Publications by authors named "Berent J Prakken"

84 Publications

Establishing an international awareness day for paediatric rheumatic diseases: reflections from the inaugural World Young Rheumatic Diseases (WORD) Day 2019.

Pediatr Rheumatol Online J 2020 Sep 11;18(1):71. Epub 2020 Sep 11.

European Network for Children with Arthritis, Geneva, Switzerland.

There is a lack of awareness of paediatric rheumatic diseases (PRDs), among the public, and certain groups of healthcare professionals (HCPs), including general practitioners. To help improve international awareness and understanding of PRDs, World yOung Rheumatic Diseases (WORD) Day was established on 18 March 2019. Its aim was to raise awareness of PRDs and the importance of timely referral plus early diagnosis and access to appropriate treatment and support. A steering committee was established, and an external agency provided digital support. A social media campaign was launched in December 2018 to promote it, and analytics were used to measure its impact. Face-to-face and virtual events took place globally on or around WORD Day 2019, with 34 countries reporting events. Examples included lectures, social gatherings and media appearances. A total of 2585 and 660 individuals followed the official Facebook and Twitter accounts respectively, up until WORD Day. The official #WORDDay2019 hashtag was seen by 533,955 unique accounts on 18 March 2019 alone, with 3.3 million impressions. WORD Day 2019 was the first international campaign focused solely on PRDs. It demonstrated that despite awareness events being often resource-light, they can be implemented across a range of diverse settings. WORD Day has now become an annual global awareness event, facilitated by a growing network of patient, parent and professional community supporters.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12969-020-00465-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7488434PMC
September 2020

How a four-year-old boy connects healthcare, biomedical research and undergraduate education.

Nat Biotechnol 2019 09;37(9):1092-1095

Centre for Education, University Medical Centre Utrecht, Utrecht, The Netherlands.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41587-019-0245-5DOI Listing
September 2019

Preventing Translational Scientists From Extinction: The Long-Term Impact of a Personalized Training Program in Translational Medicine on the Careers of Translational Scientists.

Front Med (Lausanne) 2018 9;5:298. Epub 2018 Nov 9.

Center for Education, University Medical Center Utrecht, Utrecht, Netherlands.

Far too much biomedical research is wasted and ends in the so called "Valley of Death": the gap that exists between biomedical research and its clinical application. While the translational process requires collaboration between many disciplines, current translational medicine focuses on single disciplines. Therefore, educational pathways that integrate clinical and research skills in interdisciplinary and interprofessional contexts are needed. The Eureka institute (http://www.eurekainstitute.org/) was founded to address these issues. The institute organizes an annual 1-week international certificate course to educate professionals in the domains of translational medicine. This study set out to investigate the impact of the Eureka certificate course on the alumni, focusing on their ability to engage in translational activities and thus become more proficient translational professionals. An explanatory, mixed-methods study was executed. A questionnaire was distributed to collect quantitative data on the number of alumni who were able to apply what they learned during the Eureka course and engage in translational activities. Questionnaire data were also used to inform the semi-structured interviews that were conducted subsequently. Fifty-one percent of the alumni reported that participating in the Eureka course played a role in their decision to change to a different job or in the way they were accomplishing their everyday work. Ten conditions for change that either hampered or supported the Eureka alumni's engagement in translational research activities were identified. Further, the learning outcomes of the Eureka course that impacted the alumni's professional activities were explored using Personal Professional Theory (PPT). The insight that alumni gained in the full translational spectrum and stakeholders involved stimulated reflection on their own role within that pathway. Further, according to the alumni, the course provided them with the skills and confidence to pursue a career as translational professional. These learning outcomes, in combination with conditions that supported alumni's engagement in translational activities, such as supportive professional partners, opportunities to network or collaborate, and a translational work environment, contributed to the large number of alumni that were able to engage in translational activities.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fmed.2018.00298DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6237913PMC
November 2018

Children and young people get rheumatic disease too.

Lancet Child Adolesc Health 2019 01 23;3(1):8-9. Epub 2018 Nov 23.

