from 1.8 units (2000/2001 cohort) to 2.2 units (2005 cohort) (p<0.001). The fraction with good EULAR response increased from 28% (2000/2001 cohort) to 50% (2005 cohort); the fraction with no response decreased from 29% (2000/2001 cohort) to 16% (2005 cohort). ACR20/50/70 response rates increased from 53%/31%/13% (2000/2001 cohort) to 69%/51%/30% (2005 cohort). After correction for withdrawals, treatment responses were lower, but patterns unchanged. One-year drug survival was for the 2000/2001 cohort: 73%, 2002: 62%, 2003: 67%, 2004: 70%, 2005: 69%. CONCLUSION: From 2000 to 2005, significantly improved treatment responses to TNF inhibitors were seen in clinical practice despite decreasing baseline disease activity levels. This lends support to the less stringent prescription practice towards treating patients with lower disease activity that has been observed in several countries. | |
| 17278015 | Efficacy and safety of iguratimod compared with placebo and salazosulfapyridine in active | 2007 | We conducted a 28-week, randomized, double-blind, parallel-group study of iguratimod in 376 Japanese patients with active rheumatoid arthritis to compare the efficacy and safety of the drug with those of placebo and salazosulfapyridine. In the American College of Rheumatology (ACR) 20 response rate, iguratimod was superior to placebo (53.8% versus 17.2%; Fisher's exact test, P < 0.001) and was not inferior to salazosulfapyridine (63.1% versus 57.7%, 95% confidence interval for the rate difference, -7.9% to 18.7%). Iguratimod began exhibiting its therapeutic effect within 8 weeks after the initiation of treatment and was effective even in patients who had a poor response to previous treatment with disease-modifying antirheumatic drugs. No statistically significant difference was noted in the incidence of adverse reactions between iguratimod and salazosulfapyridine. The study results suggest that iguratimod could become a new option for the treatment of rheumatoid arthritis. | |
| 16963793 | Methotrexate in rheumatoid arthritis. | 2006 Jul | A variety of disease-modifying antirheumatic drugs (DMARDs) are available to control the clinical activity of rheumatoid arthritis (RA). Methotrexate (MTX), an analogue of folic acid and of aminopterin, is the most commonly used DMARD and is now prescribed worldwide to at least 500,000 patients with RA. The mechanism by which MTX used at a low dose modulates inflammation in RA is still unknown. Monitoring of the therapy in terms of MTX concentration in patients with RA seems not to have a significant influence on the effectiveness of the treatment. Two meta-analyses showed that MTX has one of the best efficacy/toxicity ratios. It should be the first DMARD used in the majority of patients with RA at this time. However, a significant number of patients treated only with MTX fail to achieve optimal disease control, so there are many combinations of DMARD regimes. It is hoped that more aggressive use of conventional DMARDs and biological agents will result in less disability and a higher proportion of patients achieving remission. The therapy of RA is a dynamic process and requires maintaining a delicate balance between benefits and risks. Even with the newer biological agents, MTX continues to serve as a reference point and there is still a role for MTX in the treatment of RA patients. | |
| 18163493 | Arthritogenic antibodies specific for a major type II collagen triple-helical epitope bind | 2008 Jan | OBJECTIVE: To investigate the significance and pathogenic potential of a highly conserved major type II collagen triple-helical epitope-specific antibody (U1; amino acids 494-504) in vivo and in vitro in patients with early rheumatoid arthritis (RA) and in experimental animal models of collagen-induced arthritis (CIA). METHODS: U1-specific antibodies in sera from patients with early RA (with or without joint erosions) were analyzed. Disease progression in the CIA models in mice and rats with anti-U1 antibodies was compared. The pathogenicity of binding of monoclonal antibodies (mAb) UL1 and CIIF4 to the U1 epitope and the F4 epitope (aa 926-936), respectively, was compared in vivo and on chondrocyte cultures and preformed cartilage in vitro, using Fourier transform infrared microspectroscopy analysis. In addition, UL1-induced proteoglycan depletion in vivo in the presence and absence of the complement factor C5 was analyzed. RESULTS: Increased levels of U1 antibodies were observed in patients with early RA, especially in association with joint erosions. A significant correlation of U1-specific antibodies with disease progression was found in rats and mice with CIA. UL1 mAb induced, whereas CIIF4 mAb inhibited, the progression of arthritis. Similarly, UL1, but not CIIF4, impaired matrix synthesis on chondrocyte cultures and adversely affected preformed cartilage. Furthermore, UL1 induced significant proteoglycan depletion in vivo 3 days after injection, even in the absence of C5. CONCLUSION: Antibody epitope specificity contributes significantly to the development of arthritis, and the early pathogenic events operate independent of inflammation both in vitro and in vivo. | |
