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ID PMID Title PublicationDate abstract
22364131 Excess cardiovascular risk in inflammatory rheumatic diseases: pathophysiology and targete 2012 The article reviews the evidence and extent of the excess cardiovascular risk in patients with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) and ankylosing spondylitis. RA entails nearly twice as high a standardized mortality ratio and is considered an equivalent of type 2 diabetes with regard to cardiovascular risk. The associated excess cardiovascular risk can only partly be explained by traditional risk factors, and the underlying inflammation is crucially involved in the pathogenesis. Data obtained from patients with early RA suggest that serum triglycerides, a proxy of disease activity as markers of systemic inflammation, impaired function of apolipoprotein A-I and HDL particles, and mediating hypertension are determinants of the excess cardiovascular risk. These changes seem to be preceded by a lowering of total cholesterol and are followed in the course of the disease by immune processes typically illustrated by positivity of rheumatoid factor. Evidence is available to postulate the notion that reduced plasma lipoprotein- associated phospholipaseA2 mass or activity, mediated by diminished hydrolysis of VLDL triglycerides and of Lp(a) phospholipids, may induce reduction or altered composition of HDL particles and apoA-I dysfunction which, along with elevated plasma triglycerides, initiate and contribute to chronic inflammation. Lifestyle modification, traditional non-steroidal anti-inflammatory drugs and cyclo-oxygenase-2 inhibitors, low-dose corticosteroids, statins, tumor-necrosis-α inhibitors and, particularly, the immunosuppressive methotrexate, all have potential beneficial effects in eliciting a reduction in disease activity and cardiovascular risk. Adherence to the recent EULAR recommendations is a key in the prevention and management of cardiovascular risk among patients with rheumatic diseases.
22494514 Intimal lining layer macrophages but not synovial sublining macrophages display an IL-10 p 2012 Apr 11 INTRODUCTION: Synovial tissue macrophages play a key role in chronic inflammatory arthritis, but the contribution of different macrophage subsets in this process remains largely unknown. The main in vitro polarized macrophage subsets are classically (M1) and alternatively (M2) activated macrophages, the latter comprising interleukin (IL)-4 and IL-10 polarized cells. Here, we aimed to evaluate the polarization status of synovial macrophages in spondyloarthritis (SpA) and rheumatoid arthritis (RA). METHODS: Expression of polarization markers on synovial macrophages, peripheral blood monocytes, and in vitro polarized monocyte-derived macrophages from SpA versus RA patients was assessed by immunohistochemistry and flow cytometry, respectively. The polarization status of the intimal lining layer and the synovial sublining macrophages was assessed by double immunofluorescence staining. RESULTS: The expression of the IL-10 polarization marker cluster of differentiation 163 (CD163) was increased in SpA compared with RA intimal lining layer, but no differences were found in other M1 and M2 markers between the diseases. Furthermore, no significant phenotypic differences in monocytes and in vitro polarized monocyte-derived macrophages were seen between SpA, RA, and healthy controls, indicating that the differential CD163 expression does not reflect a preferential M2 polarization in SpA. More detailed analysis of intimal lining layer macrophages revealed a strong co-expression of the IL-10 polarization markers CD163 and cluster of differentiation 32 (CD32) but not any of the other markers in both SpA and RA. In contrast, synovial sublining macrophages had a more heterogeneous phenotype, with a majority of cells co-expressing M1 and M2 markers. CONCLUSIONS: The intimal lining layer but not synovial sublining macrophages display an IL-10 polarized-like phenotype, with increased CD163 expression in SpA versus RA synovitis. These differences in the distribution of the polarized macrophage subset may contribute to the outcome of chronic synovitis.
