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OBJECTIVES: This randomised, double-blind, placebo-controlled phase IIIb study evaluated the impact of abatacept on MRI pathology as a primary outcome in methotrexate (MTX)-refractory patients with rheumatoid arthritis. METHODS: Patients received intravenous abatacept (∼10 mg/kg) or placebo, on background MTX, for 4 months, followed by an 8-month open-label extension (OLE; all patients received abatacept plus MTX). Patients had 1.5T MRI with intravenous contrast at baseline, Months 4 and 12; wrist synovitis (three locations assessed), and wrist and hand (15 and eight locations assessed, respectively) osteitis and erosion were scored using OMERACT-RAMRIS. RESULTS: 26/27 abatacept- and 23/23 placebo-randomised patients completed Month 4 and entered the OLE; 26 and 21 completed Month 12. The primary endpoint was not achieved; mean change (SD) from baseline in synovitis was -0.44 (1.47) for abatacept versus 0.52 (1.38) for placebo (p=0.103) at Month 4. For mean change in synovitis adjusted for baseline score (sensitivity analysis), the difference between groups was -0.69, p=0.078. Adjusted mean changes (SE) in osteitis and erosion were -1.94 (0.86) and 0.45 (0.43) for abatacept, and 1.54 (0.90) and 0.95 (0.45) for placebo. Further MRI improvements were observed up to Month 12 for abatacept and from Months 4 to 12 for placebo-treated patients switched to abatacept at Month 4. Clinical efficacy was shown with abatacept and sustained to Month 12. CONCLUSIONS: Despite small patient numbers, MRI detected structural and synovial benefit, sustained to Month 12 in abatacept+MTX-treated patients, and improvements in structural and inflammatory outcomes for placebo+MTX-treated patients following addition of abatacept. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov NCT00420199.

Objectives Lung exposures including cigarette smoking and silica exposure are associated with the risk of rheumatoid arthritis (RA). We investigated the association between textile dust exposure and the risk of RA in the Malaysian population, with a focus on women who rarely smoke. Methods Data from the Malaysian Epidemiological Investigation of Rheumatoid Arthritis (MyEIRA) population-based case-control study involving 910 female early RA cases and 910 female age-matched controls were analysed. Self-reported information on ever/never occupationally exposed to textile dust was used to estimate the risk of developing anti-citrullinated protein antibody (ACPA)-positive and ACPA-negative RA. Interaction between textile dust and the HLA-DRB1 shared epitope (SE) was evaluated by calculating the attributable proportion due to interaction (AP), with 95% CI. Results Occupational exposure to textile dust was significantly associated with an increased risk of developing RA in the Malaysian female population (OR 2.8, 95% CI: 1.6–5.2). The association between occupational exposure to textile dust and risk of RA was uniformly observed for the ACPA-positive RA (OR 2.5, 95% CI: 1.3–4.8) and ACPA-negative RA (OR 3.5, 95% CI: 1.7–7.0) subsets, respectively. We observed a significant interaction between exposure to occupational textile dust and HLA-DRB1 SE alleles regarding the risk of ACPA-positive RA (OR for double exposed: 39.1, 95% CI: 5.1–297.5; AP: 0.8, 95% CI: 0.5–1.2). Conclusions This is the first study demonstrating that textile dust exposure is associated with an increased risk for RA. In addition a gene-environment interaction between HLA-DRB1 SE and textile dust exposure provides a high risk for ACPA-positive RA.

There is growing evidence of shared risk alleles for complex traits (pleiotropy), including autoimmune and neuropsychiatric diseases. This might be due to sharing among all individuals (whole-group pleiotropy) or a subset of individuals in a genetically heterogeneous cohort (subgroup heterogeneity). Here we describe the use of a well-powered statistic, BUHMBOX, to distinguish between those two situations using genotype data. We observed a shared genetic basis for 11 autoimmune diseases and type 1 diabetes (T1D; P1 × 10(-4)) and for 11 autoimmune diseases and rheumatoid arthritis (RA; P1 × 10(-3)). This sharing was not explained by subgroup heterogeneity (corrected PBUHMBOX0.2; 6,670 T1D cases and 7,279 RA cases). Genetic sharing between seronegative and seropostive RA (P1 × 10(-9)) had significant evidence of subgroup heterogeneity, suggesting a subgroup of seropositive-like cases within seronegative cases (PBUHMBOX = 0.008; 2,406 seronegative RA cases). We also observed a shared genetic basis for major depressive disorder (MDD) and schizophrenia (P1 × 10(-4)) that was not explained by subgroup heterogeneity (PBUHMBOX = 0.28; 9,238 MDD cases).

Objective High titers of specific anti–citrullinated protein antibodies (ACPAs) are frequently present in the serum of rheumatoid arthritis (RA) patients, but their presence in synovial fluid is less well characterized. The purpose of this study was to compare the levels of antibody to 4 well-defined citrullinated candidate RA autoantigens in serum and synovial fluid and to determine whether antibodies to one citrullinated antigen are dominant over another. Furthermore, we studied their relationships with mutated citrullinated vimentin (MCV), a newly identified RA-specific serum assay, and the classic cyclic citrullinated peptide (CCP) in the synovial fluid of well-defined HLA–DR groups. Methods Paired serum and synovial fluid samples from 290 RA patients and serum samples from 100 age- and sex-matched healthy controls were analyzed for the presence of anti-MCV and anti-CCP antibodies and for reactivity to citrullinated fibrinogen, α-enolase, type II collagen, and vimentin. A total of 219 of the 290 patients were genotyped for the HLA–DR shared epitope alleles. Results Significantly higher proportions of antibodies against all RA-associated citrullinated antigens were found in synovial fluid as compared with serum. This was also true for the MCV and CCP responses but not for non–RA-associated anti–tetanus toxoid antibodies. As expected, we found a high correlation between citrullinated vimentin and MCV responses. All synovial fluid ACPAs were predominantly associated with HLA–DRB1*04 alleles and were confined to the CCP+/MCV+ subset of patients. Conclusion MCV and CCP positivity represent a similar subset of RA patients, whereas ACPAs with different fine specificities fall into subgroups of anti-CCP+/anti-MCV+ patients. The levels of all specific ACPAs were elevated in synovial fluid, suggesting that there is local antibody production and/or retention of ACPAs at the site of inflammation governed by RA-predisposing genes.

A monoclonal antibody reactive with the mycobacterial 65 kDa heal shock protein (ML 30) was investigated for reactivity with biopsies from normal rat joints and with inflamed joints due to adjuvant arthritis (AA) or collagen induced arthrilis (CIA). Immunohistochemical stainings with the ant-hsp 65 antibody on paralVm sections from normal rat joints revealed a weak but exclusive staining of cells within the synovial lining. Also normal chondrocytes and bone marrow cells showed oceasioniil staining. In biopsies from inflamed joints obtained from rats suffering from AA or CIA. an intense staining with ML 30 was seen with in the Ciirtilage-pannus junction as well as sites of bone erosion. An increased staining, compared with the normal, was also seen in chondroeytes of the eroded cartilage and in some bone marrow cells. No staining with ML 30 was seen in biopsies from inflammatory lesions due to delayed type hyperscnsitivity reactions in the skin of rats. Reactivity of ML 30 was also seen in a Western blot assay performed on lysates from inflamed synovia from rats with CIA, preferentially with a component slightly below 60 kDa in molecular weight. The demonstration of epitopes cross-reactive with hsp 65 of mycobacteria in normal and. in higher quantity, in arthritic rat joints, suggests, together with our preliminary biochemical findings, that a recently identified mammalian counterpart to bacterial hsp 65 is both preferentially expressed in normal joints and subject to increased expression in arthritis of different aetiologies.

Multiple sclerosis, the most common cause of progressive neurological disability in young adults, is a chronic inflammatory disease. There is solid evidence for a genetic influence in multiple sclerosis, and deciphering the causative genes could reveal key pathways influencing the disease. A genome region on rat chromosome 9 regulates experimental autoimmune encephalomyelitis, a model for multiple sclerosis. Using interval-specific congenic rat lines and association of single-nucleotide polymorphisms with inflammatory phenotypes, we localized the gene of influence to Vav1 , which codes for a signal-transducing protein in leukocytes. Analysis of seven human cohorts (12,735 individuals) demonstrated an association of rs2546133-rs2617822 haplotypes in the first VAV1 intron with multiple sclerosis (CA: odds ratio, 1.18; CG: odds ratio, 0.86; TG: odds ratio, 0.90). The risk CA haplotype also predisposed for higher VAV1 messenger RNA expression. VAV1 expression was increased in individuals with multiple sclerosis and correlated with tumor necrosis factor and interferon-γ expression in peripheral blood and cerebrospinal fluid cells. We conclude that VAV1 plays a central role in controlling central nervous system immune-mediated disease and proinflammatory cytokine production critical for disease pathogenesis.

