anti-CCP Negative Rheumatoid Arthritis Research Articles

Interleukin-20 is triggered by TLR ligands and associates with disease activity in patients with rheumatoid arthritis

BackgroundInterleukin (IL)-20 is a pro-inflammatory cytokine that may be implicated in the pathogenesis of rheumatoid arthritis (RA). This study aimed to determine the association between IL-20 and disease activity in patients with RA. MethodsThe levels of serum and synovial fluid IL-20 were measured in patients with RA and OA. The disease activity was assessed based on the Disease Activity Score of 28 joints (DAS28). The expression of IL-20 in synovial tissue samples from patients with RA and OA were determined by immunohistochemistry. Immunofluorescence staining was used to co-localize IL-20 with selected cells. The secretion of IL-20 was analysed in human peripheral blood mononuclear cells (PBMCs) of patients with RA. ResultsSynovial fluid and synovial tissue IL-20 were significantly increased in patients with RA compared with patients with OA. The expression of IL-20 in RA synovial tissue was particularly associated with macrophages and neutrophil granulocytes, but also with synovial fibroblasts and lymphocytes. The IL-20 levels in synovial fluid correlated with DAS28 (r=0.434; p=0.015) and were significantly elevated in anti-CCP positive RA compared with anti-CCP negative RA (122.3±104.1pg/ml and 45.9±35.8pg/ml; p=0.008). IL-20 production from PBMCs was induced by Poly I:C and LPS but not with pro-inflammatory cytokines, such as TNF-α or IL-1. ConclusionOur data showed that IL-20 is independently associated with RA disease activity and may be triggered by TLR ligands at local sites of inflammation.

VAV1 regulates experimental autoimmune arthritis and is associated with anti-CCP negative rheumatoid arthritis.

Rheumatoid arthritis (RA) patients can be stratified into two subgroups defined by the presence or absence of antibodies against citrullinated circular peptides (anti-CCP) with most of the genetic association found in anti-CCP positive RA. Here we addressed the role of VAV1, previously associated to multiple sclerosis (MS), in the pathogenesis of RA in experimental models and in a genetic association study. Experimental arthritis triggered by pristane or collagen type II was induced in DA rats and in the DA.BN-R25 congenic line that carries a polymorphism in Vav1. Difference in arthritis severity was observed only after immunization with pristane. In a case-control study, 34 SNPs from VAV1 locus were analyzed by Immunochip genotyping in 11475 RA patients (7573 anti-CCP positive and 3902 negative) and 15,870 controls in six cohorts of European Caucasians. A combination of the previous MS-associated haplotype and two additional SNPs was associated with anti-CCP negative RA (alleles G-G-A-A of rs682626-rs2546133-rs2617822-rs12979659, OR=1.13, P=1.27 × 10-5). The same markers also contributed to activity of RA at baseline with the strongest association in the anti-CCP negative group for the rs682626-rs12979659 G-A haplotype (β=-0.283, P=0.0048). Our study suggests a role for VAV1 and T-cell signaling in the pathology of anti-CCP-negative RA.

Replication of Associations of Genetic Loci Outside the HLA Region With Susceptibility to Anti-Cyclic Citrullinated Peptide-Negative Rheumatoid Arthritis.

ObjectiveGenetic polymorphisms within the HLA region explain only a modest proportion of anti–cyclic citrullinated peptide (anti‐CCP)–negative rheumatoid arthritis (RA) heritability. However, few non‐HLA markers have been identified so far. This study was undertaken to replicate the associations of anti‐CCP–negative RA with non‐HLA genetic polymorphisms demonstrated in a previous study.Methods The Rheumatoid Arthritis Consortium International densely genotyped 186 autoimmune‐related regions in 3,339 anti‐CCP–negative RA patients and 15,870 controls across 6 different populations using the Illumina ImmunoChip array. We performed a case–control replication study of the anti‐CCP–negative markers with the strongest associations in that discovery study, in an independent cohort of anti‐CCP–negative UK RA patients. Individuals from the arcOGEN Consortium and Wellcome Trust Case Control Consortium were used as controls. Genotyping in cases was performed using Sequenom MassArray technology. Genome‐wide data from controls were imputed using the 1000 Genomes Phase I integrated variant call set release version 3 as a reference panel. Results After genotyping and imputation quality control procedures, data were available for 15 non‐HLA single‐nucleotide polymorphisms in 1,024 cases and 6,348 controls. We confirmed the known markers ANKRD55 (meta‐analysis odds ratio [OR] 0.80; P = 2.8 × 10−13) and BLK (OR 1.13; P = 7.0 × 10−6) and identified new and specific markers of anti‐CCP–negative RA (prolactin [PRL] [OR 1.13; P = 2.1 × 10−6] and NFIA [OR 0.85; P = 2.5 × 10−6]). Neither of these loci is associated with other common, complex autoimmune diseases. Conclusion Anti‐CCP–negative RA and anti‐CCP–positive RA are genetically different disease subsets that only partially share susceptibility factors. Genetic polymorphisms located near the PRL and NFIA genes represent examples of genetic susceptibility factors specific for anti‐CCP–negative RA.