Department of Paediatric Rheumatology, University Medical Center Utrecht, Utrecht 3508AB, Netherlands. Electronic address:

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/S2352-4642(18)30374-2DOI Listing
January 2019

PD-1+CD8+ T cells are clonally expanding effectors in human chronic inflammation.

J Clin Invest 2018 10 2;128(10):4669-4681. Epub 2018 Aug 2.

Department of Pediatrics, Laboratory of Translational Immunology, University Medical Center Utrecht, Utrecht, Netherlands.

Chronic inflammatory diseases are characterized by recurrent inflammatory attacks in the tissues mediated by autoreactive T cells. Identity and functional programming of CD8+ T cells at the target site of inflammation still remain elusive. One key question is whether, in these antigen-rich environments, chronic stimulation leads to CD8+ T cell exhaustion comparable to what is observed in infectious disease contexts. In the synovial fluid (SF) of juvenile idiopathic arthritis (JIA) patients, a model of chronic inflammation, an overrepresentation of PD-1+CD8+ T cells was found. Gene expression profiling, gene set enrichment analysis, functional studies, and extracellular flux analysis identified PD-1+CD8+ T cells as metabolically active effectors, with no sign of exhaustion. Furthermore, PD-1+CD8+ T cells were enriched for a tissue-resident memory (Trm) cell transcriptional profile and demonstrated increased clonal expansion compared with the PD-1- counterpart, suggesting antigen-driven expansion of locally adapted cells. Interestingly, this subset was also found increased in target tissues in other human chronic inflammatory diseases. These data indicate that local chronic inflammation drives the induction and expansion of CD8+ T cells endowed with potential detrimental properties. Together, these findings lay the basis for investigation of PD-1-expressing CD8+ T cell targeting strategies in human chronic inflammatory diseases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1172/JCI96107DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6159979PMC
October 2018

Effect of anticoagulants on 162 circulating immune related proteins in healthy subjects.

Cytokine 2018 06 28;106:114-124. Epub 2017 Oct 28.

Department of Pediatric Immunology, University Medical Center Utrecht, Utrecht, The Netherlands; Multiplex Core Facility, Laboratory of Translational Immunology, University Medical center Utrecht, Utrecht, The Netherlands. Electronic address:

Diagnosis of complex disease and response to treatment is often associated with multiple indicators, both clinical and laboratorial. With the use of biomarkers, various mechanisms have been unraveled which can lead to better and faster diagnosis, predicting and monitoring of response to treatment and new drug development. With the introduction of multiplex technology for immunoassays and the growing awareness of the role of immune-monitoring during new therapeutic interventions it is now possible to test large numbers of soluble mediators in small sample volumes. However, standardization of sample collection and laboratory assessments remains suboptimal. We developed a multiplex immunoassay for detection of 162 immune related proteins in human serum and plasma. The assay was split in panels depending on natural occurring concentrations with a maximum of 60 proteins. The aim of this study was to evaluate precision, accuracy, reproducibility and stability of proteins when repeated freeze-thaw cycles are performed of this in-house developed panel, as well as assessing the protein signature in plasma and serum using various anticoagulants. Intra-assay variance of each mediator was <10%. Inter-assay variance ranged between 1.6 and 37% with an average of 12.2%. Recoveries were similar for all mediators (mean 99.8 ± 2.6%) with a range between 89-107%. Next we measured all mediators in serum, EDTA plasma and sodium heparin plasma of 43 healthy control donors. Of these markers only 19 showed similar expression profiles in the 3 different matrixes. Only 5 mediators were effected by multiple freeze-thawing cycles. Principal component analysis revealed different coagulants cluster separately and that sodium heparin shows the most consistent profile.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cyto.2017.10.021DOI Listing
June 2018

Recommendations for collaborative paediatric research including biobanking in Europe: a Single Hub and Access point for paediatric Rheumatology in Europe (SHARE) initiative.