| 16978150 | Plasmid DNA acquires immunogenicity on exposure to singlet oxygen. | 2006 Aug | In the present study, the effect of singlet oxygen (1O2) (generated by ultraviolet (UV) irradiation of methylene blue) on plasmid DNA has been analyzed by UV spectroscopy, fluorescence spectroscopy, and S1 nuclease digestibility. Both native and 1O2-modified plasmid DNA were treated with a number of restriction enzymes to map out the sites damaged by 1O2. It was also observed that, on exposure to 1O2, native plasmid DNA that is non-immunogenic acquired the ability to elicit an immune response in experimental animals. However, the induced antibodies exhibited appreciable cross reactivity with various polynucleotides and nucleic acids. The data indicate that the antibodies, though cross-reactive, preferentially bind 1O2-modified epitopes on plasmid DNA. Gel retardation assay further substantiated the enhanced recognition of 1O2-modified plasmid DNA over the native form. The antibodies developed were then subjected to competition ELISA with sera from various diseases such as systemic lupus erythematosus, rheumatoid arthritis, and cancer. These results suggest that upon exposure of DNA to 1O2, neo-epitopes are generated, which may be one of the factors for the induction of circulating autoantibodies in the three diseases. | |
| 17044206 | Tuberculosis in patients receiving anti-TNF agents despite chemoprophylaxis. | 2006 Oct | SETTING: A major concern surrounding the use of tumor necrosis factor-alpha (TNF-alpha) inhibitors is their potential to increase the risk of opportunistic infections, particularly tuberculosis (TB). OBJECTIVE: To estimate the incidence of active TB in patients with rheumatic diseases receiving anti-TNF drug therapy and to evaluate the effectiveness of an antituberculosis chemoprophylaxis regimen. DESIGN: Retrospective study of the files of 613 patients with rheumatic diseases who had received anti-TNF agent (etanercept, infliximab and adalimumab) therapy from July 2000 to June 2004 at the Aristotle University of Thessaloniki, Greece. All patients had a tuberculin skin test (TST) and a postero-anterior chest radiograph (CXR) prior to anti-TNF therapy. When indicated (TST > or =10 mm and/or fibrotic lesions on CXR), treatment for latent TB was established (6 months isoniazid [INH] or 3 months INH and rifampicin [RMP]). Anti-TNF agent therapy was started again 2 months later. RESULTS: Of 45 patients who fulfilled the criteria for chemoprophylaxis, only 36 were treated correctly. Eleven patients developed active TB 2-35 months after the beginning of anti-TNF therapy. Six patients developed pulmonary and five extra-pulmonary TB. Eight of these had received infliximab and three adalimumab. CONCLUSION: The incidence of active TB in this study population was estimated at 449 cases per 100,00 population annually. Anti-tuberculosis chemoprophylaxis was only of partial preventive success in these patients. | |
| 17932559 | Association of STAT4 with rheumatoid arthritis in the Korean population. | 2007 Sep | A recent study in the North American White population has documented the association of a common STAT4 haplotype (tagged by rs7574865) with risk for rheumatoid arthritis (RA) and systemic lupus erythematosus. To replicate this finding in the Korean population, we performed a case-control association study. We genotyped 67 single nucleotide polymorphisms (SNPs) within the STAT1 and STAT4 regions in 1123 Korean patients with RA and 1008 ethnicity-matched controls. The most significant four risk SNPs (rs11889341, rs7574865, rs8179673, and rs10181656 located within the third intron of STAT4) among 67 SNPs are identical with those in the North American study. All four SNPs have modest risk for RA susceptibility (odds ratio 1.21-1.27). A common haplotype defined by these markers (TTCG) carries significant risk for RA in Koreans [34 percent versus 28 percent, P=0.0027, OR (95 percent CI)=1.33 (1.10-1.60)]. By logistic regression analysis, this haplotype is an independent risk factor in addition to the classical shared epitope alleles at the HLA-DRB1 locus. There were no significant associations with age of disease onset, radiographic progression, or serologic status using either allelic or haplotypic analysis. Unlike several other risk genes for RA such as PTPN22, PADI4, and FCRL3, a haplotype of the STAT4 gene shows consistent association with RA susceptibility across Whites and Asians, suggesting that this risk haplotype predates the divergence of the major racial groups. | |
