975 resultados para Rheumatoid Factor


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Autoantibodies in early rheumatoid arthritis (RA) have important diagnostic value. The association between the presence of autoantibodies against cyclic citrullinated peptide and the response to treatment is controversial. To prospectively evaluate a cohort of patients with early rheumatoid arthritis (< 12 months of symptoms) in order to determine the association between serological markers (rheumatoid factor (RF), anti-citrullinated protein antibodies) such as anti-cyclic citrullinated peptide antibodies (anti-CCP) and citrullinated anti-vimentin (anti-Sa) with the occurrence of clinical remission, forty patients diagnosed with early RA at the time of diagnosis were evaluated and followed for 3 years, in use of standardized therapeutic treatment. Demographic and clinical data were recorded, disease activity score 28 (DAS 28), as well as serology tests (ELISA) for RF (IgM, IgG, and IgA), anti-CCP (CCP2, CCP3, and CCP3.1) and anti-Sa in the initial evaluation and at 3, 6, 12, 18, 24, and 36 months of follow-up. The outcome evaluated was the percentage of patients with clinical remission, which was defined by DAS 28 lower than 2.6. Comparisons were made through the Student t test, mixed-effects regression analysis, and analysis of variance (significance level of 5%). The mean age was 45 years, and a female predominance was observed (90%). At the time of diagnosis, RF was observed in 50% of cases (RF IgA-42%, RF IgG-30%, and RF IgM-50%), anti-CCP in 50% (no difference between CCP2, CCP3, and CCP3.1) and anti-Sa in 10%. After 3 years, no change in the RF prevalence and anti-CCP was observed, but the anti-Sa increased to 17.5% (P = 0.001). The percentage of patients in remission, low, moderate, and intense disease activity, according to the DAS 28, was of 0, 0, 7.5, and 92.5% (initial evaluation) and 22.5, 7.5, 32.5, and 37.5% (after 3 years). There were no associations of the presence of autoantibodies in baseline evaluation and in serial analysis with the percentage of clinical remission during follow-up of 3 years The presence of autoantibodies in early RA has no predictive value for clinical remission in early RA.

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Rheumatoid inflammation is characterised by the production of rheumatoid factor antibodies directed against denatured IgG. Oxygen free radicals have the potential to denature all manner of proteins and can be generated by activated phagocytic cells in the inflamed joint. By modifying routine ELISA and nephelometric procedures for measuring rheumatoid factor, (i.e. substituting free radical altered IgG for rabbit and heat aggregated IgG as antigens) we have observed that oxygen radicals, generated by (1) UV light and (2) PMA-activated neutrophils, give rise to monomeric and polymeric forms of IgG which have increased reactivity towards IgM and IgA polyclonal rheumatoid factor antibodies. We conclude that free radical alteration of IgG may be a stimulus to the formation of immune complexes with rheumatoid factor antibody, thereby promoting and amplifying tissue damage during rheumatoid inflammation.

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Immunoglobulin G from rheumatoid patients is denatured around the hinge region. This has been proposed as an explanation for the presence of circulating autoantibodies to IgG in these patients. It has previously been suggested that oxygen radicals (OR) derived from activated polymorphs may play a role in denaturation in vivo. Using sera from rheumatoid patients and age-matched controls in a modified ELISA technique, we have investigated the potential for polyclonal rheumatoid factors (RF) to bind to OR denatured IgG. Three model systems were used to generate OR in vitro: (a) purified PMN s activated by the cell surface stimulant PMA, (b) radiolysis of IgG in solution to generate specifically the superoxide radical and, in a separate system, the hydroxyl radical, (OH.), (c) purified myeloperoxide in the presence of H2O2 and halide ions. Results: 1. The binding of both IgA and IgM RF s to PMN denatured IgG increased dose dependently for seropositive sera only. 2. The OH. radical but not the superoxide radical significantly increased the binding of IgA and M RF, again only for seropositive sera. 3. The myeloperoxidase enzyme system did not increase RF binding. 4. IgG incubated with elastase was not found to be a better antigen than native IgG. These results indicate that IgG is denatured by OR released from activated PMN, thereby producing an antigen for polyclonal RF s.

