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Contains fulltext : 307088.pdf (Publisher’s version ) (Closed access), Radboud University, 04 juli 2024, Promotor : Jong, E.M.G.J. de Co-promotores : Wenink, M.H., Reek, J.M.P.A. van den, Vriezekolk, J.E., 310 p.

Item does not contain fulltext, Patients with psoriasis are at risk of developing psoriatic arthritis, which can lead to joint damage. While screening questionnaires have been developed, their performance varies. The objective of this study was to develop a referral tool for dermatologists to identify psoriasis patients with concomitant psoriatic arthritis for rheumatological referral. This study used data from the DAPPER study, in which psoriasis patients were screened by a rheumatologist for the presence of concomitant psoriatic arthritis. Multivariable regression analysis was used to identify predictive variables for the presence of concomitant psoriatic arthritis: treatment history with conventional systemic drugs (odds ratio (OR) 2.97, 95% confidence interval (95% CI) 1.01-8.74, p = 0.04), treatment history with biologicals/small molecule inhibitors (OR 2.90, 95% CI 1.52-5.53, p = 0.01), patient-reported history of joint pain not caused by trauma (OR 4.23, 95% CI 1.21-14.79, p = 0.01), patient-reported history of swollen joints (OR 4.25, 95% CI 2.17-8.32, p < 0.001), and patient-reported history of sausage-like swollen digits (OR 2.38, 95% CI 1.25-4.55, p = 0.01). Based on these variables, a referral tool was created with an area under the curve of 0.82. This referral tool could be used to aid dermatologists to identify psoriasis patients with concomitant psoriatic arthritis, who may benefit from rheumatological referral.

Contains fulltext : 282872.pdf (Publisher’s version ) (Open Access), Patients with psoriasis are at risk of developing psoriatic arthritis, which can lead to irreversible joint damage. However, a proportion of patients with psoriasis and concomitant psoriatic arthritis remain undiscovered in practice. The aims of this study were: to prospectively determine prevalence, characteristics, and disease burden of psoriatic arthritis in a psoriasis population; and to determine the prevalence and characteristics of patients with active psoriatic arthritis, who were not under rheumatological care. Patients with psoriasis were screened by a rheumatologist at the dermatology outpatient clinic for psoriatic arthritis. Patients with suspected active psoriatic arthritis who were not seeing a rheumatologist were referred to a rheumatologist for confirmation. The total prevalence of psoriatic arthritis in this observational, prospective cohort (n = 303) was 24%. Patients with psoriasis with concomitant psoriatic arthritis had longer duration of skin disease and more often a treatment history with systemic therapies. In this academic, specialized, setting, 2.3% of patients (n = 7), were not receiving rheumatological care despite having active psoriatic arthritis. These patients were characterized by a combination of low (perceived) disease burden and low yield of screening questionnaires, making it difficult for dermatologists to discover psoriatic arthritis in these patients. Thus, screening for more subtle active arthritis in patients with psoriasis in a dermatology setting could be improved.

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Radboud University, 23 september 2022, Promotores : Hoogen, F.H.J. van den, Jong, E.M.G.J. de Co-promotores : Wenink, M.H., Koenen, J.P.M., Contains fulltext : 253110.pdf (Publisher’s version ) (Open Access)

Contains fulltext : 242597.pdf (Publisher’s version ) (Open Access), BACKGROUND: One in three patients with psoriasis will develop psoriatic arthritis (PsA). If left untreated, this can lead to pain, impaired function, and irreversible joint damage. Timely recognition and referral to a rheumatologist are therefore key. However, current methods used to screen patients with psoriasis for those who might benefit from referral to a rheumatologist are not performing well enough. OBJECTIVE: The Discovery of Arthritis in Psoriasis Patients for Early Rheumatological Referral (DAPPER) study is designed to determine the prevalence of PsA in a psoriasis population and to find parameters that can be used to develop a new or enhance an existing instrument for a rheumatological referral. METHODS: DAPPER is a longitudinal observational study with a 1-year follow-up. Patients with psoriasis (N=300) who are treated at an outpatient dermatological clinic will be screened extensively for signs and symptoms of PsA by a trained rheumatologist. If there is clinical suspicion of PsA and the patient is not yet treated by a rheumatologist, referral to the Department of Rheumatology will follow for confirmation of the diagnosis and further care. After 1 year, data on changes in quality of life and PsA and psoriasis disease activity will be collected from the referred patients. The screening visit will be used to gather demographical and medical data, which can later be used to develop the aforementioned screening instrument. RESULTS: Inclusion started in June 2019 and finished in June 2021. Follow-up with newly discovered patients with PsA is ongoing. CONCLUSIONS: The DAPPER study is specifically designed to improve the detection of existing PsA in a dermatologic outpatient setting. Although internal validity will be tested, external validity will have to be checked using a second validation cohort. To predict the development of PsA in the future, longitudinal/prospective data collection is required and will be performed in a follow-up study (DAPPER-i). TRIAL