Summary Objective To explore the possibility of cartilage protection in osteoarthritis (OA) by intraarticular injection of a chemically modified hyaluronan (HA) gel and investigate whether the chemical modifications provide intrinsic anti-inflammatory activity. Method OA was induced in C57BL/6 mice by anterior cruciate ligament transection (ACLT) and HA gel or carbazate-modified component was injected intra-articularly. Assessment of cartilage rescue was performed by histology, immunohistochemistry and TUNEL analysis. Serum levels of proinflammatory cytokines were evaluated with cytometric bead array, measuring IL-1β, TNF, IFN-γ, KC/CXCL1 and MCP-1. Results Intraarticular injection of the HA gel showed significantly reduced cartilage destruction and decreased osteophyte formation. Besides the biological and biomechanical effects of HA, we investigated lipid peroxidation products as an alternative inflammatory and potential mechanism contributing to OA. To address this, injection of the carbazate-modified component alone was performed, which also demonstrated a cartilage-saving effect. Besides the cartilage amelioration effects, decreased apoptosis, 4-hydroxynonenal (4-HNE) and MHC class II staining was recorded. No changes in serum levels of proinflammatory cytokines were detected. Conclusion We have shown that the HA gel has an anti-destructive effect on articular cartilage (AC). Our results demonstrated that the carbazate-modified component could suppress apoptotic events, potentially by quenching of ROS/LPO products such as 4-HNE in OA joints. Modification of the HA molecule offers opportunities to introduce (covalent) coupling of additional molecules to the gel, with controlled retention and subsequent release in the joint.

Objective To determine the relationship between changes in antibody levels towards citrullinated peptides derived from different candidate autoantigens and therapeutic outcome in early rheumatoid arthritis (RA). Methods Baseline and 3-month serum samples from 316 patients with early RA enrolled in the Swedish Farmacotherapy (SWEFOT) trial were analysed for antibodies against cyclic citrullinated peptides (CCP) and citrullinated peptides derived from vimentin (cVim), fibrinogen (cFib) and a-enolase (CEP-1). At 3-month follow-up, methotrexate monotherapy-inadequate responders were randomised to add-on therapy with sulfasalazine and hydroxychloroquine or infliximab. In these patients, anticitrullinated peptide antibodies (ACPA) were also assessed at 12 and 24 months. The proportion of antibody-positive patients and relative changes in antibody levels were compared across ACPA specificities and related to therapeutic response and radiographic progression. Results During the 2-year follow-up, the proportion of patients testing positive declined significantly regarding antibodies to cVim, cFib and CEP-1, while anti-CCP antibody occurrence remained stable over time. Turning anti-cVim antibody negative was most common, and anti-cVim antibody seroreversion during the first three months associated with significantly less 2-year radiographic progression compared with patients who remained positive. Median antibody levels of all tested ACPAs declined uniformly during initial methotrexate therapy and following response to add-on therapy, with no significant relation to treatment regimen or radiographic progression. Conclusions The influence of early antirheumatic therapy on ACPA seroreversions was markedly different across specificities, and early disappearance of anti-cVim antibodies associated with better radiological outcome. Thus, these data suggest that the disappearance of particular ACPA reactivities may be beneficial in early RA. Funding Agencies|EU [FP7-Health-2010-261460, FP7-Health-2013-306029]; County Council of Ostergotland; Reinhold Sund Foundation; Swedish Society of Medicine; Swedish Rheumatism Association; Thelma Zoegas foundation in Helsingborg; Stiftelsen for Rorelsehindrade i Skane; Swedish Research Council; Strategic Foundations of Sweden (SSF)

Background The presence of rheumatoid factor (RF), anti-carbamylated protein antibodies (anti-CarP) and antibodies against citrullinated protein and peptides (ACPA) precedes the onset of symptoms of rheumatoid arthritis (RA) by several years. Relationships between the development of these antibodies are not obvious. Methods Three isotypes [immunoglobulin A (IgA), IgG and IgM) of RF were analysed in 321 pre-symptomatic individuals who provided 598 samples collected a median of 6.2 (interquartile range 7.2) years before the onset of symptoms, and in 492 population control subjects. All samples were donated to the Biobank of Northern Sweden. RF isotypes were analysed using the EliA system (Phadia GmbH, Freiburg, Germany) with 96 % specificity according to receiver operating characteristic curves. Ten ACPA specificities were analysed using the ImmunoCAP ISAC system, and anti-CCP2 and anti-CarP antibodies were evaluated using enzyme-linked immunosorbent assays. Results The frequencies of RF isotypes in pre-symptomatic individuals were significantly increased compared with control subjects (p

Objective.STAT3 and 4 are, among other factors, critical for the interleukin 12 (IL-12)-mediated Th1 response, for transfer of IL-23 signals, and for survival and expansion of Th17 cells. We investigated the association of STAT3 and STAT4 polymorphisms with serologically distinct subgroups of rheumatoid arthritis (RA).Methods.A total of 41 single-nucleotide polymorphisms (SNP) within STAT3 and STAT1-STAT4 loci were investigated in a Swedish cohort of 2043 RA cases and 1115 controls. Nine of the associated SNP were tested in a Spanish cohort of 1223 RA cases and 1090 controls.Results.Fourteen SNP in the STAT3 and STAT1-STAT4 loci were associated with anticitrullinated protein antibody (ACPA)-negative RA in the Swedish cohort. Three of the SNP inSTAT4and 2 SNP inSTAT3remained associated with ACPA-negative RA after considering the Spanish results. In addition, rs7574865 and rs10181656, inSTAT4, were associated with ACPA-positive RA in the Swedish study. One of these SNP, rs7574865, showed a similar pattern of the association in serologically distinct subgroups of RA in a metaanalysis of all 7 published studies.Conclusion.Our findings suggest that variants in STAT genes may contribute differentially to susceptibility to RA in seropositive and in seronegative patients.

Objective Production of anti–citrullinated protein antibodies (ACPAs) is an important biomarker for rheumatoid arthritis (RA). We undertook this study to determine whether genetic factors (HLA—DRB1 alleles) are associated with extreme ACPA levels in individuals with ACPA-positive RA, and to ascertain whether there are any phenotypic characteristics associated with these subgroups of RA. Methods HLA–DRB1 allelic groups were genotyped in 1,073 ACPA-positive RA patients from the Swedish Epidemiological Investigation of Rheumatoid Arthritis study. We found that 283 patients (26.4%) had high ACPA levels (defined as >1,500 units/ml using the Euro-Diagnostica anti-CCP2 test), while the rest of the patients had moderate ACPA levels and served as the comparison group. A replication group consisted of 235 RA patients. Results No significant differences in baseline disease activity were observed between patients with high and those with moderate ACPA levels. However, the HLA–DRB1*15 allele was associated with high ACPA levels (P = 0.0002). A similar trend was detected in HLA–DRB1*15–positive patients in the replication cohort, with meta-analysis of the discovery and replication cohorts demonstrating an overall effect of HLA–DRB1*15 on development of high ACPA levels in both the discovery and replication cohorts (P < 0.0001 by Mantel-Haenszel test with a fixed-effects model). Conclusion Our data indicate that HLA–DRB1*15 may promote the production of high ACPA levels. Due to the high value of ACPA level scores in the 2010 American College of Rheumatology/European League Against Rheumatism classification criteria for RA, the presence of HLA–DRB1*15 may, at least in part, contribute to fulfilling the criteria for RA. This illustrates the complex nature of the genetic regulation of ACPA levels. Additional mechanistic studies of the regulation of ACPAs and ACPA-positive RA are pending.