| 17604289 | Evidence for an influence of chemokine ligand 3-like 1 (CCL3L1) gene copy number on suscep | 2008 Mar | OBJECTIVE: There is increasing evidence that gene copy-number variation influences phenotypic variation. Chemokine ligand 3-like 1 (CCL3L1) is encoded by a variable copy-number gene, and binds to several pro-inflammatory cytokine receptors, including chemokine receptor 5 (CCR5). Considering lymphocyte recruitment by beta-chemokines is a feature of autoimmunity, and that the CCR5Delta32 variant is associated with protection to rheumatoid arthritis (RA), we hypothesised that CCL3L1 copy-number influences susceptibility to RA and type 1 diabetes (T1D). METHODS: We measured CCL3L1 copy-number in 1136 RA cases from New Zealand (NZ) and the UK, 252 NZ T1D cases and a total of 1470 controls. All subjects were ancestrally Caucasian. RESULTS: A copy-number higher than 2 (the most common copy number) was a risk factor for RA in the NZ cohort (odds ratio (OR) 1.34, 95% CI 1.08-1.66, p = 0.009) but not the smaller UK RA cohort (OR 1.09, 95% CI 0.75-1.60, p = 0.643). There was evidence for association in the T1D cohort (OR 1.46, 95% CI 0.98-2.20, p = 0.064) and in the combined RA/T1D cohort (OR 1.30, 95% CI 1.00-1.54, p = 0.003). Genetic interaction between CCL3L1 dosage and CCR5 genotype was found; the increased genetic risk conferred by higher CCL3L1 copy-number was ablated by a dysfunctional CCR5 (CCR5Delta32). CONCLUSIONS: These data suggest that increased CCL3L1 expression may enhance inflammatory responses and increase the chance of autoimmune disease. Genetic interaction data were consistent with a biologically plausible model; CCR5Delta32 protects against RA and T1D by blocking signalling through the CCR5 pathway, mitigating the pro-inflammatory effects of excess CCL3L1. | |
| 18847495 | Toll-like receptor homolog RP105 modulates the antigen-presenting cell function and regula | 2008 | INTRODUCTION: RP105 is a Toll-like receptor homolog expressed on B cells, dendritic cells (DCs), and macrophages. We investigated the role of RP105 in the development of collagen-induced arthritis (CIA). METHODS: CIA was induced in RP105-deficient DBA/1 mice and the incidence and arthritis index were analyzed. The cytokine production by spleen cells was determined. The functions of the DCs and regulatory T cells (Tregs) from RP105-deficient or control mice were determined by adding these cells to the lymph node cell culture. Arthritis was also induced by incomplete Freund's adjuvant (IFA) plus collagen or by injecting anti-collagen antibody and lipopolysaccharide. RESULTS: RP105-deficient mice showed accelerated onset of arthritis and increased severity. Interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha production by spleen cells from RP105-deficient mice was increased in comparison with that from wild-type mice. The DCs from RP105-deficient mice induced more IFN-gamma production, whereas Tregs from those mice showed less inhibitory effect against IFN-gamma production. RP105-deficient mice also showed more severe arthritis induced by collagen with IFA. CONCLUSIONS: These results indicate that RP105 regulates the antigen-presenting cell function and Treg development, which induced the attenuation of the cell-mediated immune responses and, as a result, suppressed the development of CIA. | |
| 17075829 | Activation of nitric oxide signaling by the rheumatoid arthritis shared epitope. | 2006 Nov | OBJECTIVE: Susceptibility to rheumatoid arthritis (RA) is closely associated with HLA-DRB1 alleles encoding a shared epitope (SE) in positions 70-74 of the HLA-DRbeta chain. The mechanistic basis for this association is unknown. Given the proposed pathogenic role of nitric oxide (NO) in RA, this study was undertaken to examine whether the SE can trigger NO signaling events. METHODS: The intracellular levels of NO were measured with the fluorescent NO probe 4,5-diaminofluorescein diacetate and by the 2,3-diaminonaphthalene method. NO synthase activity was determined by measuring the rate of conversion of radioactive arginine to citrulline. Levels of cGMP were measured with a commercial enzyme-linked immunosorbent assay, and the cytolytic activity of T cells was measured using a standard (51)Cr release assay. RESULTS: Lymphoblastoid B cell lines carrying SE-positive HLA-DR alleles displayed a higher rate of spontaneous NO production compared with SE-negative cells. L cell transfectants expressing SE-positive DR molecules on their surface also generated higher levels of NO. Tetrameric HLA-DR molecules containing a DRbeta-chain encoded by the