Contains fulltext : 240688.pdf (Publisher’s version ) (Open Access)

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Contains fulltext : 235267.pdf (Publisher’s version ) (Open Access), Twenty to thirty percent of psoriasis (Pso) patients will develop psoriatic arthritis (PsA). Detection of Pso patients that are (at risk for) developing PsA is essential to prevent structural damage. We conducted a systematic search of five bibliographic databases, up to May 2020. We searched for studies assessing markers (clinical, laboratory, genetic) associated with the development or presence of PsA in Pso patients. Study selection and quality assessment of the included studies was performed, followed by a qualitative best evidence synthesis to determine the level of evidence for a marker and its association with concomitant/developing PsA in Pso. Overall, 259 possible markers were identified in 119 studies that met the inclusion criteria. Laboratory markers related to inflammation and bone metabolism reached a strong level of evidence for the association (not prediction) of PsA in Pso. Only CXCL10 showed strong evidence for a positive predictive value for PsA in Pso. The importance of timely detecting PsA in a Pso population, and finding more (bio)markers contributing to early detection, remains high.

Contains fulltext : 217334.pdf (publisher's version ) (Open Access)

Contains fulltext : 217628.pdf (publisher's version ) (Open Access)

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Background: Although patients have different treatment preferences, these individual preferences could often be grouped in subgroups with shared preferences. Knowledge of these subgroups as well as factors associated with subgroup membership supports health care professionals in the understanding of what matters to patients in clinical decision-making. Objectives: To identify subgroups of patients with rheumatoid arthritis (RA) based on their shared preferences toward disease-modifying antirheumatic drugs (DMARDs), and to identify factors associated with subgroup membership. Methods: A discrete choice experiment to determine DMARD preferences of adult patients with RA was designed based on a literature review, expert recommendations, and focus groups. In this multicenter study, patients were asked to state their preferred choice between two different hypothetical treatment options, described by seven DMARD characteristics with three levels within each characteristic. Latent class analyses and multinomial logistic regressions were used to identify subgroups and the characteristics (patient characteristics, disease-related variables, and beliefs about medicines) associated with subgroup membership. Results: Among 325 participating patients with RA, three subgroups were identified: an administration-driven subgroup (45.6%), a benefit-driven subgroup (29.7%), and a balanced subgroup (24.7%). Patients who were currently using biologic DMARDs were significantly more likely to belong to the balanced subgroup than the administration-driven subgroup (relative risk ratio (RRR): 0.50, 95% CI: 0.28–0.89). Highly educated patients were significantly more likely to belong to the benefit-driven subgroup than the balanced subgroup (RRR: 11.4, 95% CI: 0.97–133.6). Patients’ medication-related concerns did not contribute significantly to subgroup membership, whereas a near-significant association was found between patients’ beliefs about medication necessity and their membership of t

Contains fulltext : 141331.pdf (publisher's version ) (Open Access), BACKGROUND: In rheumatoid arthritis (RA) macrophages play a major role in amplifying synovial inflammation. Important activating signals are those induced by Toll-like receptor (TLR) ligands and by activated T cells. The balance between activating and inhibitory Fc gamma receptors (FcgammaRs) on macrophages might be crucial in modulating these inflammatory responses. The purpose of this study was to determine FcgammaR expression on pro- and anti-inflammatory macrophages (gmMphi and mMphi, respectively) and identify functional consequences on immune complex uptake and macrophage activation. METHODS: Human monocytes were isolated and differentiated into gmMphi and mMphi. A full FcgammaR characterization of both macrophage subtypes was performed and uptake of fluorescent immune complexes (ICs) was determined. FcgammaRIIb isoforms were determined by qPCR. Macrophages were stimulated via different TLRs or cytokine activated T cells in the presence or absence of ICs and cytokine production was determined. Blocking studies were performed to look into the pathways involved. RESULTS: mMphi expressed high levels of the activating FcgammaRIIa and FcgammaRIII and low levels of the inhibitory FcgammaRIIb, while the FcgammaR balance on gmMphi was shifted towards the inhibitory FcgammaRIIb. This was accompanied by a clear increase in FcgammaRIIb1 mRNA expression in gmMphi. This resulted in higher IC uptake by mMphi compared to gmMphi. Furthermore, FcgammaR-mediated stimulation of gmMphi inhibited TLR2, 3, 4 and 7/8 mediated cytokine production via FcgammaRIIb and PI3K signaling. In addition, gmMphi but not mMphi produced TNFalpha upon co-culture with cytokine activated T cells, which was reduced by IC binding to FcgammaRIIb. The latter was dependent on PI3K signaling and COX2. CONCLUSIONS: FcgammaR expression patterns on gmMphi and mMphi are significantly different, which translates in clear functional differences further substantiating FcgammaRIIb as an interesting target for inf