Objectives To increase understanding of the aetiology and pathogenesis of rheumatoid arthritis (RA), genetic and environmental risk factors for RA subsets, defi ned by the presence or absence of different anticitrullinated protein/peptide antibodies (ACPAs) targeting citrullinated peptides from α-enolase, vimentin, fi brinogen and collagen type II, were investigated. Methods 1985 patients with RA and 2252 matched controls from the EIRA case-control cohort were used in the study. Serum samples were assayed by ELISA for the presence of anticyclic citrullinated peptides (antiCCP) antibodies and four different ACPA fi ne specifi cities. Cross-reactivity between ACPAs was examined by peptide absorption experiments. Genotyping was performed for HLA-DRB1 shared epitope (SE) alleles and the PTPN22 gene, while information regarding smoking was obtained by questionnaire. The association of genetic and environmental risk factors with different subsets of RA was calculated by logistic regression analysis. Results Limited cross-reactivity was observed between different ACPA fi ne specifi cities. In total, 17 RA subsets could be identifi ed based on their different ACPA fi ne specifi city profi les. Large differences in association with genetic and environmental determinants were observed between subsets. The strongest association of HLA-DRB1 SE, PTPN22 and smoking was identifi ed for the RA subset which was defi ned by the presence of antibodies to citrullinated α-enolase and vimentin. Conclusion This study provides the most comprehensive picture to date of how HLA-DRB1 SE, PTPN22 and smoking are associated with the presence of specifi c ACPA reactivities rather than anti-CCP levels. The new data will form a basis for molecular studies aimed at understanding disease development in serologically distinct subsets of RA.

Objective. Antibodies against citrullinated type II collagen (Cit-CII) are common in the sera and synovial fluid of patients with rheumatoid arthritis (RA); however, the known T cell epitope of CII is not dependent on citrullination. The aim of this study was to identify and functionally characterize the Cit-CII-restricted T cell epitopes that are relevant to RA. Methods. Peripheral blood mononuclear cells (PBMCs) from HLA-DRB1*10:01-positive patients with RA and healthy donors were stimulated in vitro with candidate CII peptides. CD154 up-regulation was measured as a marker of antigen-specific activation, and anti-HLA-DR-blocking experiments confirmed HLA restriction. Cytokine production was measured using a Luminex technique. Direct peptide-binding assays using HLA-DRB1*10:01 and HLA-DRB1*04:01 monomeric proteins were performed. The T cell receptor (TCR) beta-chain of CD154-enriched antigen-specific T cells was analyzed using high-throughput sequencing. Results. A novel Cit-CII peptide was identified based on its ability to activate CD4+ T cells from HLA-DRB1*10:01-positive individuals. When stimulated in vitro, Cit-CII autoreactive T cells produced proinflammatory cytokines. Cit-CII311-325 bound (with low affinity) to HLA-DRB1*10:01 but not to HLA-DRB1*04:01, while the native form was unable to bind either protein. In addition, highly expanded clones were identified in the TCR beta repertoire of Cit-CII311-325-stimulated PBMCs. Conclusion. These results illustrate the ability of the citrullination process to create T cell epitopes from CII, a cartilage-restricted protein that is relevant to RA pathogenesis. The exclusive binding of Cit-CII311-325 to HLA-DRB1*10:01 suggests that recognition of citrullinated epitopes might vary between individuals carrying different RA-associated HLA-DR molecules.

Background: In women with rheumatoid arthritis (RA) it has been observed that during pregnancy a majority of patients experience amelioration, but after delivery a relapse of the disease is common. However, there are few studies, with diverging results, addressing the effect of parity on the severity of RA over time. Our aim was to explore the impact of parity, with stratification for anti-citrullinated protein antibody (ACPA) status as well as for onset during reproductive age or not. Methods: Female RA cases aged 18-70 years were recruited for the Epidemiological Investigation of Rheumatoid Arthritis (EIRA). Information on disease severity (the health assessment questionnaire (HAQ) and the disease activity score 28 (DAS28)) was retrieved from the Swedish Rheumatology Quality Register at inclusion and 3, 6, 12 and 24 months after diagnosis. Mixed models were used to compare mean DAS28 and HAQ scores over time in parous and nulliparous women. Mean differences at individual follow-up visits were compared using analysis of covariance. The odds of having DAS28 or HAQ above the median in parous verus nulliparous women were estimated in logistic regression models. Results: A total of 1237 female cases (mean age 51 years, 65 % ACPA-positive) were included. ACPA-negative parous women, aged 18-44 years, had on average 1.17 units higher DAS28 (p < 0.001) and 0.43 units higher HAQ score (p < 0.001) compared to nulliparous women during the follow-up time, adjusted for age. In this subgroup, the average DAS28 and HAQ scores were significantly higher in parous women at all follow-up time points. Younger parous ACPA-negative women were significantly more likely to have DAS28 and HAQ values above the median compared to nulliparous women at all follow-up visits. No association between parity and severity of ACPA-positive disease was observed. Conclusions: Parity was a predictor of a more severe RA among ACPA-negative younger women, which might indicate that immunomodulatory changes during and after pregnancy affect RA severity, in particular for the ACPA-negative RA phenotype.

Shared genetic architecture between phenotypes may be driven by a common genetic basis (pleiotropy) or a subset of genetically similar individuals (heterogeneity). We developed BUHMBOX, a well-powered statistical method to distinguish pleiotropy from heterogeneity using genotype data. We observed a shared genetic basis between 11 of 17 tested autoimmune diseases and type I diabetes (T1D, p0.2 using 6,670 T1D cases and 7,279 RA cases), suggesting that shared genetic features in autoimmunity are due to pleiotropy. We observed a shared genetic basis between seronegative and seropostive RA (p

We investigated the association between cigarette smoking and the risk of developing rheumatoid arthritis (RA) in the Malaysian population. A total of 1,056 RA patients and 1,416 matched controls aged 18–70 years within a defined area of Peninsular Malaysia were evaluated in a case–control study between August 2005 and December 2009. A case was defined as a person with early diagnosed RA using the 1987 American College of Rheumatology criteria for RA. Controls were randomly selected matched for sex, age, and residential area. Cases and controls answered a questionnaire on a broad range of issues, including lifestyle factors and smoking habits wherein current and former smoking was classified as ever-smoking. The presence of anti-citrullinated peptide antibodies (ACPA) was determined for cases and controls. We found that ever-smokers had an increased risk of developing ACPA-positive RA [odds ratio (OR) = 4.1, 95% confidence interval (CI) 1.9–9.2] but not ACPA-negative RA (OR = 0.7, 95% CI 0.3–2.0), compared with never-smokers. A significant dose–response relationship between cumulative dose of smoking and risk of ACPA-positive RA was observed (

LMO2 protein expression predicts survival in patients with rheumatoid arthritis and diffuse large B-cell lymphoma

BackgroundEarlier studies have demonstrated that smoking and genetic risk factors interact in providing an increased risk of rheumatoid arthritis (RA). Less is known on how smoking contributes to RA in the context of genetic variability, and what proportion of RA may be caused by smoking.ObjectivesTo determine the association between the amount of smoking and risk of RA in the context of different HLA-DRB1 shared epitope (SE) alleles, and to estimate proportions of RA cases attributed to smoking.Design, Setting and ParticipantsData from the Swedish Epidemiological Investigation of Rheumatoid Arthritis (EIRA) case–control study encompassing 1204 cases and 871 controls were analysed.Main OutcomeMeasure Estimated OR to develop RA and excess fraction of cases attributable to smoking according to the amount of smoking and genotype.ResultsSmoking was estimated to be responsible for 35% of anticitrullinated protein/peptide antibody (ACPA)-positive cases. For each HLA-DRB1 SE genotype, smoking was dose-dependently associated with an increased risk of ACPA-positive RA (p trend ConclusionsSmoking is a preventable risk factor for RA. The increased risk due to smoking is dependent on the amount of smoking and genotype.

Psoriatic arthritis (PsA) is an inflammatory joint disease that is distinct from other chronic arthritides and which is frequently accompanied by psoriasis vulgaris (PsV) and seronegativity for rheumatoid factor. We conducted a genome-wide association study in 609 German individuals with PsA (cases) and 990 controls with replication in 6 European cohorts including a total of 5,488 individuals. We replicated PsA associations at HLA-C and IL12B and identified a new association at TRAF3IP2 (rs13190932, P = 8.56 × 10⁻¹⁷). TRAF3IP2 was also associated with PsV in a German cohort including 2,040 individuals (rs13190932, P = 1.95 × 10⁻³). Sequencing of the exons of TRAF3IP2 identified a coding variant (p.Asp10Asn, rs33980500) as the most significantly associated SNP (P = 1.13 × 10⁻²⁰, odds ratio = 1.95). Functional assays showed reduced binding of this TRAF3IP2 variant to TRAF6, suggesting altered modulation of immunoregulatory signals through altered TRAF interactions as a new and shared pathway for PsA and PsV.