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Introduction: The receptor for advanced glycation end products (RAGE) is a member of the immunoglobulin superfamily of cell surface receptor molecules. High concentrations of three of its putative proinflammatory ligands, S100A8/A9 complex (calprotectin), S100A8, and S100A12, are found in rheumatoid arthritis (RA) serum and synovial fluid. In contrast, soluble RAGE (sRAGE) may prevent proinflammatory effects by acting as a decoy. This study evaluated the serum levels of S100A9, S100A8, S100A12 and sRAGE in RA patients, to determine their relationship to inflammation and joint and vascular damage. Methods: Serum sRAGE, S100A9, S100A8 and S100A12 levels from 138 patients with established RA and 44 healthy controls were measured by ELISA and compared by unpaired t test. In RA patients, associations with disease activity and severity variables were analyzed by simple and multiple linear regressions. Results: Serum S100A9, S100A8 and S100A12 levels were correlated in RA patients. S100A9 levels were associated with body mass index (BMI), and with serum levels of S100A8 and S100A12. S100A8 levels were associated with serum levels of S100A9, presence of anti-citrullinated peptide antibodies (ACPA), and rheumatoid factor (RF). S100A12 levels were associated with presence of ACPA, history of diabetes, and serum S100A9 levels. sRAGE levels were negatively associated with serum levels of C-reactive protein (CRP) and high-density lipoprotein (HDL), history of vasculitis, and the presence of the RAGE 82Ser polymorphism. Conclusions: sRAGE and S100 proteins were associated not just with RA inflammation and autoantibody production, but also with classical vascular risk factors for end-organ damage. Consistent with its role as a RAGE decoy molecule, sRAGE had the opposite effects to S100 proteins in that S100 proteins were associated with autoantibodies and vascular risk, whereas sRAGE was associated with protection against joint and vascular damage. These data suggest that RAGE activity influences co-development of joint and vascular disease in rheumatoid arthritis patients.

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Objectives. To confirm the association of a functional single-nucleotide polymorphism (SNP), C1858T (rs2476601), in the PTPN22 gene of British Caucasian rheumatoid arthritis (RA) patients and to evaluate its influence on the RA phenotype. Methods. A total of 686 RA patients and 566 healthy volunteers, all of British Caucasian origin, were genotyped for C1858T polymorphism by PCR-restriction fragment length polymorphism assay. Data were analysed using SPSS software and the χ 2 test as applicable. Results. The PTPN22 1858T risk allele was more prevalent in the RA patients (13.9%) compared with the healthy controls (10.3%) (P = 0.008, odds ratio 1.4, 95% confidence interval 1.09-1.79). The association of the T allele was restricted to those with rheumatoid factor (RF)-positive disease (n = 524, 76.4%) (P = 0.004, odds ratio 1.5, 95% confidence interval 1.1-1.9). We found no association between PTPN22 and the presence of the HLA-DRB1 shared epitope or clinical characteristics. Conclusions. We confirmed the previously reported association of PTPN22 with RF-positive RA, which was independent from the HLA-DRB1 genotype.

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The joint fluids of 37 patients with rheumatoid arthritis, eight patients with traumatic injuries to their joints, two patients with Reiter's syndrome and three patients with psoriatic arthritis were tested for the presence of B cell colony stimulating activity (B cell CSA). B cell CSA was found in all of the joint fluids from the patients with rheumatoid arthritis but in none of the joint fluids from patients with traumatic injuries to their joints or in the joint fluids from the patients with Reiter's syndrome. A trace of B cell CSA was found in the joint fluid of one of the three patients with psoriatic arthritis. There was a positive correlation (r = 0.796) between the amount of rheumatoid factor present in the joint fluids and the titre of B cell CSA. This correlation was highly significant (P less than 0.001). The B cell CSA was localized to component(s) with molecular weight ranges 115-129 kD and 64-72 kD and an isoelectric point of 6.8. Its activity was sensitive to reduction with 2-mercaptoethanol and to the oxidising action of potassium periodate.

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To investigate pregnancy related changes of rheumatoid factor (RF) isotypes and anti-citrullinated protein antibodies (ACPA) and their association with disease activity and therapy in patients with rheumatoid arthritis.

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Aseptic pachymeningitis is a rare and serious complication of rheumatoid arthritis (RA). Herein, we describe a patient with rheumatoid factor-positive and anti-cyclic citrullinated peptide-positive RA who experienced a focal seizure, with aphasia and convulsions of the right side of the body. The findings of magnetic resonance imaging and histologic analysis led to a diagnosis of rheumatoid pachymeningitis. Because the patient had a large number of CD20-expressing B lymphocytes, therapy with rituximab was started and has resulted in complete and sustained remission of both the pachymeningitis and the RA for >2 years. Despite a decrease in immunoglobulins, the patient has remained free of infections, which illustrates the favorable outcome that can result from therapeutic B cell depletion in this potentially lethal manifestation of RA.