21558621 CD20 antigen imaging with ¹²⁴I-rituximab PET/CT in patients with rheumatoid arthritis. 2011 INTRODUCTION: Visualization of the CD20-antigen expression could provide a tool to localize sites of inflammation and could be of additive value in the diagnosis, and subsequently, in the treatment follow-up of patients with rheumatoid arthritis. In this study, an anti-CD20 monoclonal antibody, rituximab (Mabthera®), was radiolabeled with ¹²⁴Iodine. We report the first results of I¹²⁴-rituximab PET/CT in patients with rheumatoid arthritis. METHODS: Eligible patients received 50 MBq ¹²⁴I-rituximab. Wholebody PET/CT imaging was performed at 10 min, 24 h, 48 h and 72-96 h post injection. Images were evaluated primarily on a visual basis and were correlated with disease activity as determined by physical examination and clinical measures. RESULTS: Joints with visually detectable targeting of ¹²⁴I-rituximab were observed in 4 out of 5 evaluable patients. Only the images at 24 h and later showed accumulation in joints, indicating that the visualized signal represented active targeting of rituximab to the CD20 antigen. Several images showed CD20 positive B-cell infiltration in joints which were clinically normal, while a few clinically diagnosed arthritis localizations were not visualized. This discrepancy suggests that infiltration of CD20 positive B-cells in synovium is a phenomenon that is at least partially independent of clinical inflammation. The level of uptake in joints was generally low, representing less than 0.5% of the injected dose. CONCLUSION: We have shown the feasibility of CD20 antigen imaging using ¹²⁴I-rituximab in patients with rheumatoid arthritis. Further research is needed to elucidate the clinical significance of demonstrated B-cell infiltration in rheumatic joints.
22810731 Taurine and inflammatory diseases. 2014 Jan Taurine (2-aminoethanesulfonic acid) is the most abundant free amino acid in humans and plays an important role in several essential biological processes such as bile acid conjugation, maintenance of calcium homeostasis, osmoregulation and membrane stabilization. Moreover, attenuation of apoptosis and its antioxidant activity seem to be crucial for the cytoprotective effects of taurine. Although these properties are not tissue specific, taurine reaches particularly high concentrations in tissues exposed to elevated levels of oxidants (e.g., inflammatory cells). It suggests that taurine may play an important role in inflammation associated with oxidative stress. Indeed, at the site of inflammation, taurine is known to react with and detoxify hypochlorous acid generated by the neutrophil myeloperoxidase (MPO)-halide system. This reaction results in the formation of less toxic taurine chloramine (TauCl). Both haloamines, TauCl and taurine bromamine (TauBr), the product of taurine reaction with hypobromous acid (HOBr), exert antimicrobial and anti-inflammatory properties. In contrast to a well-documented regulatory role of taurine and taurine haloamines (TauCl, TauBr) in acute inflammation, their role in the pathogenesis of inflammatory diseases is not clear. This review summarizes our current knowledge concerning the role of taurine, TauCl and TauBr in the pathogenesis of inflammatory diseases initiated or propagated by MPO-derived oxidants. The aim of this paper is to show links between inflammation, neutrophils, MPO, oxidative stress and taurine. We will discuss the possible contribution of taurine and taurine haloamines to the pathogenesis of inflammatory diseases, especially in the best studied example of rheumatoid arthritis.
22018186 Effects on joint destruction and remission, bone turnover and lack of influence on atherog 2011 Sep As early as in 1948 a woman with severe rheumatoid arthritis (RA) was successfully treated with glucocorticoids. However, not until recently has the role of GCs in the treatment of RA been clarified and supported by scientific evidence in a limited number of randomised studies. The present article reviews four reports from the BARFOT (Better Anti-Rheumatic FarmacOTherapy) low-dose prednisolone study based on 250 patients with early RA. These patients were randomised to have either DMARDs only or DMARDs plus prednisolone 7.5 mg daily for two years. It was shown that low-dose prednisolone in addition to a DMARD was superior to DMARDs alone in the ability to inhibit joint damage and induce clinical remission. A follow-up study demonstrated that remission after 2 years with low-dose prednisolone was associated with reduced joint destruction also after 4 years. Prednisolone had no or minor effects on bone density and the frequency of adverse effects was small. A third article measuring markers of bone synthesis and resorption demonstrated that the suppressive effect on bone synthesis exerted by prednisolone was counteracted by the ability of prednisolone to hamper the inflammatory mediated increase in bone resorption. In a fourth article assessing intima-media thickness and endothelial function, no influence of prednisolone 7.5 mg daily on atherosclerosis was observed. Altogether, these four studies provide evidence for recommending low-dose prednisolone treatment in combination with DMARDs for at least two years to patients with recent onset RA.