To understand the genetic predisposition to selective immunoglobulin A deficiency (IgAD), we performed a genome-wide association study in 430 affected individuals (cases) from Sweden and Iceland and 1,090 ethnically matched controls, and we performed replication studies in two independent European cohorts. In addition to the known association of HLA with IgAD, we identified association with a nonsynonymous variant in IFIH1 (rs1990760GA, P = 7.3 x 10(-10)) which was previously associated with type 1 diabetes and systemic lupus erythematosus. Variants in CLEC16A, another known autoimmunity locus, showed suggestive evidence for association (rs6498142CG, P = 1.8 x 10(-7)), and 29 additional loci were identified with P5 x 10(-5). A survey in IgAD of 118 validated non-HLA autoimmunity loci indicated a significant enrichment for association with autoimmunity loci as compared to non-autoimmunity loci (P = 9.0 x 10(-4)) or random SNPs across the genome (P0.0001). These findings support the hypothesis that autoimmune mechanisms may contribute to the pathogenesis of IgAD.

Holmqvist ME, Wedren S, Jacobsson LTH, Klareskog L, Nyberg F, Rantapaa-Dahlqvist S, Alfredsson L, Askling J (Institute of Environmental Medicine, Karolinska Institutet, Stockholm; Karolinska Institutet/Karolinska Hospital, Stockholm; Malmo University Hospital, Malmo; AstraZeneca RD and Umea University Hospital, Umea, Sweden) Rapid increase in myocardial infarction risk following diagnosis of rheumatoid arthritis amongst patients diagnosed between 1995 and 2006. J Intern Med 2010; 268: 578-585. The risk of ischaemic heart disease (IHD), and in particular myocardial infarction (MI), is increased amongst patients with established rheumatoid arthritis (RA). Few studies have included contemporary patients with RA. We recently reported that the risk of IHD is not elevated before the onset of RA symptoms. However, when, in relation to RA diagnosis, the risk is increased is unknown. Objective. To assess the risk of MI and other IHD events amongst patients diagnosed with RA during the last decade and within 18 months following RA symptom onset, compared to the general population, by time since RA diagnosis, year of RA diagnosis and by rheumatoid factor (RF) status. Methods and patients. A Swedish inception cohort of RA (n = 7469) diagnosed between 1995 and 2006 and a matched general population comparator cohort (n = 37 024), was identified and linked to national registers of morbidity and mortality from IHD. Relative risks (RRs) of MI and other IHD events were estimated using Cox regression. Results. During follow-up, 233 patients with RA and 701 controls developed a first MI, corresponding to an overall RR of MI of 1.6 (95% confidence interval 1.4, 1.9). Increased risks of MI were already detected within 1-4 years following RA diagnosis, as well as in patients diagnosed with RA during the last 5 years, in RF-negative patients and for transmural as well as nontransmural MIs. Conclusions. MI risk increases rapidly following RA diagnosis, suggesting the importance of additional mechanisms other than atherosclerosis. The elevated short-term risk is present amongst patients diagnosed in recent years, underscoring the importance of MI prevention from the time of RA diagnosis.

Exposure to certain environmental factors within genetically predisposed individuals is thought to be an underlying cause of the development of rheumatoid arthritis (RA), a complex autoimmune disease affecting approximately 1% of the adult population (1). Epidemiological research has suggested cigarette smoking as a strong environmental risk factor for RA (2-5). Evidence of dose effects for both smoking and the gene-environmental effects of smoking have been demonstrated within the Nurses' Health Study (2, 6). Genetic variants associated with increased risk of RA within the Human Leukocyte Antigen (HLA) complex have been known for decades (7, 8) and numerous studies have shown strong gene-environment interactions between HLA and smoking (3, 6, 9-12). Glutathione S-transferase (GST) genes are a widely expressed supergene family encoding biotransforming enzymes that catalyze the conjugation of glutathione and are involved in the detoxification of cytotoxic carcinogens and metabolites. GST substrates found in cigarette smoke include α- and β-unsaturated carbonyls, polycyclic aromatic hydrocarbons and reactive oxygen species (ROS), which may lead to cellular damage through oxidative stress. Variations in these genes reduce glutathione conjugation and therefore may increase susceptibility to the harmful effects of carcinogen exposure and oxidative stress (13-19). Polymorphisms within the GST Mu (GSTM1), Theta (GSTT1) and Pi (GSTP1) classes have been identified. Individuals with homozygous deletions at the GSTM1 and GSTT1 loci (GSTM1-null and GSTT1-null) have no functional enzymatic activity (13-19). In GSTP1, an A to G single nucleotide polymorphism (SNP) may result in reduced enzymatic activity for AG and GG genotypes when compared to AA (18, 20, 21). Numerous studies have examined the possible associations between GST polymorphisms and disease risk or disease phenotype determination. It has been hypothesized that GST variations are associated with susceptibility in various cancers (22, 23), most notably lung cancer (17-19). Previous studies have shown relationships between GSTT1-null or GSTM1 polymorphisms and RA risk and severity, but have reported inconsistent interactions between the GSTs and smoking (3, 24-27). Significant GST-smoking interactions have been discovered (3, 16, 17, 22), suggesting that underlying environmental exposures play an important role in the effect of GST genotypes. Heme Oxygenase-1 (HMOX1), the inducible form of heme oxygenase, catabolizes heme groups into biliverdin, free iron, and carbon monoxide. HMOX1 has been shown to have anti-oxidant, anti-inflammatory and cytoprotective properties and to be up-regulated under the presence of nicotine (28-32). An A to T SNP that may affect the level of an HMOX1 production response has been identified; subjects with TA or TT genotypes have lower HMOX1 expression when compared to those with the AA genotype (31). Previous research has studied the associations between HMOX1 and several diseases (31, 32), including lung cancer (33). Recent studies have identified a role for HMOX1 enzymes in RA biology (34) and associations between HMOX1 polymorphisms and RA susceptibility and severity (35, 36). Our study focuses on three genetic polymorphisms within the GST Mu (GSTM1-null), Theta (GSTT1-null) and Pi (rs1695) classes and one polymorphism within the HMOX1 gene promoter (rs2071716). We hypothesized that significant gene-environment interactions exist between these genetic variations and heavy smoking because of the failure to detoxify cigarette smoking and studied the effect of these interactions on the risk of all RA and serologic RA phenotypes. We further hypothesized that interactions would be stronger for seropositive RA.

BACKGROUND: Genetic factors have a substantial role in determining development of rheumatoid arthritis (RA), and are likely to account for 50-60% of disease susceptibility. Genome-wide association studies have identified non-human leucocyte antigen RA susceptibility loci which associate with RA with low-to-moderate risk.OBJECTIVES: To investigate recently identified RA susceptibility markers using cohorts from six European countries, and perform a meta-analysis including previously published results.METHODS: 3311 DNA samples were collected from patients from six countries (UK, Germany, France, Greece, Sweden and Denmark). Genotype data or DNA samples for 3709 controls were collected from four countries (not Sweden or Denmark). Eighteen single nucleotide polymorphisms (SNPs) were genotyped using Sequenom MassArray technology. Samples with a >95% success rate and only those SNPs with a genotype success rate of >95% were included in the analysis. Scandinavian patient data were pooled and previously published Swedish control data were accessed as a comparison group. Meta-analysis was used to combine results from this study with all previously published data.RESULTS: After quality control, 3209 patients and 3692 controls were included in the study. Eight markers (ie, rs1160542 (AFF3), rs1678542 (KIF5A), rs2476601 (PTPN22), rs3087243 (CTLA4), rs4810485 (CD40), rs5029937 (6q23), rs10760130 (TRAF1/C5) and rs7574865 (STAT4)) were significantly associated with RA by meta-analysis. All 18 markers were associated with RA when previously published studies were incorporated in the analysis. Data from this study increased the significance for association with RA and nine markers.CONCLUSIONS: In a large European RA cohort further evidence for the association of 18 markers with RA development has been obtained.

ObjectiveTo evaluate the efficacy and safety of golimumab to 52 weeks in patients with active rheumatoid arthritis despite methotrexate.MethodsPatients were randomly assigned to receive placebo plus methotrexate (group 1), golimumab 100 mg plus placebo (group 2), golimumab 50 mg plus methotrexate (group 3) and golimumab 100 mg plus methotrexate (group 4). At week 16, patients in groups 1, 2 and 3 who had less than 20% improvement in tender and swollen joints entered early escape. At week 24, patients in group 1 who had not entered early escape crossed over to 50 mg golimumab plus methotrexate.ResultsAt week 16, 31%, 27% and 17% of patients in groups 1, 2 and 3, respectively, entered early escape. At week 52, 44%, 45%, 64% and 58% of patients in groups 1, 2, 3 and 4, respectively, achieved 20% improvement in the American College of Rheumatology criteria; and 34%, 31%, 42% and 53%, respectively, achieved low disease activity (≤3.2) according to the 28-joint disease activity score. Patients in group 4 appeared to have an increased risk of serious adverse events and serious infections.ConclusionThe results of various outcome measures showed that the response rates achieved by patients receiving golimumab to 24 weeks were sustained to 52 weeks. The safety profile appeared to be consistent with the known safety profile of tumour necrosis factor inhibitors.