SE-positive DRB1*0401 allele stimulated fibroblast cells to produce higher levels of NO compared with cells stimulated with a control HLA-DR tetramer. Multimeric hepatitis B core proteins engineered to express region 65-79 encoded by the DRB1*0401 allele, but not the same region encoded by the control allele DRB1*0402, stimulated NO production in fibroblasts. Similarly, synthetic 15-mer peptides corresponding to the region 65-79 encoded by SE-positive alleles triggered increased NO levels when incubated with class II major histocompatibility complex-negative cells. The signaling pathway was found to involve NO synthase activation, followed by increased production of cGMP. SE-triggered increased NO levels inhibited cytolytic elimination of target cells. CONCLUSION: The SE can trigger NO-mediated signaling events in opposite cells, and may thereby contribute to RA pathogenesis. | |
| 17947714 | The rheumatoid arthritis shared epitope triggers innate immune signaling via cell surface | 2007 Nov 1 | The shared epitope (SE), carried by the vast majority of rheumatoid arthritis patients, is a 5-aa sequence motif in the third allelic hypervariable region of the HLA-DRbeta chain. We have recently demonstrated that the SE acts as an allele-specific ligand that triggers NO-mediated pro-oxidative signaling in opposite cells. The identity of the cell surface molecule that interacts with the SE is unknown. Using affinity chromatography purification, cell-binding assays, surface plasmon resonance, and time-resolved fluorescence resonance energy transfer techniques, we have identified cell surface calreticulin (CRT) as the SE-binding molecule. SE-triggered signaling could be blocked by anti-CRT Abs or Abs against CD91 and by CRT-specific antisense or small-interfering RNA oligonucleotides. Embryonic fibroblasts from crt(-/-) or CD91-deficient mice failed to transduce SE-triggered signals. Exogenously added soluble CRT attached to the cell surface and restored SE-triggered signaling responsiveness in crt(-/-) cells. These data indicate that cell surface CRT, a known innate immunity receptor, which has been previously proposed as a culprit in autoimmunity, plays a critical role in SE-triggered signal transduction. | |
| 18710572 | Circulating immune complexes contain citrullinated fibrinogen in rheumatoid arthritis. | 2008 | INTRODUCTION: There is increasing evidence that autoantibodies and immune complexes (ICs) contribute to synovitis in rheumatoid arthritis (RA), yet the autoantigens incorporated in ICs in RA remain incompletely characterised. METHODS: We used the C1q protein to capture ICs from plasma derived from human RA and control patients. Antibodies specific for immunoglobulin were used to detect ICs, and fibrinogen antibodies were used to detect fibrinogen-containing ICs. RA and control plasma were separated by liquid chromatography, and fractions then characterised by ELISA, immunoblotting and mass spectrometry. Immunohistochemical staining was performed on rheumatoid synovial tissue. RESULTS: C1q-immunoassays demonstrated increased levels of IgG (p = 0.01) and IgM (p = 0.0002) ICs in plasma derived from RA patients possessing anti-cyclic citrullinated peptide (CCP+) autoantibodies as compared with healthy controls. About one-half of the anti-CCP+ RA possessed circulating ICs containing fibrinogen (p = 0.0004). Fractionation of whole RA plasma revealed citrullinated fibrinogen in the high molecular weight fractions that contained ICs. Positive correlations were observed between fibrinogen-containing ICs and anti-citrullinated fibrinogen autoantibodies, anti-CCP antibody, rheumatoid factor and certain clinical characteristics. Immunohistochemical staining demonstrated co-localisation of fibrinogen, immunoglobulin and complement component C3 in RA pannus tissue. Mass spectrometry analysis of immune complexes immunoprecipitated from RA pannus tissue lysates demonstrated the presence of citrullinated fibrinogen. CONCLUSION: Circulating ICs containing citrullinated fibrinogen are present in one-half of anti-CCP+ RA patients, and these ICs co-localise with C3 in the rheumatoid synovium suggesting that they contribute to synovitis in a subset of RA patients. | |
| 19067101 | Adalimumab response in patients with early versus established rheumatoid arthritis: DE019 | 2009 Apr | In recent years, there has been a shift in the therapeutic approach to rheumatoid arthritis (RA), with emphasis on early therapy. The DE019 trial demonstrated adalimumab efficacy in patients with RA. This subanalysis compares response to adalimumab based on clinical, functional, and radiographic outcomes in patients with early versus established RA. Patients enrolled in the DE019 trial were divided into two groups based on disease duration ( |