21550343 Progranulin: a promising therapeutic target for rheumatoid arthritis. 2011 Dec 1 Progranulin (PGRN) is an autocrine growth factor with multiple functions. This review provides updates about the interplays of PGRN with extracellular matrix proteins, proteolytic enzymes, inflammatory cytokines, and cell surface receptors in cartilage and arthritis, with a special focus on the interaction between PGRN and TNF receptors (TNFR) and its implications in inflammatory arthritis. The paper also highlights Atsttrin, an engineered protein composed of three PGRN fragments that prevents inflammation in several inflammatory arthritis models. Identification of PGRN as a ligand of TNFR and an antagonist of TNFα signaling, together with the discovery of Atsttrin, not only betters our understanding of the pathogenesis of arthritis, but also provides new therapeutic interventions for various TNFα-mediated pathologies and conditions, including rheumatoid arthritis.
20837497 Haematopoietic stem and progenitor cells in rheumatoid arthritis. 2011 Feb RA is the prototypic chronic inflammatory disease, characterized by progressive articular cartilage and bone destruction. The systemic nature of RA is evidenced by the increased risk of atherosclerosis and lymphoproliferative disorders. Components of both the innate and adaptive immune system are implicated in the pathophysiology of the articular and extra-articular manifestations of the disease. A fundamental process in the onset of RA is the breakdown in self-tolerance. Accelerated ageing of immune cells (immunosenescence) appears to be a major mechanism favouring the disruption of tolerance. Telomere erosion, a hallmark of immunosenescence, is present in lymphoid (naïve and memory T cells) and myeloid (granulocytes) cells in RA. The premature ageing process also involves the haematopoietic stem and progenitor cells (CD34(+) HSPC), thus extending the RA immunopathogenesis to include early events in the shaping of the immune system. This review summarizes current concepts of HSPC ageing and its impact on immune regeneration, highlighting the phenotypic and functional similarities between elderly and RA HSPC.
21804099 Developing tolerogenic dendritic cell therapy for rheumatoid arthritis: what can we learn 2011 Sep One of the therapeutic strategies under development for the treatment of rheumatoid arthritis is based on reinstating immune tolerance by vaccination with autologous dendritic cells with potent tolerogenic function. These tolerogenic dendritic cells (TolDC) can be generated ex vivo and have beneficial therapeutic effects in animal models of arthritis. Although experimental animal models have been instrumental in the development of this novel immunotherapeutic tool, several outstanding questions regarding the application of TolDC remain to be addressed. This paper reviews what has been learnt to date from studying the therapeutic potential of TolDC in animal models of arthritis and discusses issues relating to preventive versus curative effects of TolDC, the antigen specificity of TolDC therapy, the route, dose and frequency of TolDC administration and the safety of TolDC treatment. Lessons learnt from animal models will aid the design of clinical trials with TolDC.