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Introduction Reconstitution of peripheral blood (PB) B cells after therapeutic depletion with the chimeric anti-CD20 antibody rituximab (RTX) mimics lymphatic ontogeny. In this situation, the repletion kinetics and migratory properties of distinct developmental B-cell stages and their correlation to disease activity might facilitate our understanding of innate and adaptive B-cell functions in rheumatoid arthritis (RA). Methods Thirty-five 'RTX-naïve' RA patients with active arthritis were treated after failure of tumour necrosis factor blockade in an open-label study with two infusions of 1,000 mg RTX. Prednisone dose was tapered according to clinical improvement from a median of 10 mg at baseline to 5 mg at 9 and 12 months. Conventional disease-modifying antirheumatic drugs were kept stable. Subsets of CD19+ B cells were assessed by flow cytometry according to their IgD and CD27 surface expression. Their absolute number and relative frequency in PB were followed every 3 months and were determined in parallel in synovial tissue (n = 3) or synovial fluid (n = 3) in the case of florid arthritis. Results Six of 35 patients fulfilled the European League Against Rheumatism criteria for moderate clinical response, and 19 others for good clinical response. All PB B-cell fractions decreased significantly in number (P < 0.001) after the first infusion. Disease activity developed independently of the total B-cell number. B-cell repopulation was dominated in quantity by CD27-IgD+ 'naïve' B cells. The low number of CD27+IgD- class-switched memory B cells (MemB) in the blood, together with sustained reduction of rheumatoid factor serum concentrations, correlated with good clinical response. Class-switched MemB were found accumulated in flaring joints. Conclusions The present data support the hypothesis that control of adaptive immune processes involving germinal centre-derived, antigen, and T-cell-dependently matured B cells is essential for successful RTX treatment.

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There is growing support for the theory that an interaction between the immune and reproductive/endocrine systems underlies the pathogenesis of autoimmune rheumatic diseases. Most of the recent evidence derives from studies of sex hormones and pregnancy in women with systemic lupus. Other than an ameliorative effect of pregnancy, little is known about reproductive factors in relation to rheumatoid arthritis. To elucidate the relationship, a population-based retrospective study was undertaken. Included were 378 female residents of Olmsted County, Minnesota diagnosed with rheumatoid arthritis between 1950 and 1982 (cases) and 325 arthritis-free, married female controls matched to the 324 married cases on birth-year, age at first marriage, and duration of Olmsted County residency. Information of reproductive factors was extracted from the medical records system maintained by the Mayo Clinic.^ Cases had lower fertility rates compared with the female population of Minnesota (rate ratio = 0.86, 95% confidence interval (CI)= 0.80-0.92). Fertility was significantly reduced even prior to the onset of rheumatoid factor positive arthritis. Restricting the comparison to married Olmsted County residents did not alter the results. Further adjustments for time not at risk of conception using survival analysis and proportional hazards modeling only intensified the fertility reduction in the married cases compared with controls. Nulligravidity was more common among cases than controls (odds ratio = 3.16, CI = 1.61-6.20). Independent of fertility, pregnancy had a protective effect against rheumatoid arthritis (odds ratio = 0.31, CI = 0.11-0.89), which was dramatically reversed in the 12 months postpartum (odds ratio = 4.67, CI = 1.50-14.47). Cases were younger at menopause than controls (p $<$ 0.01).^ Small but statistically insignificant associations were observed between rheumatoid arthritis and the following factors: increased frequency of complaints to a physician of infertility; increased frequency of spontaneous abortion, premature birth, and congenital malformations following arthritis onset; and increased prevalence of menopause at arthritis onset. Cases did not differ from controls on age at menarche, duration of pregnancy, or birth weight.^ The findings provide further support for the involvement of the reproductive/endocrine systems in the pathogenesis of autoimmune rheumatic disease. The search for biological mechanisms should be intensified. ^