Contains fulltext : 109563.pdf (publisher's version ) (Open Access), BACKGROUND: Costimulation of murine macrophages with immune complexes (ICs) and TLR ligands leads to alternative activation. Studies on human myeloid cells, however, indicate that ICs induce an increased pro-inflammatory cytokine production. This study aimed to clarify the effect of ICs on the pro- versus anti-inflammatory profile of human polarized macrophages. MATERIALS AND METHODS: Monocytes isolated from peripheral blood of healthy donors were polarized for four days with IFN-gamma, IL-4, IL-10, GM-CSF, M-CSF, or LPS, in the presence or absence of heat aggregated gamma-globulins (HAGGs). Phenotypic polarization markers were measured by flow cytometry. Polarized macrophages were stimulated with HAGGs or immobilized IgG alone or in combination with TLR ligands. TNF, IL-6, IL-10, IL-12, and IL-23 were measured by Luminex and/or RT-qPCR. RESULTS: HAGGs did not modulate the phenotypic polarization and the cytokine production of macrophages. However, HAGGs significantly altered the TLR-induced cytokine production of all polarized macrophage subsets, with the exception of MPhi(IL-4). In particular, HAGGs consistently enhanced the TLR-induced IL-10 production in both classically and alternatively polarized macrophages (M1 and M2). The effect of HAGGs on TNF and IL-6 production was less pronounced and depended on the polarization status, while IL-23p19 and IL-12p35 expression was not affected. In contrast with HAGGs, immobilized IgG induced a strong upregulation of not only IL-10, but also TNF and IL-6. CONCLUSION: HAGGs alone do not alter the phenotype and cytokine production of in vitro polarized human macrophages. In combination with TLR-ligands, however, HAGGs but not immobilized IgG shift the cytokine production of distinct macrophage subsets toward IL-10.

Radboud Universiteit Nijmegen, 15 juni 2012, Promotor : Riel, P.L.C.M. van Co-promotor : Radstake, T.R.D.J., Contains fulltext : 93619.pdf (publisher's version ) (Open Access)

Item does not contain fulltext, OBJECTIVE: The pathogenesis of psoriatic arthritis (PsA) remains poorly understood. The underlying chronic inflammatory immune response is thought to be triggered by unknown environmental factors potentially arising from a defective immune function. We undertook this study to determine whether an impaired acute inflammatory response by dendritic cells (DCs) might compromise the clearance of bacteria and predispose to chronic inflammation. METHODS: We determined cytokine production by DCs from healthy controls and from patients with rheumatoid arthritis, PsA, and psoriasis in response to Mycobacterium tuberculosis, Mycobacterium avium paratuberculosis, and a range of other bacteria and Toll-like receptor (TLR) ligands. Phenotypic differences involved in cellular responses against (myco)bacteria were determined by quantitative polymerase chain reaction and flow cytometry. RESULTS: The secretion of proinflammatory cytokines by PsA DCs was impaired upon in vitro challenge with mycobacteria and TLR-2 ligands. This impairment was associated with elevated serum levels of C-reactive protein. The expression of TLR-2 and other receptors known to mediate mycobacterial recognition was unaltered. In contrast, the intracellular TLR inhibitors suppressor of cytokine signaling 3 and A20 were more highly expressed in DCs from PsA patients. PsA DCs further demonstrated up-regulated levels of ATG16L1, NADPH oxidase 2, and LL37, which are molecules implicated in the immune response against intracellular bacteria. CONCLUSION: Our findings indicate that DCs from PsA patients have a disordered immune response toward some species of (myco)bacteria. This might predispose to impaired immune responses to, and in turn impaired clearance of, these bacteria, setting the stage for the chronic inflammation of joints, entheses, skin, and the gut.

