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Van Schouwenburg P.A.,Sanquin Research | Rispens T.,Sanquin Research | Wolbink G.J.,Jan van Breemen Research Institute
Nature Reviews Rheumatology | Year: 2013

Currently, five anti-TNF biologic agents are approved for the treatment of rheumatoid arthritis (RA): adalimumab, infliximab, etanercept, golimumab and certolizumab pegol. Formation of anti-drug antibodies (ADA) has been associated with all five agents. In the case of adalimumab and infliximab, immunogenicity is strongly linked to subtherapeutic serum drug levels and a lack of clinical response, but for the other three agents, data on immunogenicity are scarce, suggesting that further research would be valuable. Low ADA levels might not influence the efficacy of anti-TNF therapy, whereas high ADA levels impair treatment efficacy by considerably reducing unbound drug levels. Immunogenicity is not only an issue in patients treated with anti-TNF biologic agents; the immunogenicity of other therapeutic proteins, such as factor VIII and interferons, is well known and has been investigated for many years. The results of such studies suggest that investigations to determine the optimal treatment regimen (drug dosing, treatment schedule and co-medication) required to minimize the likelihood of ADA formation might be an effective and practical way to deal with the immunogenicity of anti-TNF biologic agents for RA. © 2013 Macmillan Publishers Limited. All rights reserved. Source

Karlson E.W.,Brigham and Womens Hospital | Van Schaardenburg D.,Jan van Breemen Research Institute | Van der Helm-van Mil A.H.,Leiden University
Rheumatology (United Kingdom) | Year: 2016

The development of RA is conceived as a multiple hit process and the more hits that are acquired, the greater the risk of developing clinically apparent RA. Several at-risk phases have been described, including the presence of genetic and environmental factors, RA-related autoantibodies and biomarkers and symptoms. Intervention in these preclinical phases may be more effective compared with intervention in the clinical phase. One prerequisite for preventive strategies is the ability to estimate an individual's risk adequately. This review evaluates the ability to predict the risk of RA in the various preclinical stages. Present data suggest that a combination of genetic and environmental factors is helpful to identify persons at high risk of RA among first-degree relatives. Furthermore, a combination of symptoms, antibody characteristics and environmental factors has been shown to be relevant for risk prediction in seropositive arthralgia patients. Large prospective studies are needed to validate and improve risk prediction in preclinical disease stages. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. Source

Rombouts Y.,Leiden University | Ewing E.,Leiden University | Van De Stadt L.A.,Jan van Breemen Research Institute | Selman M.H.J.,Leiden University | And 8 more authors.
Annals of the Rheumatic Diseases | Year: 2015

Methods: Serum samples of patients with ACPA-positive arthralgia (n=183) were collected at baseline and at various time points of follow-up. 105 patients developed arthritis after a median of 12 months (IQR 6-24) and were classified as having either rheumatoid arthritis (RA, n=48) or undifferentiated arthritis (UA, n=57) based on the 1987 American College of Rheumatology (ACR) criteria. ACPA and total serum IgG were isolated by affinity purification and cleaved by trypsin. ACPA-IgG1 Fc-glycopeptides were subsequently analysed by nano-liquid chromatography mass spectrometry and compared to those of total IgG1.Objective: To determine whether anticitrullinated protein antibodies (ACPA) exhibit specific changes in Fc glycosylation prior to the onset of arthritis.Results: At baseline, ACPA-IgG1 and total IgG1 from arthralgia patients displayed similar Fc glycosylation patterns. By contrast, at the onset of arthritis, ACPA exhibited a decrease in galactose residues in RA patients, but not in UA patients. This decrease occurred around 3 months prior to diagnosis and was paralleled by an increase in systemic inflammation (erythrocyte sedimentation rate). Galactosylation of total IgG1 was also decreased in RA, but this did not precede the onset of arthritis. Interestingly, we additionally noted a higher degree of ACPA-IgG1 Fc core fucosylation at baseline as compared with total IgG1, which further increased prior to diagnosis.Conclusions: ACPA display significant changes in Fc galactosylation and fucosylation prior to the onset of RA. These changes towards a more pro-inflammatory phenotype could be involved in driving the disease process. Source

Shi J.,Leiden University | Van De Stadt L.A.,Jan van Breemen Research Institute | Van De Stadt L.A.,University of Amsterdam | Levarht E.W.N.,Leiden University | And 6 more authors.
Annals of the Rheumatic Diseases | Year: 2014

Objective: The presence of anti-citrullinated protein antibodies (ACPA) and IgM-rheumatoid factor (IgM-RF) years before the clinical diagnosis of rheumatoid arthritis (RA) suggests they are possibly involved in the pathogenic process underlying RA. In this study, we analysed whether anti-carbamylated protein (anti-CarP) antibodies, a novel autoantibody system against carbamylated proteins, can also be detected in healthy individuals before they developed RA. Methods: Multiple sera from asymptomatic blood donors prior to the onset of their RA symptoms and sera from age-matched and sex-matched controls were tested for the presence of antibodies directed against carbamylated-fetal calf serum (Ca-FCS), carbamylatedfibrinogen (Ca-Fib), cyclic citrullinated-peptide 2 and IgM-RF. Results: Anti-Ca-FCS and anti-Ca-Fib antibodies were each present in 27% and 38% of the last serum samples of blood donors prior to the diagnosis of RA. Both anti-Ca-FCS and anti-Ca-Fib antibodies could be detected many years before the onset of RA. Anti-CarP antibodies as well as ACPA are, on average, detected earlier than IgM-RF. Conclusions: In addition to ACPA and IgM-RF, also the newly identified anti-CarP antibodies appear many years before the diagnosis of RA. Source

Suwannalai P.,Leiden University | Suwannalai P.,Mahidol University | Britsemmer K.,Jan van Breemen Research Institute | Knevel R.,Leiden University | And 7 more authors.
Annals of the Rheumatic Diseases | Year: 2014

Objectives Anticitrullinated protein antibodies (ACPA) are specific for rheumatoid arthritis (RA) and have been implicated in disease pathogenesis. Previously we have shown that ACPA display a considerably lower avidity as compared with antibodies against recall antigens. Nonetheless, ACPA-avidity did vary between patients. As antibody mediated effects are influenced by antibodyavidity, we now investigated ACPA-avidity in relation to biological activity and clinical outcome. Methods We determined the avidity of ACPA and related this with severity of joint damage in two Dutch early-RA cohorts containing 199 and 132 patients respectively. Differences in effector functions of low- and high-avidity ACPA were studied. Results Extensive variation in ACPA-avidity between patients was observed. This allowed the analysis of the relationship between avidity and severity. The presence of low-avidity ACPA is associated with a higher rate of joint destruction. This finding was replicated in an independent cohort. Analysis of the properties of lowversus high-avidity ACPA revealed that low-avidity ACPA are less hampered in their ability to bind 'new' citrullinated antigens. Although no differences could be observed regarding cellular activation via Fc-γ receptors, low-avidity ACPA were more potent in activating the complement system. Conclusions Patients with low-avidity ACPA display a higher rate of joint destruction. Low-avidity ACPA display a higher potency to interact with more citrullinated antigens in time and show that low-avidity ACPA are more potent in complement activation. These data indicate that (low) avidity impacts on the biological activity of ACPA and associates with a worse radiological outcome. Source

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