HLA-DRB1 alleles in Egyptian rheumatoid arthritis patients: Relations to anti-cyclic citrullinated peptide antibodies, disease activity and severity

BackgroundHuman leukocyte antigen HLA-DRB1 alleles encoding a common amino acid sequence called shared epitope in the third hypervariable region of DRB1 molecule have been identified as risk alleles for rheumatoid arthritis (RA). Aim of the workThe aim was to study HLA-DRB1 01, 04 and 10 alleles in Egyptian RA patients and determine their relation with anticyclic citrullinated peptide (anti-CCP) antibody level, disease activity, clinical and radiological severity. Patients and methodsThe study involved 40 RA patients and 20 control. Simplified disease activity index (SDAI) was calculated, clinical severity was assessed using the mechanical joint score (MJS) and radiological severity evaluated using the simple erosion narrowing score (SENS). HLA-DRB1 genotyping and anti-CCP antibodies were detected. ResultsThe mean patients’ age was 41.6±12.7years and disease duration 8.9±7.7years. The frequency of HLA DRB1 01, 04 and 10 in patients was 42.5%, 60% and 25% respectively. Of them 04 was significantly higher than in controls (p=0.013) and was associated with anti-CCP positive cases (p=0.0008) while the absence of HLA-DRB1 alleles was significantly associated with negative anti-CCP negative RA (p=0.0008). There were significant associations between HLA-DRB1 01 and 04 with SDAI (p=0.0002 and p=0.005, respectively); between HLA-DRB1 04 and 10 with SENS (p=0.002 and p=0.001 respectively) and between HLA-DRB1 01, 04 and 10 with MJS (p=0.02, p=0.03 and p=0.02, respectively). ConclusionHLA-DRB1 04 is associated with RA in Egyptian patients and is strongly associated in the production of elevated titers of anti-CCP antibodies which contribute to the development, severity and activity of the disease.

Serum levels of anticyclic citrullinated peptide antibodies, interleukin-6, tumor necrosis factor-α, and C-reactive protein are associated with increased carotid intima-media thickness: a cross-sectional analysis of a cohort of rheumatoid arthritis patients without cardiovascular risk factors.

The main cause of death in rheumatoid arthritis (RA) is cardiovascular events. We evaluated the relationship of anticyclic citrullinated peptide (anti-CCP) antibody levels with increased carotid intima-media thickness (cIMT) in RA patients. Methods. Forty-five anti-CCP positive and 37 anti-CCP negative RA patients, and 62 healthy controls (HC) were studied. All groups were assessed for atherogenic index of plasma (AIP) and cIMT. Anti-CCP, C-reactive protein (CRP), and levels of tumor necrosis factor alpha (TNFα) and interleukin-6 (IL-6) were measured by enzyme-linked immunosorbent assay (ELISA). Results. The anti-CCP positive RA patients showed increased cIMT compared to HC and anti-CCP negative (P < 0.001). Anti-CCP positive versus anti-CCP negative RA patients, had increased AIP, TNFα and IL-6 (P < 0.01), and lower levels of high density lipoprotein cholesterol (HDL-c) (P = 0.02). The cIMT correlated with levels of anti-CCP (r = 0.513, P = 0.001), CRP (r = 0.799, P < 0.001), TNFα (r = 0.642, P = 0.001), and IL-6 (r = 0.751, P < 0.001). In multiple regression analysis, cIMT was associated with CRP (P < 0.001) and anti-CCP levels (P = 0.03). Conclusions. Levels of anti-CCP and CRP are associated with increased cIMT and cardiovascular risk supporting a clinical role of the measurement of cIMT in RA in predicting and preventing cardiovascular events.

SAT0164 How Many Patients Followed up with Rheumatoid Arthritis (RA) Diagnosis is Really Ra? 1987 ACR Classification Criteria Compared WİTh 2010 Acr/Eular Criteria for REAL RA PatİEnts in Turkey

BackgroundEarly diagnosis is very important for RA. The 2010 ACR/EULAR RA classification criteria has been mainly developed for this purpose. However, these new criteria may cause RA overdiagnosis.ObjectivesWe aimed to...

SMAD3 rs17228212 Gene Polymorphism Is Associated with Reduced Risk to Cerebrovascular Accidents and Subclinical Atherosclerosis in Anti-CCP Negative Spanish Rheumatoid Arthritis Patients