Contains fulltext : 88238.pdf (publisher's version ) (Open Access)

Contains fulltext : 81045.pdf (publisher's version ) (Closed access), BACKGROUND: Rheumatoid arthritis (RA) has been associated with an increased risk of infections, but the underlying pathways have not yet been identified. Toll-like receptors (TLR) probably play a role in synovial inflammation and may also contribute to the understanding of the role of infections in RA. OBJECTIVES: To investigate if the synovial expression of TLR3 and TLR7 in RA correlates with that of inflammatory cytokines, and to assess whether this has functional consequences for local cytokine production and to study potential links between the TLR3/7 axis and TLR4 in RA synovium. METHODS: Immunohistochemistry was used to study the expression of TLR3, TLR7, interferon alpha (IFNalpha), tumour necrosis factor alpha (TNFalpha) and interleukins IL1beta, IL12, IL17 and IL18 in RA synovium obtained by arthroscopy from 34 patients with RA. Monocytes, monocyte-derived dendritic cells (MoDCs) and RA synovial fibroblasts were stimulated via TLR3 (poly-IC) and TLR7 (loxorubin), after which IL1beta, IL6 and TNFalpha were measured by Luminex bead array technology. Following preincubation with IFNalpha, IL1beta and IL18, TLR3 and TLR7 mRNA expression was assessed using real-time PCR. Cytokine production after preincubation with IFNalpha and subsequent TLR stimulation was measured. RESULTS: Synovial TLR3/7 expression was co-expressed with IFNalpha, IL1beta and IL18, but not with TNFalpha, IL12 and IL17. Stimulation of TLR3/TLR7 on monocytes, MoDCs or synovial fibroblasts led to secretion of type I IFN but no biologically active IL1beta or IL18 could be detected. Type I IFNalpha increased TLR3/7 mRNA expression whereas IL1beta and IL18 did not. In spite of the fact that the mRNA level of TLR4 remained unchanged, IFNalpha enhanced the response to TLR4 agonists, a phenomenon that was clearly more marked in patients with RA. CONCLUSION: Type I interferons are highly co-expressed with TLR3/TLR7 in RA synovium. They enhance TLR3/TLR7-mediated cytokine production and also TLR4-media

Contains fulltext : 80239.pdf (publisher's version ) (Open Access), BACKGROUND: Regulatory T cells (Tregs) are essential in the control of tolerance. Evidence implicates Tregs in human autoimmune conditions. Here we investigated their role in systemic sclerosis (SSc). METHODS/PRINCIPAL FINDINGS: Patients were subdivided as having limited cutaneous SSc (lcSSc, n = 20) or diffuse cutaneous SSc (dcSSc, n = 48). Further subdivision was made between early dcSSc (n = 24) and late dcSSc (n = 24) based upon the duration of disease. 26 controls were studied for comparison. CD3+ cells were isolated using FACS and subsequently studied for the expression of CD4, CD8, CD25, FoxP3, CD127, CD62L, GITR, CD69 using flow cytometry. T cell suppression assays were performed using sorted CD4CD25(high)CD127(-) and CD4CD25(low)CD127(high) and CD3(+) cells. Suppressive function was correlated with CD69 surface expression and TGFbeta secretion/expression. The frequency of CD4(+)CD25(+) and CD25(high)FoxP3(high)CD127(neg) T cells was highly increased in all SSc subgroups. Although the expression of CD25 and GITR was comparable between groups, expression of CD62L and CD69 was dramatically lower in SSc patients, which correlated with a diminished suppressive function. Co-incubation of Tregs from healthy donors with plasma from SSc patients fully abrogated suppressive activity. Activation of Tregs from healthy donors or SSc patients with PHA significantly up regulated CD69 expression that could be inhibited by SSc plasma. CONCLUSIONS/SIGNIFICANCE: These results indicate that soluble factors in SSc plasma inhibit Treg function specifically that is associated with altered Treg CD69 and TGFbeta expression. These data suggest that a defective Treg function may underlie the immune dysfunction in systemic sclerosis.