Ann Rheum Dis 2018 03 11;77(3):319-327. Epub 2017 Oct 11.

Division of Rheumatology, Department of Pediatrics, University Hospital Tuebingen, Tübingen, Germany.

Innovative research in childhood rheumatic diseases mandates international collaborations. However, researchers struggle with significant regulatory heterogeneity; an enabling European Union (EU)-wide framework is missing. The aims of the study were to systematically review the evidence for best practice and to establish recommendations for collaborative research. The Paediatric Rheumatology European Single Hub and Access point for paediatric Rheumatology in Europe (SHARE) project enabled a scoping review and expert discussion, which then informed the systematic literature review. Published evidence was synthesised; recommendations were drafted. An iterative review process and consultations with Ethics Committees and European experts for ethical and legal aspects of paediatric research refined the recommendations. SHARE experts and patient representatives vetted the proposed recommendations at a consensus meeting using Nominal Group Technique. Agreement of 80% was mandatory for inclusion. The systematic literature review returned 1319 records. A total of 223 full-text publications plus 22 international normative documents were reviewed; 85 publications and 16 normative documents were included. A total of 21 recommendations were established including general principles (1-3), ethics (4-7), paediatric principles (8 and 9), consent to paediatric research (10-14), paediatric databank and biobank (15 and 16), sharing of data and samples (17-19), and commercialisation and third parties (20 and 21). The refined recommendations resulted in an agreement of >80% for all recommendations. The SHARE initiative established the first recommendations for Paediatric Rheumatology collaborative research across borders in Europe. These provide strong support for an urgently needed European framework and evidence-based guidance for its implementation. Such changes will promote research in children with rheumatic diseases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1136/annrheumdis-2017-211904DOI Listing
March 2018

Embracing Complexity beyond Systems Medicine: A New Approach to Chronic Immune Disorders.

Front Immunol 2016 12;7:587. Epub 2016 Dec 12.

Laboratory of Medical Immunology, Department of Laboratory Medicine, Radboud University Medical Centre , Nijmegen , Netherlands.

In order to combat chronic immune disorders (CIDs), it is an absolute necessity to understand the bigger picture, one that goes beyond insights at a one-disease, molecular, cellular, and static level. To unravel this bigger picture we advocate an integral, cross-disciplinary approach capable of embracing the complexity of the field. This paper discusses the current knowledge on common pathways in CIDs including general psychosocial and lifestyle factors associated with immune functioning. We demonstrate the lack of more in-depth psychosocial and lifestyle factors in current research cohorts and most importantly the need for an all-encompassing analysis of these factors. The second part of the paper discusses the challenges of understanding immune system dynamics and effectively integrating all key perspectives on immune functioning, including the patient's perspective itself. This paper suggests the use of techniques from complex systems science in describing and simulating healthy or deviating behavior of the immune system in its biopsychosocial surroundings. The patient's perspective data are suggested to be generated by using specific narrative techniques. We conclude that to gain more insight into the behavior of the whole system and to acquire new ways of combatting CIDs, we need to construct and apply new techniques in the field of computational and complexity science, to an even wider variety of dynamic data than used in today's systems medicine.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fimmu.2016.00587DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5149516PMC
December 2016

Developing translational medicine professionals: the Marie Skłodowska-Curie action model.

J Transl Med 2016 11 29;14(1):329. Epub 2016 Nov 29.

The Hospital for Sick Children, Peter Gilgan Centre for Research and Learning, University of Toronto, Toronto, ON, Canada.

End goal of translational medicine is to combine disciplines and expertise to eventually promote improvement of the global healthcare system by delivering effective therapies to individuals and society. Well-trained experts of the translational medicine process endowed with profound knowledge of biomedical technology, ethical and clinical issues, as well as leadership and teamwork abilities are essential for the effective development of tangible therapeutic products for patients. In this article we focus on education and, in particular, we discuss how programs providing training on the broad spectrum of the translational medicine continuum have still a limited degree of diffusion and do not provide professional support and mentorship in the long-term, resulting in the lack of well established professionals of translational medicine (TMPs) in the scientific community. Here, we describe the Marie Skłodowska-Curie Actions program ITN-EUtrain (EUropean Translational tRaining for Autoimmunity & Immune manipulation Network) where training on the Translational Medicine machinery was integrated with education on professional and personal skills, mentoring, and a long-lasting network of TMPs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12967-016-1088-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5129597PMC
November 2016

Understanding inflammation in juvenile idiopathic arthritis: How immune biomarkers guide clinical strategies in the systemic onset subtype.