BackgroundRecent discoveries of risk alleles have made it possible to define genetic risk profiles for patients with rheumatoid arthritis (RA). This study examined whether a cumulative score based on 22 validated genetic risk alleles for seropositive RA would identify high-risk, asymptomatic individuals who might benefit from preventive interventions.MethodsEight human leucocyte antigen (HLA) alleles and 14 single-nucleotide polymorphisms representing 13 validated RA risk loci were genotyped among 289 white seropositive cases and 481 controls from the US Nurses' Health Studies (NHS) and 629 white cyclic-citrullinated peptide antibody-positive cases and 623 controls from the Swedish Epidemiologic Investigation of Rheumatoid Arthritis (EIRA). A weighted genetic risk score (GRS) was created, in which the weight for each risk allele is the log of the published odds ratio (OR). Logistic regression was used to study associations with incident RA. Area under the curve (AUC) statistics were compared from a clinical-only model and clinical plus genetic model in each cohort.ResultsPatients with GRS >1.25 SD of the mean had a significantly higher OR of seropositive RA in both NHS (OR=2.9, 95%CI 1.8 to 4.6) and EIRA (OR 3.4, 95% CI 2.3 to 5.0) referent to the population average. In NHS, the AUC for a clinical model was 0.57 and for a clinical plus genetic model was 0.66, and in EIRA was 0.63 and 0.75, respectively.ConclusionThe combination of 22 risk alleles into a weighted GRS significantly stratifies individuals for RA risk beyond clinical risk factors alone. Given the low incidence of RA, the clinical utility of a weighted GRS is limited in the general population.

An association between periodontitis and rheumatoid arthritis (RA) has been proposed based on observations of increased risk of periodontitis in patients with RA as well as the presence of antibodies to citrullinated protein antigens (ACPAs) and rheumatoid factor (RF) in serum and gingiva of patients with periodontitis.1–3 Additionally, smoking is one of the most important risk factors for both periodontitis and RA, and predispose for the development of seropositive RA.4–6 We have previously reported that smokers with RA have increased prevalence of periodontitis as compared with never smokers in the Swedish population-based case–control study EIRA (Epidemiological Investigation of Rheumatoid Arthritis).7 The objective of the current study was to further investigate the effects of smoking on the risk of periodontitis in seropositive and seronegative (ACPA/RF) subsets of RA. Data on periodontal status (years 2008–2012) were retrieved from the Swedish Dental Health Registry (DHR) for 2327 patients with established RA (1469/852 ACPA-positive/ACPA-negative and 1505/822 RF-positive/RF-negative, respectively) included in the EIRA study (years 1996–2009) as previously described.7 Periodontal diagnosis was based on diagnostic codes for periodontitis, peri-implantitis and …

OBJECTIVE: To investigate the relative importance of shared etiologies for rheumatoid arthritis (RA) and ischemic heart disease (IHD) in terms of the well-known increased risk of IHD in patients with RA, by assessing the occurrence of IHD up until the time of the onset of the first symptoms of RA. METHODS: We assessed the prevalence of a history of IHD, myocardial infarction (MI), and angina pectoris before the onset of RA symptoms in 2 large population-based case-control studies. Patients with newly diagnosed RA according to the criteria of the American College of Rheumatology were included as cases. We used data from the Swedish Early Arthritis Register study and the Swedish Epidemiologic Investigation of Rheumatoid Arthritis case-control study and from general population controls. Information on IHD, MI, and angina pectoris was obtained from the nationwide Hospital Discharge Register and from self reports. We calculated odds ratios (ORs) and 95% confidence intervals (95% CIs) to compare the prevalence of a history of IHD/MI/angina pectoris among patients with RA with that among population controls. RESULTS: We could not detect any increased occurrence of IHD, MI, or angina pectoris before the onset of symptoms of RA, regardless of whether data on IHD were obtained from the Hospital Discharge Register or were self reported. As detected in the Hospital Discharge Register, the OR for IHD overall was 1.0 (95% CI 0.9-1.1), the OR for MI was 1.0 (95% CI 0.9-1.1), and the OR for angina pectoris was 1.0 (95% CI 0.9-1.2). CONCLUSION: Shared risk factors or susceptibilities for RA and IHD are likely to contribute less than RA-related factors to the increased occurrence of IHD in patients with manifest RA. Nonetheless, the existence of shared factors associated with longer latency until the occurrence of IHD cannot be excluded.

The definition of European population genetic substructure and its application to understanding complex phenotypes is becoming increasingly important. In the current study using over 4,000 subjects genotyped for 300,000 single-nucleotide polymorphisms (SNPs), we provide further insight into relationships among European population groups and identify sets of SNP ancestry informative markers (AIMs) for application in genetic studies. In general, the graphical description of these principal components analyses (PCA) of diverse European subjects showed a strong correspondence to the geographical relationships of specific countries or regions of origin. Clearer separation of different ethnic and regional populations was observed when northern and southern European groups were considered separately and the PCA results were influenced by the inclusion or exclusion of different self-identified population groups including Ashkenazi Jewish, Sardinian, and Orcadian ethnic groups. SNP AIM sets were identified that could distinguish the regional and ethnic population groups. Moreover, the studies demonstrated that most allele frequency differences between different European groups could be controlled effectively in analyses using these AIM sets. The European substructure AIMs should be widely applicable to ongoing studies to confirm and delineate specific disease susceptibility candidate regions without the necessity of performing additional genome-wide SNP studies in additional subject sets.

Recent progress in genetic studies of Rheumatoid Arthritis (RA) has revealed several new loci as risk factors for disease development (1-7). However, all newly found variations outside the HLA locus provide only limited, although statistically significant, increased risk for RA. The strongest association with ACPA (antibodies to citrullinated protein) -positive RA was repeatedly reported for the HLA-DRB1 gene and it is evident that this genetic locus plays a central role in susceptibility to disease in different Caucasian populations. RA is a complex disease with many different factors involved and it is rational to discern which of the combinations of these factors results in the most aggressive form of the disease. Our own and other previous reports demonstrated an unexpected high increase in risk associated with exposure to smoking in the presence of shared epitope alleles of the HLA-DRB1 gene, with regard to susceptibility to ACPA-positive and/or rheumatoid factor (RF) positive RA, which we considered as strong evidence for an interaction (8-16). According to the current state of knowledge, the association between the HLA-DRB1 variations and susceptibility to ACPA-positive RA is related to more than one allele (*0101, *0401, *0404, *0405, *0408, *1001, *1402). These alleles share a common amino acid sequence (Q/R70K/RRAA74) in the third hypervariable region of the DRB1 molecule and have therefore been denoted the ‘shared epitope’ (SE) (17-20). The SE residues constitute a part of the antigen-binding site forming the fourth anchoring pocket 4 (P4) in the HLA groove. The epitope motif hypothetically serves as a binding site for arthritogenic peptides allowing presentation to CD4+ T cells and generation of T cell autoimmune responses and may possibly induce certain B cells to differentiate into plasma cells, duly leading to the production of ACPA (15). ACPA occur in approximately 60% of RA patients, 2% of healthy populations and is rather rare in patients with other inflammatory diseases (15, 21). The occurrence of ACPA is observed several years before onset of disease (22) and is closely linked to the presence of SE alleles. More specifically, the association between SE and RA, which is the strongest genetic risk factor for disease, is exclusively observed within the ACPA-positive patient subset (8, 9, 15). Several environmental factors have been described with ambiguous results, predisposing or protecting against development of RA (16, 23-27). However, the main environmental risk factor for RA detected to date is smoking (8, 13). A strong gene-environment interaction between tobacco exposure and SE for the ACPA-positive subset has been repeatedly demonstrated in several studies within Europe (8, 10-13), whereas neither smoking nor SE confers an increased risk of ACPA-negative RA. However, when replication of the demonstrated gene-environment interaction was assessed in three North American cohorts by Lee et al (28), evidence of a gene-environment interaction between smoking and SE alleles for ACPA formation could only be observed in one of these. This discrepancy could possibly be explained by different recruitment procedures of controls and patients, diverse methodologies for evaluation of smoking and due to the existence of different sorts of environmental exposure. In a recent study, van der Helm-van Mil et al (8) performed gene-environment analyses stratifying for the *01, *04 and *10 groups in an investigation of 421 patients using ACPA-negative patients as controls. Interestingly, through using a multiplicative model they observed an interaction between tobacco exposure and DRB1*01 and *10 in ACPA-positive RA, but no interaction was evident for the *04 alleles. Herein we employ a large population-based case-control study to scrutinize the gene-environment interaction between smoking and SE alleles in RA. The goal of our investigation was to ascertain whether all HLA-DRB1 SE alleles (HLA-DRB1*01, HLA-DRB1*04, HLA-DRB1*10) present a similar interaction effect or if the interaction is restricted to a particular DRB1 SE group. In addition, we assessed the relevance of studying the different subtypes of *04. More specifically we focused on *0401, *0404, *0405 and *0408, i.e. the ‘true’ SE alleles in the *04 group. Hence in this population-based study we report findings from analyzing *01, *10 and *04 separately as well as subtypes of *04, in the context of smoking and ACPA status in RA.