20851020 Traditional cardiovascular risk factors in rheumatoid arthritis: a meta-analysis. 2011 Mar OBJECTIVE: Rheumatoid arthritis is associated with increased cardiovascular morbidity and mortality. We performed a systematic review of the literature and a meta-analysis to look for differences in the prevalence of traditional cardiovascular risk factor between RA patients and controls. METHODS: Medline database was searched to identify studies evaluating the prevalence of traditional cardiovascular risk factors in rheumatoid arthritis patients and controls. Studies were selected and reviewed by two investigators. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated and pooled using a random-effects model. Statistical heterogeneity was evaluated through the use of Chi2 and I2 statistics. RESULTS: Fifteen case-control studies with a total of 2956 patients and 3713 controls met the inclusion criteria. The prevalence of smoking was increased in RA patients in comparison with controls: OR (95%CI) 1.56 (1.35-1.80) (P < 0.00001). The prevalence of hypertension did not differ: OR (95% CI) 1.09 (0.91-1.31) (P = 0.35). The prevalence of diabetes mellitus was increased in RA: OR (95%CI) 1.74 (1.22-2.50) (P = 0.003). The prevalence of hypercholesterolemia did not differ: OR (95%CI) 0.84 (0.67-1.04) (P = 0.11). HDL cholesterol levels were lower in RA patients: weighted mean difference -17.72 mg/dl (-18.35 - -17.08) (P < 0.00001). Significant heterogeneity among studies was found for diabetes mellitus and HDL cholesterol levels. CONCLUSIONS: Some traditional cardiovascular risk factors, such as smoking, diabetes mellitus or lower HDL cholesterol levels, appear more prevalent in rheumatoid arthritis patients and could contribute to the increased cardiovascular morbidity and mortality observed in rheumatoid arthritis.
22337939 Sustained drug-free remission in rheumatoid arthritis after DAS-driven or non-DAS-driven t 2012 Jun OBJECTIVES: To compare the prevalence of and predictors for sustained drug-free remission in two cohorts of patients with recent-onset RA treated with DAS-driven therapy or non-DAS-driven therapy. METHODS: Sustained drug-free remission was assessed after 5 years of follow-up in 508 patients treated with DAS-driven therapy (DAS ≤ 2.4) in a randomized treatment cohort, and in 424 patients who received non-DAS-driven therapy in a prospective inception cohort. The design of the DAS-driven cohort required systematic joint assessments with DAS-driven restart of therapy. Predictors for remission were identified by univariable and multivariable logistic regression in each cohort separately and in a combined multivariate logistic regression analysis corrected for propensity scores, including a sensitivity analysis on patients receiving initial monotherapy. RESULTS: Patients in the DAS-driven cohort had more active disease at baseline, but the prevalence of sustained drug-free remission was similar after DAS-driven (9.8%) and non-DAS-driven therapy (10.6%). Among patients with ACPA, drug-free remission was more frequently achieved after DAS-driven than after non-DAS-driven therapy (5.4 vs. 2.1%, OR = 2.68, 95% CI 0.97, 7.43). Absence of ACPA and short symptom duration were independent predictors for sustained drug-free remission in both cohorts. Initial treatment choice and inclusion period were not predictive. The sensitivity analysis yielded comparable results. CONCLUSION: Retrospectively comparing a DAS-driven to a non-DAS-driven therapy cohort, the occurrence and predictors of sustained drug-free remission were similar. The DAS-driven cohort had a more unfavourable prognosis. DAS-driven therapy may improve the chance of sustained drug-free remission in ACPA-positive patients with recent-onset RA.
21053358 Nonmelanoma skin cancer in inflammatory bowel disease: a review. 2011 Jun At least 1 million new cases of nonmelanoma skin cancer (NMSC) are diagnosed in the United States each year and the incidence is increasing. A higher incidence of NMSC in organ transplant recipients on immunosuppression has been documented for some time, and recent studies indicate that patients with inflammatory bowel disease (IBD), particularly those treated with immunosuppressive medications, might also be at higher risk for this condition. In this review we summarize recent data evaluating the associations between immunomodulators, antitumor necrosis factor-α biologic agents and NMSC in patients with IBD and other autoimmune conditions such as rheumatoid arthritis. We also offer recommendations for prevention of NMSC in these populations.