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Objective. Since 1996, autologous hemopoietic stem cell transplantation (HSCT) has been used to treat severe rheumatoid arthritis (RA). To date, published reports have been individual cases or series containing small numbers. This study combined the worldwide experience in a single analysis. Methods. The Autoimmune Disease Databases of the European Group for Blood and Marrow Transplantation (EBMT) and the Autologous Blood and Marrow Transplant Registry (ABMTR) were used to identify patients with RA treated with autologous HSCT. Further information relating to patient and treatment-specific variables was obtained by questionnaire. Results. Seventy-six patients were registered from 15 centers. Seventy-three patients had received autologous HSCT, and in 3 patients hematopoietic stem cells (HSC) were mobilized but not transplanted. Transplanted patients (median age 42 yrs, 74% female, 86% rheumatoid factor positive) had been previously treated with a mean of 5 (range 2-9) disease modifying antirheumatic drugs (DMARD). Significant functional impairment was present, with a median Health Assessment Questionnaire (HAQ) score of 1.4 (range 1.1-2.0) and Steinbrocker score mean 2.39 (SD 0.58). The high dose treatment regimen was cyclophosphamide (CYC) alone in the majority of patients, mostly 200 mg/kg (n = 62). Seven patients received anti-thymocyte globulin (ATG) in addition to CYC, 2 patients busulfan and CYC (BuCYC), and one patient CYC with total body irradiation and ATG. One patient received fludarabine with ATG. Following treatment, one patient received bone marrow but the rest received chemotherapy and/or granulocyte colony-stimulating factor mobilized peripheral blood stem cells. The harvest was unmanipulated in 28 patients, the rest receiving some form of lymphocyte depletion, mostly through CD34+ selection. Median followup was 16 months (range 3-55). Responses were measured using the American College of Rheumatology (ACR) criteria. Forty-nine patients (67%) achieved at least ACR 50% response at some point following transplant. There was a significant reduction in the level of disability measured by the HAQ (p < 0.005). Most patients restarted DMARD within 6 months for persistent or recurrent disease activity, which provided disease control in about half the cases. Response was significantly related to seronegative RA (p = 0.02) but not to duration of disease, number of previous DMARD, presence of HLA-DR4, or removal of lymphocytes from the graft. There was no direct transplant related mortality, although one patient, treated with the BuCYC regimen, died 5 months post-transplant from infection and incidental non-small cell lung cancer. Conclusion. Autologous HSCT is a relatively safe form of salvage treatment in severe, resistant RA. In these open label studies significant responses were achieved in most patients, with over 50% achieving an ACR 50 or more response at 12 months. Although the procedure is not curative, recurrent or persistent disease activity may be subsequently controlled in some patients with DMARD. Clinical trials are necessary to develop this approach inpatients with aggressive disease who have failed conventional treatment including anti-tumor necrosis factor agents.

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Transfusion of blood components has been associated with poor patient outcomes and, an overall increase in morbidity and mortality. Differences in the blood components arising from donor health, age and immune status may impact on outcomes of transfusion and transfusion-related immune modulation in recipients. The aim of this study was to investigate differences in inflammatory profile in donors and association with parameters including age, gender and deficiency status of pattern recognition molecule mannose-binding lectin (MBL). MBL level was determined by ELISA. Serum levels of interleukin (IL)-1α, IL-1β, IL-6, IL-8, IL-10, IL-12, tumour necrosis factor (TNF)-α, macrophage inflammatory protein (MIP)-1α, monocyte chemoattractant protein (MCP)-1, interferon (IFN)-α, and IFN-γ were examined by cytometric bead array (CBA). C-reactive protein (CRP) and rheumatoid factor (RF) were examined by immunoturbidimetry. This study demonstrated age was a parameter associated with the immune profile of blood donors, with significant increases in MCP-1 (p < 0.05) and RF (p < 0.05) and decreases in IL-1α evident in the older donors (61–76 years). Significant gender-associated differences in MCP-1, IL-12 and CRP plasma levels in the blood donor cohort were also reported. There was no significant difference in the level of any inflammatory markers studied according to MBL status. This study demonstrated that age and gender are associated with inflammatory profile in donors. These differences may be a factor impacting on outcomes of transfusion.