Objective. Previous studies have demonstrated that the PRL 1149 T (minor) allele decreases prolactin expression and may be associated with autoimmune disease. The aim of this study was to determine the role of the PRL 1149 G/T polymorphism (rs1341239) in rheumatoid arthritis (RA) susceptibility. Methods. We examined the association between PRL 1149 G/T and RA risk in 4 separate study populations, consisting of a total of 3,405 RA cases and 4,111 controls of self-reported white European ancestry. Samples were genotyped using 1 of 3 genotyping platforms, and strict quality control metrics were applied. We tested for association using a 2-tailed CochranMantel-Haenszel additive, fixed-effects model. Results. In the individual populations, odds ratios (ORs) for an association between PRL 1149 T and RA risk ranged from 0.80 to 0.97. In a joint meta-analysis across all 4 populations, the OR for an association between PRL 1149 T and RA risk was 0.90 (95% confidence interval 0.84–0.96, P 0.001). Conclusion. Our findings indicate a possible association between the PRL 1149 T allele and decreased RA risk. The effect size is small but similar to ORs for other genetic polymorphisms associated with complex traits, including RA.

Objective: The phase III GO-FORWARD study examined the efficacy and safety of golimumab in patients with active rheumatoid arthritis (RA) despite methotrexate therapy. Methods: Patients were randomly assigned in a 3 : 3 : 2 : 2 ratio to receive placebo injections plus methotrexate capsules (group 1, n = 133), golimumab 100 mg injections plus placebo capsules (group 2, n = 133), golimumab 50 mg injections plus methotrexate capsules (group 3, n = 89), or golimumab 100 mg injections plus methotrexate capsules (group 4, n = 89). Injections were administered subcutaneously every 4 weeks. The co-primary endpoints were the proportion of patients with 20% or greater improvement in the American College of Rheumatology criteria (ACR20) at week 14 and the change from baseline in the health assessment questionnaire-disability index (HAQ-DI) score at week 24. Results: The proportion of patients who achieved an ACR20 response at week 14 was 33.1% in the placebo plus methotrexate group, 44.4% (p = 0.059) in the golimumab 100 mg plus placebo group, 55.1% (p = 0.001) in the golimumab 50 mg plus methotrexate group and 56.2% (p

With new treatments of inflammatory diseases targeting key inflammatory pathways follows an increased risk for infections. The aim of the present study was to identify an immunological readout where consecutive immunizations induce reproducible immune responses. Such a method could be used as a tool to assess drug-induced immunomodulation in individual patients by comparing responses to the immunizations before and after introduction of a specific treatment. Importantly, the vaccine is merely used as a model antigen and protective immunity is not the primary aim of the method. Eleven volunteers were immunized with influenza vaccine three times, four weeks apart. In order to find the optimal readout for the method, immune responses to the immunizations were measured as circulating antigen-specific B-cells, serum antibody titers and avidity, T-cell proliferation and cytokine secretion. The first exposure to the influenza vaccine induced a stronger B- and T-cell responses than the consecutive immunizations. The second and third immunizations induced comparable but lower B-cell responses as measured by ELISPOT. In summary, we have measured immune responsiveness by using repeated immunizations with influenza virus vaccine as the model antigen. The induction of comparable B-cell responses after the second and third serial immunizations provides a possibility to investigate effects on immune responsiveness by immunomodulatory drugs. The method also allows humoral memory and immune competence per se to be studied on a cellular level in different patient groups.

Background: Whereas many patients respond quickly to treatment with tumour necrosis factor (TNF) inhibitors, some patients may experience significant but delayed responses. Objective: To evaluate the clinical response between 12 and 24 weeks in subjects with rheumatoid arthritis from the Trial of Etanercept and Methotrexate with Radiographic Patient Outcomes. Methods: Clinical response was assessed at 24 weeks in 12-week non-responders, according to American College of Rheumatology (ACR) response criteria. The proportion of subjects who successfully maintained response to 52 weeks was analysed, as were radiographic outcomes. Results: Data from 682 subjects were included in the analysis. Non and partial responders in all three groups (etanercept, methotrexate and etanercept plus methotrexate) at week 12 showed an improvement in responses at week 24. Over 80% of the week 24 ACR20/50/70 responders in the etanercept plus methotrexate arm sustained their response to 52 weeks. In the etanercept arms, a delayed clinical response was not associated with increased radiographic progression at week 52. Conclusion: A significant proportion of non and partial responders to etanercept with or without methotrexate therapy at week 12 achieved a good clinical response or improved their overall clinical response at week 24. Discontinuing TNF inhibitor therapy at 12 weeks may be premature in some rheumatoid arthritis patients.

With the licensing of the first tumour necrosis factor (TNF)alpha inhibitors, independent academia-initiated but industry-sponsored drug registers were set up by the national rheumatology societies in several European countries in order to monitor the long-term safety and effectiveness of this new generation of drugs. Even though different in some respects of study design and monitoring, the registers share a number of common features: they include all licensed biological agents, they observe the patients for a defined period of time or indefinitely irrespective of the drug given and they use comparator cohorts or national registers in order to put the results into perspective. The registers have been collaborating closely since inception. Three of them (the British, Swedish and German registers) have agreed on a standardised reporting system of adverse events which ensures a high and uniform quality of data submitted to the companies, who subsequently report to the drug regulatory authorities, enabling regulatory requirements on safety surveillance to be fulfilled. In the present work, major results on drug safety with regard to infections, malignancies, cardiovascular events, pregnancy outcomes and deaths are summarised. With an increasing number of new drugs and multiple exposures of individual patients the assignment of events to specific treatments will become exceedingly difficult. This and other methodological challenges and the approaches to cope with them are discussed. A growing dialogue between drug regulatory authorities, academic medicine and companies in order to make best use of the potentials of academia-driven drug registers as new tools for pharmacovigilance with currently described rheumatology registers as prototypes is anticipated.

Diffuse large B-cell lymphomas (DLBCL) can be subdivided into germinal centre (GC)-like and non-GC-like subtypes by CD10, BCL6 and MUM1/IRF4 status. We previously reported that patients with severe rheumatoid arthritis (RA) are at increased risk of non-GC DLBCL. This study examined a new GC-marker, human germinal-centre-associated lymphoma (HGAL) protein, in RA-DLBCL. Of 111, 38 (34%) DLBCL were HGAL-positive and showed less disseminated disease and a tendency toward improved overall survival compared to HGAL-negative cases. This supports that a majority of RA-DLBCL are of non-GC origin, indicating a specific role for activated peripheral B cells in the pathogenesis of RA-DLBCL.

Summary The anti-arthritic effects of the synthetic compound 9-chloro-2,3 dimethyl-6-(N,N-dimetylamino-2-oxoethyl)-6H-indolo[2,3-b] quinoxaline (Rob 803) was evaluated by treating Dark Agouti rats with collagen-induced arthritis using three different protocols. Daily subcutaneous treatment with 40 mg/kg/day of Rob 803 from the day of immunization and 14 days forward suppressed arthritis severity significantly and delayed the onset of clinical arthritis. In contrast, similar treatment initiated when individual rats had developed clinical disease (at a score of 2 points) did not suppress disease. Oral treatment with 35 mg/kg/day of Rob 803 from the day of immunization and 21 days forward resulted in a trend towards disease suppression. In vitro analysis of rats treated subcutaneously with Rob 803 revealed an inhibition of T cell proliferation but no effect on the generation of an anti-CII immunoglobulin G response. Further in vitro analysis demonstrated that Rob 803 also inhibited the generation of nitric oxide in macrophages, although at higher concentrations than needed for inhibitory effects on T cell proliferation. Thus we report that early subcutaneous administration of the synthetic substance Rob 803 has anti-rheumatic effects that are probably mediated by affecting the proliferative capacity of lymph node T cells. Rob 803 should be considered as a new candidate substance for anti-rheumatic treatment.