23219770 Tight control applied to the biological therapy of rheumatoid arthritis. 2013 Jun In the last decade, treatment strategies for rheumatoid arthritis (RA) have included the early use of disease-modifying anti-rheumatic drugs, since prompt suppression of disease activity is associated with a reduction in radiological damage. This strategy has now been incorporated into the broader concept of "tight control", defined as a treatment strategy tailored to each patient with RA, which aims to achieve a predefined level of low disease activity or remission within a certain period of time. To pursue this goal, tight control should include careful and continuous monitoring of disease activity, and early therapeutic adjustments or switches should be considered as necessary. It is noteworthy that the key role of tight control of RA has been stressed by the recent EULAR Guidelines. This review discusses the most recent evidence concerning the role of a tight control strategy in the treatment of RA, and on how this strategy should be pursued.
23052485 The effect of intra-articular injection of different concentrations of ozone on the level 2013 May The objectives of this study were to observe the therapeutic effect of ozone (O3) of different concentrations on rat with rheumatoid arthritis (RA), and to investigate the role of O3 in regulating the level of TNF-α (tumor necrosis factor), TNF-R1 (tumor necrosis factor receptor 1), and TNF-R2. Forty-eight Wistar rats were randomly divided into eight groups. There are five O3 groups which were marked by 10, 20, 30, 40, and 50 μg/mL, respectively, control group, oxygen group, and RA model group. RA was induced in all rats by hypodermic injection of collagen II and complete Freund's adjuvant except that in the control group. At 21 days after modeling, the rats in oxygen group were given an injection of oxygen in the knee joint weekly for 3 weeks, and the rats in O3 groups were injected the concentration of O3 as they marked weekly for 3 weeks. The thickness of hind paw, as well as the serum and synovial levels of TNF-α, TNF-R1, and TNF-R2 was observed. At the end of treatments, the thickness of the hind paws in O3-40 group is much less compared to RA group (P < 0.01). The serum levels of TNF-α, TNF-R1, and TNF-R2 showed no significant difference among all the groups (P > 0.05). However, the synovial levels of TNF-α and TNF-R2 in O3-40 and O3-50 groups are lower than those in RA group (P < 0.01). The synovial level of TNF-R1 in O3-40 group is higher than that in RA group (P < 0.05). In conclusion, intra-articular injection of O3 at 40 μg/mL can effectively suppress the joint swelling caused by RA. This mechanism is probably mediated by down-regulating synovial TNF-α and TNF-R2 and up-regulating TNF-R1 in the joint.
21743088 Longitudinal levels of apolipoproteins and antibodies against phosphorylcholine are indepe 2011 Oct OBJECTIVE: RA is associated with premature atherosclerosis. Here, we determined the associations of apolipoproteins and immunoglobulin M (IgM) antibodies against phosphorylcholine (anti-PC) with carotid artery atherosclerosis in a prospective cohort of patients with early RA. METHODS: In all 114 patients, age 50.6 (11.2) years, 68.4% women, with recent RA (<12 months after symptoms onset) were included and assessed at 0, 3, 12, 24 and 60 months after RA diagnosis. At the same time points, apolipoproteins were determined by immunoturbidimetry, and IgM anti-PC by ELISA. Carotid intima-media thickness (cIMT) (common carotid) and occurrence of plaques (common, internal and external carotids) were the principal study outcomes, which were examined with high-resolution B-mode ultrasonography after 5 years of RA disease. Mixed linear modelling and generalized estimating equations (GEEs) were used for longitudinal statistical analyses. RESULTS: Multivariate regression analyses showed that age, male gender, smoking (ever) and history of cardiovascular disease (CVD), hypertension or diabetes mellitus, but no other baseline variables, had independent associations with cIMT (P < 0.05). Plaque detection was positively associated with age and smoking (ever). After adjustment, a longitudinal approach demonstrated an independent negative prediction of cIMT by apoA1 (P = 0.047), but a positive by apoB/apoA1 ratio (P = 0.030). Higher levels of pro-atherogenic apolipoproteins over time, apoB and apoB/apoA1 ratio, and low anti-PC tertile were independently associated with enhanced detection of bilateral carotid plaque (P = 0.002, 0.026 and 0.000, respectively). Both baseline and longitudinal levels of inflammatory/disease-related factors failed to show significant associations with the study outcomes. CONCLUSION: Apolipoproteins and anti-PC may have independent roles in subclinical atherosclerosis in patients with RA.