Contains fulltext : 81401.pdf (publisher's version ) (Closed access), TLR2 plays an important role in the removal of Gram-positive bacteria; contrastingly, it also appears to have important protective effects against unrestrained inflammation and subsequent organ injury during infection and autoimmunity. We hypothesized that TLR2 tunes the phenotype of dendritic cells (DCs) activated through other TLRs, thereby fulfilling a crucial role in the modulation of the immune response. TLR2 potently inhibited TLR4- and TLR7/8-induced cytokine production by human DCs. The inhibitory effect of TLR2 on the release of TNF-alpha but not of IL-12p70 was mediated by PI3K. TLR2 inhibits the production of IL-12p70 by dampening the type 1 IFN amplification loop. When DCs were triggered with the potent synergistic combination of LPS (TLR4) and R848 (TLR7/8) in conjunction with a TLR2 ligand, a clear shift to more Th2- and Th17-prone responses in the naive and memory T cell subpopulations was observed. This shift in T cell responses was inherent to the inability of TLR2-stimulated DCs to produce IL-12p70 and was dependent on the production of IL-1 and IL-6.

Contains fulltext : 35219.pdf (publisher's version ) (Closed access), OBJECTIVE: Fcgamma receptors (FcgammaRs) recognize immune complexes (ICs) and coordinate the immune response by modulating the functions of dendritic cells (DCs). The purpose of this study was to unravel the role of the inhibitory FcgammaRIIb in rheumatoid arthritis (RA) by studying the effect of the FCGR2B 695T>C polymorphism on susceptibility to RA, severity of the disease, and DC function. METHODS: Genotyping was performed in RA patients (n = 246) and healthy blood donors (n = 269). The patients' demographic data, disease severity, and disease progression were assessed over a followup of 6 years. DCs were cultured for flow cytometry to determine the expression of FcgammaRs. For detection of FcgammaRIIb (CD32B), a unique anti-FcgammaRIIb antibody (2B6-fluorescein isothiocyanate [FITC]) was used. The capacity for antigen uptake by DCs was studied by assessing the uptake of FITC-labeled ICs. Levels of cytokine production by DCs were measured during lipopolysaccharide-mediated cell activation in the presence and absence of ICs. RESULTS: Although no role of the FCGR2B variant in RA susceptibility was demonstrated, this variant was associated with a nearly doubled rate of radiologic joint damage during the first 6 years of RA. Multiple regression analysis showed that FCGR2B was by far the strongest predictor of joint damage identified to date. DCs from patients carrying this variant failed to display the inhibitory phenotype normally observed upon IC-mediated triggering of inflammation and displayed diminished FcgammaRII-mediated antigen uptake compared with wild-type DCs. However, the levels of FcgammaRs were not affected, suggesting that the FCGR2B variant alters the function rather than regulation of proteins. CONCLUSION: This study is the first to show that a single genetic variant, the FCGR2B 695T>C polymorphism, is a critical determinant of disease severity in RA and radically changes DC behavior. Our results underscore the key role of DCs in the progression of R

Contains fulltext : 48417.pdf (publisher's version ) (Closed access), BACKGROUND: Dendritic cell (DC) function is largely tailored by Fc gamma receptors (Fc gamma R) and is critical for every immune response. OBJECTIVE: To compare interleukin (IL) 13 mediated regulation of Fc gamma RII and its related DC function between healthy controls and patients with rheumatoid arthritis (RA). METHODS: DC were derived from peripheral blood mononuclear cells according to standardised protocols. F cgammaRI, II, and III expression and DC phenotype were assessed by FACS analysis. The level of cytokine production and chemokine expression was measured by Luminex and real time quantitative polymerase chain reaction techniques. Antigen uptake capacity was studied by DC fluorescent heat aggregated immunoglobulins and FACS analysis. RESULTS: Replacement of IL4 by IL13 clearly increased the expression of Fc gamma RII on DC from healthy controls (CDC), but had no effect on DC from patients with RA (RADC). The lower production of inflammatory mediators by IL13 CDC upon Fc gamma R mediated triggering suggests that IL13 induces up regulation of specifically Fc gamma RII. RADC co-cultured with IL4 already displayed an inhibitory DC phenotype, but this inhibitory phenotype was not augmented by the addition of IL13. The defective Fc gamma RII regulation was further substantiated by the finding that IL13 CDC increased antigen uptake capacity, whereas IL13 RADC did not. CONCLUSION: IL13 regulates the expression of inhibitory Fc gamma RII in normal subjects but not in RA, potentially resulting in a chronic proinflammatory immune reaction in RA. Unravelling the underlying mechanisms of Fc gamma RII regulation might lead to new therapeutic targets in RA.