To identify rheumatoid arthritis risk loci in European populations, we conducted a meta-analysis of two published genome-wide association (GWA) studies totaling 3,393 cases and 12,462 controls. We genotyped 31 top-ranked SNPs not previously associated with rheumatoid arthritis in an independent replication of 3,929 autoantibody-positive rheumatoid arthritis cases and 5,807 matched controls from eight separate collections. We identified a common variant at the CD40 gene locus (rs4810485, P = 0.0032 replication, P = 8.2 x 10(-9) overall, OR = 0.87). Along with other associations near TRAF1 (refs. 2,3) and TNFAIP3 (refs. 4,5), this implies a central role for the CD40 signaling pathway in rheumatoid arthritis pathogenesis. We also identified association at the CCL21 gene locus (rs2812378, P = 0.00097 replication, P = 2.8 x 10(-7) overall), a gene involved in lymphocyte trafficking. Finally, we identified evidence of association at four additional gene loci: MMEL1-TNFRSF14 (rs3890745, P = 0.0035 replication, P = 1.1 x 10(-7) overall), CDK6 (rs42041, P = 0.010 replication, P = 4.0 x 10(-6) overall), PRKCQ (rs4750316, P = 0.0078 replication, P = 4.4 x 10(-6) overall), and KIF5A-PIP4K2C (rs1678542, P = 0.0026 replication, P = 8.8 x 10(-8) overall).

Background: Many studies have examined the relationship between long-term radiographic damage and physical function. However, it is not known if short-term radiographic progression is also associated with physical function. Aim: To investigate the longitudinal relationship between physical function and both the level of radiographic damage and the radiographic progression rate in patients with early or advanced active rheumatoid arthritis. Methods: The database for the 2-year Trial of Etanercept and Methotrexate with Radiographic Patient Outcomes (TEMPO) was used for this study. Physical function was measured by the Health Assessment Questionnaire (HAQ) score at baseline, 6 months and 1 and 2 years. Radiographs of the hands and feet, taken at the same time points, were scored by the van der Heijde-modified Total Sharp Score (TSS). The HAQ score was modelled using generalised mixed linear modelling by TSS or progression in TSS (interval 0–1 year and 1–2 years) adjusted for age, sex, treatment and disease activity. Results: After adjustment for age, sex and disease activity, both TSS and the change in TSS (progression rate) were significant determinants of the HAQ score. When radiographic progression was divided into four categories (negative, zero, minor and greater progression), results showed that HAQ scores tended to be higher with a higher rate of progression. Patients with negative progression scores had lower HAQ scores than patients with positive progression scores. Conclusions: Patients with greater radiographic damage, and those with recent radiographic progression, have a higher degree of disability.

During the past 30 years, elucidation of the pathogenesis of rheumatoid arthritis, Crohn's disease, psoriasis, psoriatic arthritis and ankylosing spondylitis at the cellular and molecular levels has revealed that these diseases share common mechanisms and are more closely related than was previously recognized. Research on the complex biology of tumor necrosis factor (TNF) has uncovered many mechanisms and pathways by which TNF may be involved in the pathogenesis of these diseases. There are 3 TNF antagonists currently available: adalimumab, a fully human monoclonal antibody; etanercept, a soluble receptor construct; and infliximab, a chimeric monoclonal antibody. Two other TNF antagonists, certolizumab and golimumab, are in clinical development. The remarkable efficacy of TNF antagonists in these diseases places TNF in the center of our understanding of the pathogenesis of many immune-mediated inflammatory diseases. The purpose of this review is to discuss the biology of TNF and related family members in the context of the potential mechanisms of action of TNF antagonists in a variety of immune-mediated inflammatory diseases. Possible mechanistic differences between TNF antagonists are addressed with regard to their efficacy and safety profiles.

Objective. The Trial of Etanercept and Methotrexate with Radiographic Patient Outcomes (TEMPO) is a 3-year, double-blind, multicenter study evaluating the efficacy and safety of etanercept, methotrexate, and the combination of etanercept plus methotrexate in patients with active rheumatoid arthritis (RA). The results after 1 and 2 years of the study have been previously reported. Here we provide the 3-year clinical and radiographic outcomes and safety of etanercept, methotrexate, and the combination in patients with RA. Methods. In this randomized, double-blind, multicenter TEMPO study, 682 patients received etanercept 25 mg twice weekly, methotrexate ≤20 mg weekly, or the combination. Key efficacy assessments included the Disease Activity Score (DAS) and the DAS in 28 joints. Results. Combination therapy resulted in significantly greater improvement in the DAS and in more patients with disease in remission than either monotherapy. This finding was confirmed by longitudinal analysis; patients receiving combination therapy were more than twice as likely to have disease in remission than those receiving either monotherapy. Independent predictors of remission included male sex, lower disease activity, lower level of joint destruction, and/or better physical function. Combination and etanercept therapy both resulted in significantly less radiographic progression than did methotrexate (P < 0.05). Etanercept and combination treatment were well tolerated, with no new safety findings. Conclusion. Etanercept plus methotrexate showed sustained efficacy through 3 years and remained more effective than either monotherapy, even after adjustment for patient withdrawal. Combination therapy for 3 years led to disease remission and inhibition of radiographic progression, 2 key goals for treatment of patients with RA. © 2007, American College of Rheumatology.

Rheumatoid arthritis (RA) is a severe and common inflammatory disease with unclear etiology, but is likely to be precipitated and modulated by complex interactions between genetic and environmental factors. Efficient prevention or cure of RA has not yet been developed. Numerous attempts to understand the disease mechanisms and to suggest preventive measures have not been successful. Lately, defining major subtypes of RA by the presence of autoantibodies has been very productive when studying genetic and environmental risk factors for RA. The most replicated risk factors for RA are variations in the HLA-DRB1 gene and smoking and there is also evidence that there is a dose response relationship (i.e., greater number of cigarettes and longer duration of smoking are associated with increased risk of RA). However, these risk factors as well as their interaction have mainly been associated with anticitrullinated peptide antibodies and/or rheumatoid factor positive RA. More research is needed to identify the env...

Gene-gene and gene-environment interactions are key features in the development of rheumatoid arthritis (RA) and other complex diseases. The aim of this study was to use and compare three different definitions of interaction between the two major genetic risk factors of RA--the HLA-DRB1 shared epitope (SE) alleles and the PTPN22 R620W allele--in three large case-control studies: the Swedish Epidemiological Investigation of Rheumatoid Arthritis (EIRA) study, the North American RA Consortium (NARAC) study, and the Dutch Leiden Early Arthritis Clinic study (in total, 1,977 cases and 2,405 controls). The EIRA study was also used to analyze interactions between smoking and the two genes. "Interaction" was defined either as a departure from additivity, as interaction in a multiplicative model, or in terms of linkage disequilibrium--for example, deviation from independence of penetrance of two unlinked loci. Consistent interaction, defined as departure from additivity, between HLA-DRB1 SE alleles and the A allele of PTPN22 R620W was seen in all three studies regarding anti-CCP-positive RA. Testing for multiplicative interactions demonstrated an interaction between the two genes only when the three studies were pooled. The linkage disequilibrium approach indicated a gene-gene interaction in EIRA and NARAC, as well as in the pooled analysis. No interaction was seen between smoking and PTPN22 R620W. A new pattern of interactions is described between the two major known genetic risk factors and the major environmental risk factor concerning the risk of developing anti-CCP-positive RA. The data extend the basis for a pathogenetic hypothesis for RA involving genetic and environmental factors. The study also raises and illustrates principal questions concerning ways to define interactions in complex diseases.