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Genetic susceptibility to juvenile idiopathic arthritis (JIA) was studied in the genetically homogeneous Finnish population by collecting families with two or three patients affected by this disease from cases seen in the Rheumatism Foundation Hospital. The number of families ranged in different studies from 37 to 45 and the total number of patients with JIA, from among whom these cases were derived, was 2 000 to 2 300. Characteristics of the disease in affected siblings in Finland were compared with a population-based series and with a sibling series from the United States. A thorough clinical and ophthalmological examination was made of all affected patients belonging to sibpair series. Information on the occurrence of chronic rheumatic diseases in parents was collected by questionnaire and diagnoses were confirmed from hospital records. All patients, their parents and most of the healthy sibs were typed for human leukocyte antigen (HLA) alleles in loci A, C, B, DR and DQ. The HLA allele distribution of the cases was compared with corresponding data from Finnish bone marrow donors. The genetic component in JIA was found to be more significant than previously believed. A concordance rate of 25% for a disease with a population prevalence of 1 per 1000 implied a relative risk of 250 for a monozygotic (MZ) twin. An estimate for the sibling risk of an affected individual was about 15- to 20-fold. The disease was basically similar in familial and sporadic cases; the mean age at disease onset was however lower in familial cases, (4.8 years vs 7.4 years). Three sibpairs (3.4 expected) were concordant for the presence of asymptomatic uveitis. Uveitis would thus not appear to have any genetic component of its own, separate from the genetic basis of JIA. Four of the parents had JIA (0.2 cases expected), four had a type of rheumatoid factor-negative arthritis similar to that seen in juvenile patients but commencing in adulthood, and one had spondyloarthropathy (SPA). These findings provide additional support for the conception of a genetic predisposition to JIA and suggest the existence of a new disease entity, JIA of adult onset. Both the linkage analysis of the affected sibpairs and the association analysis of nuclear families provided overwhelming evidence of a major contribution of HLA to the genetic susceptibility to JIA. The association analysis in the Finnish population confirmed that the most significant associations prevailed for DRB1*0801, DQB1*0402, as expected from previous observations, and indicated the independent role of Cw*0401.

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Os alelos HLA-DRB1, que codificam uma sequência de aminoácidos (QKRAA/QRRAA/RRRAA) nas posições 70 a 74 da terceira região hipervariável da cadeia 1 do gene DRB1, denominada epítopo compartilhado (EC), estão associados com maior susceptibilidade e gravidade para artrite reumatóide (AR) em diversas populações. Uma nova classificação proposta por Du Montcel et al tem sido desenvolvida para apurar a associação entre HLA-DRB1 e AR. Este estudo foi desenhado com o objetivo de determinar a frequência dos alelos HLA-DRB1 em pacientes brasileiros com AR, e sua associação com o fator reumatoide (FR), anticorpos antipeptídeos citrulinados (ACPA) e lesão radiográfica articular e óssea. Quatrocentos e doze pacientes com AR e 215 controles foram incluídos. A tipificação HLA-DRB1 foi realizada pela reação em cadeia de polimerase (PCR) usando primers específicos e hibridação com oligonucleotídeos de sequência específica (SSOP). A pesquisa de ACPA foi determinada pela técnica de ELISA e a do FR por nefelometria, a avaliação radiográfica realizada pelo método do índice de Sharp modificado de Van Der Heijde. Para análises estatísticas foram utilizados os testes do qui-quadrado, t de Student e a regressão logística. Nos pacientes com AR alelos HLA-DRB1*04:01, *04:04, *04:05 se associaram com AR (p<0,05), embora o amplo intervalo de confiança, vale a pena ressaltar a associação observada com o alelo DRB1*09:01 e a doença (p<0,05). Alelos HLA-DRB1 EC+ foram observados em 62,8% dos pacientes e em 31,1% do grupo controle (OR 3,62; p <0,001) e estiveram associados com ACPA (OR 2,03; p<0,001). Alelos DRB1 DERAA mostraram efeito protetor para a AR (OR 0,42; p<0,001). A análise da nova classificação de HLA-DRB1 mostra que S2 e S3P se associaram a AR (p<0,05). Alelos S2 e/ou S3P esteve presente em 65% dos pacientes e 32% do grupo controle (OR 3,86; p<0,001) e estiveram associados a ACPA (OR.2,11; p=0,001). Alelos S3D, S1, X mostraram efeito protetor para a AR. Os resultados obtidos neste estudo demonstram que pacientes brasileiros com AR de etnia majoritariamente mestiça, alelos HLA-DRB1 avaliados segundo a hipótese do EC e a classificação proposta por Du Montcel estiveram associados à suscetibilidade à doença e à presença de ACPA.