23094684 Rheumatoid neutrophilic dermatosis with tense blister formation: a case report and review 2014 Feb We report a 78-year-old woman with rheumatoid neutrophilic dermatosis (RND) presenting with tense blisters; an extremely rare manifestation of this condition. Systemic corticosteroid was of limited efficacy, while dapsone was effective. A literature review of four similar cases showed that tense blisters in this type of RND tended to appear on the lower extremities of aged, female rheumatoid arthritis patients. Of note, half of the cases were resistant to corticosteroids, as anti-neutrophil agents are reported to be effective. Accordingly, it is important to recognise this unusual manifestation for the timely initiation of appropriate therapy.
23023360 Female with rash, acute kidney failure and rheumatoid arthritis. 2012 Jul This case describes a 42-year-old female with longstanding history of rheumatoid arthritis (RA) and Felty syndrome (FS). She presented with acute renal kidney failure, skin rash and hemoptysis. A clinical suspicion of small vessel vasculitis (SVV) was thought, serology was also positive for various markers of SVV. However, these serology markers could be false-positive in a patient of rheumatoid arthritis. A renal biopsy was performed that led to the final diagnosis of cryoglobulinemic vasculitis. Patient was managed according to the standard guidelines for therapy (plasmafiltration and immunosuppression). It is challenging to manage a patient of RA, in the presence of Felty syndrome-related granulocytopenia and thrombocytopenia. Patient initially showed signs of improvement, but finally succumbed to complications of therapy. The case provides insight into the diagnosis and management of such cases.
22942402 A randomized controlled trial of a cognitive behavioural patient education intervention vs 2013 Jan OBJECTIVES: Cardiovascular disease (CVD) is responsible for 50% of the excess mortality for patients with RA. This study aimed to evaluate a novel 8-week cognitive behavioural patient education intervention designed to effect behavioural change with regard to modifiable CVD risk factors in people with RA. METHODS: This was a non-blinded randomized controlled trial with a delayed intervention arm. Participants were randomly assigned to receive the cognitive behavioural education intervention or a control information leaflet at a ratio of 1:1. The primary outcome measure was patient's knowledge of CVD in RA; secondary measures were psychological measures relating to effecting behaviour change, actual behaviour changes and clinical risk factors. Data were collected at baseline, 2 and 6 months. RESULTS: A total of 110 participants consented (52 in the intervention group and 58 in the control group) to participate in the study. At 6 months, those in the intervention group had significantly higher knowledge scores (P < 0.001); improved behavioural intentions to increase exercise (P < 0.001), eat a low-fat diet (P = 0.01) and lose weight (P = 0.06); and lower mean diastolic blood pressure by 3.7 mmHg, whereas the control group's mean diastolic blood pressure increased by 0.8 mmHg. There was no difference between the groups on actual behaviours. CONCLUSIONS: Patient education has a significant role to play in CVD risk factor modification for patients with RA, and the detailed development of this programme probably contributed to its successful results. It is disappointing that behaviours, as we measured them, did not change. The challenge, as always, is how to translate behavioural intentions into action. Larger studies, powered specifically to look at behavioural changes, are required. Trial registration. National Institute for Health Research, UKCRN 4566.
21091389 Lumbar radiculopathy caused by foraminal stenosis in rheumatoid arthritis. 2011 May STUDY DESIGN: Case-series study. OBJECTIVE: To describe the clinical presentation, characteristic findings of imaging studies, and treatment of lumbar radiculopathy caused by foraminal stenosis in rheumatoid arthritis. BACKGROUND. Lumbar lesions in rheumatoid arthritis are relatively rare, with a limited number of systemic reports. METHODS: Six patients with lumbar radiculopathy caused by foraminal stenosis in rheumatoid arthritis were treated. The patients were all women with a mean age of 69 years and mean rheumatoid arthritis duration of 15 years. The medical records and imaging studies of all patients were reviewed. RESULTS: The affected nerve roots were L4 in four patients and L3 in two patients. Foraminal stenosis was not demonstrated in magnetic resonance images in four of the six patients. Selective radiculography with nerve root block reproduced pain, manifested blocking effect, and demonstrated compression of the nerve root by the superior articular process of the lower vertebra in all patients. Conservative treatment was performed on one patient, and surgery was conducted for the rest of the five patients; radiculopathy was improved in all patients. CONCLUSIONS: Lumbar foraminal stenosis is a characteristic pathology of rheumatoid arthritis, and should be kept in mind in the diagnosis of lumbar radiculopathy. Selective radiculography is useful in the diagnosis of affected nerve roots.