Rheumatoid arthritis (RA) is a complex polygenic inflammatory disease associated with accelerated atherosclerosis and increased risk of cardiovascular (CV) disease. Previous genome-wide association studies have described SMAD3 rs17228212 polymorphism as an important signal associated with CV events. The aim of the present study was to evaluate for the first time the relationship between this gene polymorphism and the susceptibility to CV manifestations and its potential association with the presence of subclinical atherosclerosis assessed by the evaluation of carotid intima-media thickness (cIMT) in patients with RA.MethodsOne thousand eight hundred and ninety-seven patients fulfilling classification criteria for RA were genotyped for SMAD3 rs17228212 gene polymorphism through TaqMan genotyping assay. Also, subclinical atherosclerosis determined by the assessment of cIMT was analyzed in a subgroup of these patients by carotid ultrasonography.ResultsNo statistically significant differences were observed when allele frequencies of RA patients with or without CV events were compared. Nevertheless, when RA patients were stratified according to anti-cyclic citrullinated peptide (anti-CCP) status, we found that in RA patients who were negative for anti-CCP antibodies, the presence of C allele of SMAD3 rs17228212 polymorphism conferred a protective effect against the risk of cerebrovascular accident (CVA) after adjustment for demographic and classic CV risk factors (HR [95%CI]=0.36 [0.14–0.94], p=0.038) in a Cox regression model. Additionally, correlation between the presence of C allele of SMAD3 rs17228212 polymorphism and lower values of cIMT was found after adjustment for demographic and classic CV risk factors (p-value=0.0094) in the anti-CCP negative RA patients.ConclusionsOur results revealed that SMAD3 rs17228212 gene variant is associated with lower risk of CVA and less severe subclinical atherosclerosis in RA patients negative for anti-CCP antibodies. These findings may have importance to establish predictive models of CV disease in RA patients according to anti-CCP status.

OP0171 Screening for Anti-CCP in a Large Population Based Cohort and its Association with Prevalent Rheumatoid Arthritis

BackgroundAnti-CCP testing is a part of the clinical routine investigations for rheumatoid arthritis (RA). RA has the highest incidence and prevalence at ages 70-80 yrs.ObjectivesWe aimed at investigating the predictive...

Genetic markers of rheumatoid arthritis susceptibility in anti-citrullinated peptide antibody negative patients

IntroductionThere are now over 30 confirmed loci predisposing to rheumatoid arthritis (RA). Studies have been largely undertaken in patients with anticyclic citrullinated peptide (anti-CCP) positive RA, and some genetic associations...

Autoantibodies to BRAF, a new family of autoantibodies associated with rheumatoid arthritis

IntroductionBRAF (v raf murine sarcoma viral oncogene homologue B1) is a serine-threonine kinase involved in the mitogen-activated protein kinase (MAPK) signalling pathway, known to be implicated in the production of pro-inflammatory cytokines.We have observed that sera from rheumatoid arthritis (RA) patients recognize the BRAF's catalytic domain, which encompasses amino acids 416 to 766. Here, we identify peptide targets of anti-BRAF autoantibodies and test whether anti-BRAF autoantibodies may interfere with BRAF kinase activity.MethodsAnti-BRAF autoantibodies were detected by ELISA (enzyme-linked immunosorbent assay) in the serum of RA patients and controls, using 40 overlapping 20mer peptides encompassing the catalytic domain of BRAF as immunosorbents. To test whether autoantibodies to BRAF influence BRAF kinase activity, we developed an in vitro phosphorylation assay of MEK1 (mitogen extracellular regulated kinase), a major BRAF substrate. MEK1 phosphorylation by BRAF was tested in the presence of purified anti-BRAF autoantibodies from RA patients or control antibody.ResultsWe found that one BRAF peptide, P25 (656 to 675), is specifically recognized by autoantibodies from RA patients. Of interest, anti-P25 autoantibodies are detected in 21% of anti-CCP (cyclic citrullinated peptides) negative RA patients. Anti-BRAF autoantibodies activate the in vitro phosphorylation of MEK1 mediated by BRAF.ConclusionsAnti-BRAF autoantibodies from RA patients preferentially recognize one BRAF peptide: P25. Autoantibody responses to P25 are detected in 21% of anti-CCP negative RA patients. Most anti-BRAF autoantibodies activate BRAF kinase activity.

Fc receptor–like 3 gene polymorphisms confer susceptibility to rheumatoid arthritis in a Chinese population

Polymorphisms in the Fc receptor–like 3 (FCRL3) gene have been reported to be associated with rheumatoid arthritis (RA) in Japanese populations. However subsequent studies have yielded conflicting results. Hence the aim of present study was to clarify whether these genetic variants in FCRL3 gene are associated with RA in a Chinese population. We conducted a case-control study of 234 RA patients and 260 controls by genotyping four polymorphisms in FCRL3. The genotype and allele distributions of four polymorphisms were significantly different in RA patients compared with controls (uncorrected p = 0.021 and p = 0.031; 0.027 and 0.008; 0.028 and 0.042; and 0.019 and 0.029, respectively). The FCRL3-169 C allele was significantly associated with rheumatoid factor (RF) and anti–cyclic citrullinated peptide (anti-CCP)–positive RA, but no association was detected for RF and anti-CCP–negative RA. Furthermore, the frequency of the –169C allele was increased disproportionately in female patients, and the resulting odds ratio for female homozygote was increased to 2.375 (uncorrected p = 0.006). Haplotype analysis showed that the most common haplotype TGGG was associated with decreased risk of RA (uncorrected p = 0.001, odds ratio = 0.656). However CACA appeared to be a risk haplotype for RA cases (uncorrected p = 0.031, odds ratio = 1.398). Taken together, these results suggest that FCRL3 polymorphisms and haplotypes may contribute to genetic susceptibility to RA in Chinese population.