Objective: To formulate EULAR recommendations for the management of early arthritis. Methods: In accordance with EULAR’s “standardised operating procedures”, the task force pursued an evidence based approach and an approach based on expert opinion. A steering group comprised of 14 rheumatologists representing 10 European countries. The group defined the focus of the process, the target population, and formulated an operational definition of “management”. Each participant was invited to propose issues of interest regarding the management of early arthritis or early rheumatoid arthritis. Fifteen issues for further research were selected by use of a modified Delphi technique. A systematic literature search was carried out. Evidence was categorised according to usual guidelines. A set of draft recommendations was proposed on the basis of the research questions and the results of the literature search.. The strength of the recommendations was based on the category of evidence and expert opinion. Results: 15 research questions, covering the entire spectrum of “management of early arthritis”, were formulated for further research; and 284 studies were identified and evaluated. Twelve recommendations for the management of early arthritis were selected and presented with short sentences. The selected statements included recognition of arthritis, referral, diagnosis, prognosis, classification, and treatment of early arthritis (information, education, non-pharmacological interventions, pharmacological treatments, and monitoring of the disease process). On the basis of expert opinion, 11 items were identified as being important for future research. Conclusions: 12 key recommendations for the management of early arthritis or early rheumatoid arthritis were developed, based on evidence in the literature and expert consensus.

This review has two purposes: to describe the known effects of cigarette smoking on the development of inflammatory rheumatic diseases, in particular rheumatoid arthritis and systemic lupus erythematosus, and to review recent research aimed at understanding the mechanisms by which smoking may interact with genes and immunity in triggering these diseases.Large case-control studies as well as cohort studies have demonstrated that cigarette smoking is a risk factor for RF positive and anti-citrulline antibody with rheumatoid arthritis and that the risk diminishes only several years after cessation of smoking. Evidence exists that smoking is a risk factor also for systemic lupus erythematosus, and that the risk may be related to the presence of anti-dsDNA antibodies. Mechanistic studies are reviewed that suggest that smoking can trigger specific and potentially disease-inducing immune reactions against citrullinated proteins in rheumatoid arthritis, and dsDNA in systemic lupus erythematosus, and it is suggested that the genetic context determines which immune reactions may be triggered by smoking.Counselling against smoking should be mandatory in rheumatological practice both to patients and to their relatives. Studies on the mechanisms whereby smoking triggers rheumatoid arthritis and systemic lupus erythematosus may provide fundamental new knowledge about the cause and molecular pathogenesis of these diseases.

Herein we investigated how rituximab-induced B cell depletion affected leukocyte subpopulations and antibody titers in SLE patients. We focused our analysis on time points related to absence and return of B cells after depletion. A correlation was found between the baseline frequency and time to repopulation; the fewer B cells initially, the longer to their return. While the few B cells remaining after treatment were of memory, double-negative (IgD-CD27-), and CD5+ phenotype, the returning B cells were mainly naïve, indicating de novo production of B cells. Serum levels of IgG and antibodies against Ro52, Ro60, La44, measles and tetanus remained unchanged, while decreases in IgM, IgE, anti-dsDNA and anti-C1q antibodies were observed. Additionally, a significant increase in activated CD4+ and CD8+ T cells, as well as CD25bright FOXP3+ regulatory T cells was observed. In conclusion, both the humoral and the cellular immune systems were affected by treatment with rituximab.

Objective To identify susceptibility genes in a rat model of rheumatoid arthritis (RA) and to determine whether the corresponding human genes are associated with RA. Methods Genes influencing oil-induced arthritis (OIA) were position mapped by comparing the susceptibility of inbred DA rats with that of DA rats carrying alleles derived from the arthritis-resistant PVG strain in chromosomal fragments overlapping the quantitative trait locus Oia2. Sequencing of gene complementary DNA (cDNA) and analysis of gene messenger RNA (mRNA) expression were performed to attempt to clone a causal gene. Associations with human RA were evaluated by genotyping single-nucleotide polymorphisms (SNPs) in the corresponding human genes and by analyzing frequencies of alleles and haplotypes in RA patients and age-, sex-, and area-matched healthy control subjects. Results Congenic DA rats were resistant to OIA when they carried PVG alleles for the antigen-presenting lectin-like receptor gene complex (APLEC), which encodes immunoregulatory C-type lectin–like receptors. Multiple differences in cDNA sequence and mRNA expression precluded cloning of a single causal gene. Five corresponding human APLEC genes were identified and targeted. The SNP rs1133104 in the dendritic cell immunoreceptor gene (DCIR), and a haplotype including that marker and 4 other SNPs in DCIR and its vicinity showed an indication of allelic association with susceptibility to RA in patients who were negative for antibodies to cyclic citrullinated peptide (anti-CCP), with respective odds ratios of 1.27 (95% confidence interval [95% CI] 1.06–1.52; uncorrected P = 0.0073) and 1.37 (95% CI 1.12–1.67; uncorrected P = 0.0019). Results of permutation testing supported this association of the haplotype with RA. Conclusion Rat APLEC is associated with susceptibility to polyarthritis, and human APLEC and DCIR may be associated with susceptibility to anti-CCP–negative RA.

Background: A long-standing epidemiological puzzle is the reduced rate of rheumatoid arthritis (RA) in those with schizophrenia (SZ) and vice versa. Traditional epidemiological approaches to determine if this negative association is underpinned by genetic factors would test for reduced rates of one disorder in relatives of the other, but sufficiently powered data sets are difficult to achieve. The genomics era presents an alternative paradigm for investigating the genetic relationship between two uncommon disorders. Methods: We use genome-wide common single nucleotide polymorphism (SNP) data from independently collected SZ and RA case-control cohorts to estimate the SNP correlation between the disorders. We test a genotype X environment (GxE) hypothesis for SZ with environment defined as winter- vs summer-born. Results: We estimate a small but significant negative SNP-genetic correlation between SZ and RA (−0.046, s.e. 0.026, P = 0.036). The negative correlation was stronger for the SNP set attributed to coding or regulatory regions (−0.174, s.e. 0.071, P = 0.0075). Our analyses led us to hypothesize a gene-environment interaction for SZ in the form of immune challenge. We used month of birth as a proxy for environmental immune challenge and estimated the genetic correlation between winter-born and non-winter born SZ to be significantly less than 1 for coding/regulatory region SNPs (0.56, s.e. 0.14, P = 0.00090). Conclusions: Our results are consistent with epidemiological observations of a negative relationship between SZ and RA reflecting, at least in part, genetic factors. Results of the month of birth analysis are consistent with pleiotropic effects of genetic variants dependent on environmental context. Refereed/Peer-reviewed

ObjectivesLung exposures including cigarette smoking and silica exposure are associated with the risk of rheumatoid arthritis (RA). We investigated the association between textile dust exposure and the risk of RA in the Malaysian population, with a focus on women who rarely smoke.MethodsData from the Malaysian Epidemiological Investigation of Rheumatoid Arthritis population-based case–control study involving 910 female early RA cases and 910 female age-matched controls were analysed. Self-reported information on ever/never occupationally exposed to textile dust was used to estimate the risk of developing anti-citrullinated protein antibody (ACPA)-positive and ACPA-negative RA. Interaction between textile dust and the human leucocyte antigen DR β-1 (HLA-DRB1) shared epitope (SE) was evaluated by calculating the attributable proportion due to interaction (AP), with 95% CI.ResultsOccupational exposure to textile dust was significantly associated with an increased risk of developing RA in the Malaysian female population (OR 2.8, 95% CI 1.6 to 5.2). The association between occupational exposure to textile dust and risk of RA was uniformly observed for the ACPA-positive RA (OR 2.5, 95% CI 1.3 to 4.8) and ACPA-negative RA (OR 3.5, 95% CI 1.7 to 7.0) subsets, respectively. We observed a significant interaction between exposure to occupational textile dust and HLA-DRB1 SE alleles regarding the risk of ACPA-positive RA (OR for double exposed: 39.1, 95% CI 5.1 to 297.5; AP: 0.8, 95% CI 0.5 to 1.2).ConclusionsThis is the first study demonstrating that textile dust exposure is associated with an increased risk for RA. In addition, a gene–environment interaction between HLA-DRB1 SE and textile dust exposure provides a high risk for ACPA-positive RA.

Immunglobulin G (IgG) sialylation represents a key checkpoint that determines the engagement of pro- or anti-inflammatory Fcγ receptors (FcγR) and the direction of the immune response. Whether IgG sialylation influences osteoclast differentiation and subsequently bone architecture has not been determined yet, but may represent an important link between immune activation and bone loss. Here we demonstrate that desialylated, but not sialylated, immune complexes enhance osteoclastogenesis in vitro and in vivo. Furthermore, we find that the Fc sialylation state of random IgG and specific IgG autoantibodies determines bone architecture in patients with rheumatoid arthritis. In accordance with these findings, mice treated with the sialic acid precursor N-acetylmannosamine (ManNAc), which results in increased IgG sialylation, are less susceptible to inflammatory bone loss. Taken together, our findings provide a novel mechanism by which immune responses influence the human skeleton and an innovative treatment approach to inhibit immune-mediated bone loss.