22584083 Elevated levels of fibrinogen-derived endogenous citrullinated peptides in synovial fluid 2012 May 14 INTRODUCTION: Rheumatoid arthritis (RA) is an autoimmune disease characterized by inflammation of the joints and the presence of autoantibodies directed against proteins containing the non-standard arginine-derived amino acid citrulline. The protein fibrinogen, which has an essential role in blood clotting, is one of the most prominent citrullinated autoantigens in RA, particularly because it can be found in the inflamed tissue of affected joints. Here, we set out to analyze the presence of citrullinated endogenous peptides in the synovial fluid of RA and arthritic control patients. METHODS: Endogenous peptides were isolated from the synovial fluid of RA patients and controls by filtration and solid phase extraction. The peptides were identified and quantified using high-resolution liquid chromatography-mass spectrometry. RESULTS: Our data reveal that the synovial fluid of RA patients contains soluble endogenous peptides, derived from fibrinogen, containing significant amounts of citrulline residues and, in some cases, also phosphorylated serine. Several citrullinated peptides are found to be more abundantly present in the synovial fluid of RA patients compared to patients suffering from other inflammatory diseases affecting the joints. CONCLUSIONS: The increased presence of citrullinated peptides in RA patients points toward a possible specific role of these peptides in the immune response at the basis of the recognition of citrullinated peptides and proteins by RA patient autoantibodies.
21658310 Complement system and rheumatoid arthritis: relationships with autoantibodies, serological 2011 Apr Autoantibodies (rheumatoid factor, RF; anti-citrullinated-protein antibodies, ACPA) and complement system are involved in rheumatoid arthritis (RA). ACPA and anti-TNF agents are capable of in vitro modulating complement activity. We investigated the relationships between complement, autoantibodies, and anti-TNF treatment in vivo. One-hundred fourteen RA patients (89F/25M), diagnosed according to 1987 ACR criteria, and 30 healthy controls were enrolled. Serological analysis included ESR, CRP, complement C3, C4 and CH50, RF and ACPA (ELISA, cut-off>20 U/ml). Split-products (SP) of C3 and B were studied by immunoelectrophoresis/counterimmunoelectrophoresis. Seventy-six patients started anti-TNF treatment and were studied at baseline and after 22 weeks. Disease activity was measured with DAS28 and response to therapy with EULAR criteria. At baseline, RA patients showed significantly higher levels of C3 and C4 than controls (C3 127.9±26.5 vs 110±25 mg/dl, P=0.0012; C4 29.7±10.2 vs 22.7±8.3mg/dl, P=0.0003). No differences in C3, C4 and CH50 levels were observed between ACPA+ (n=76) and ACPA- (n=38) patients. After 22 weeks of anti-TNF, C3, C4 and RF were significantly reduced (P<0.003, <0.005 and <0.04, respectively) and RF changes showed negative correlation with CH50. SP of C3 and B were observed neither at baseline nor after 22 weeks. DAS28 significantly improved after 22 weeks. Patients showing higher baseline C3 or lower reduction of C3 levels after 22 weeks had a worse EULAR outcome (X2=22.793, P<0.001). RF levels seem to correlate with complement CH50. The presence of high levels of C3 in RA patients may reflect a pro-inflammatory status and represent a negative prognostic factor for anti-TNF therapy.