Eur J Immunol 2016 09;46(9):2068-77

Department of Pediatric Immunology, Wilhelmina Children's Hospital/UMC Utrecht, Utrecht, The Netherlands.

The translation of basic insight in immunological mechanisms underlying inflammation into clinical practice of inflammatory diseases is still challenging. Here we describe how-through continuous dialogue between bench and bedside-immunological knowledge translates into tangible clinical use in a complex inflammatory disease, juvenile idiopathic arthritis (JIA). Systemic JIA (sJIA) is an autoinflammatory disease, leading to the very successful use of IL-1 antagonists. Further immunological studies identified new immune markers for diagnosis, prediction of complications, response to and successful withdrawal of therapy. Myeloid related protein (MRP)8, MRP14, S100A12, and Interleukin-18 are already used daily in clinic as markers for active sJIA. For non-sJIA subtypes, HLA-B27, antinuclear-antibodies, rheumatoid factor, erythrocyte sedimentation rate, and C-reactive protein are still used for classification, prognosis or active disease. MRP8, MRP14, and S100A12 are now under study for clinical practice. We believe that with biomarkers, algorithms can soon be designed for the individual risk of disease, complications, damage, prediction of response to, and successful withdrawal of therapy. In that way, less time will be lost and less pain will be suffered by the patients. In this review, we describe the current status of immunological biomarkers used in diagnosis and treatment of JIA.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/eji.201546092DOI Listing
September 2016

Autoimmune disease-associated gene expression is reduced by BET-inhibition.

Genom Data 2016 Mar 7;7:14-7. Epub 2015 Nov 7.

Dept. of Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht 3584 CX, The Netherlands; Laboratory of Translational Immunology, University Medical Center Utrecht, Utrecht 3508 GA, The Netherlands; Division of Pediatrics, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht 3584 EA, The Netherlands.

For many autoimmune diseases, the underlying mechanism is still unknown. In order to get more insight into the etiology of autoimmune diseases, we recently published a study were we performed epigenetic profiling and RNA sequencing on CD4(+)CD45RO(+) T cells derived from the site of inflammation of Juvenile Idiopathic Arthritis (JIA) patients and compared this with healthy controls [1]. In this "Data in Brief", we focus on the analysis of our RNA sequencing data reported in this study, of which the raw and processed files can be found in GEO under GSE71595. We provide a detailed description of the downstream analysis, quality controls, and different analysis methods or techniques that validate the results obtained with RNA-sequencing.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.gdata.2015.11.004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4778599PMC
March 2016

Neonatal thymectomy reveals differentiation and plasticity within human naive T cells.

J Clin Invest 2016 Mar 22;126(3):1126-36. Epub 2016 Feb 22.

The generation of naive T cells is dependent on thymic output, but in adults, the naive T cell pool is primarily maintained by peripheral proliferation. Naive T cells have long been regarded as relatively quiescent cells; however, it was recently shown that IL-8 production is a signatory effector function of naive T cells, at least in newborns. How this functional signature relates to naive T cell dynamics and aging is unknown. Using a cohort of children and adolescents who underwent neonatal thymectomy, we demonstrate that the naive CD4+ T cell compartment in healthy humans is functionally heterogeneous and that this functional diversity is lost after neonatal thymectomy. Thymic tissue regeneration later in life resulted in functional restoration of the naive T cell compartment, implicating the thymus as having functional regenerative capacity. Together, these data shed further light on functional differentiation within the naive T cell compartment and the importance of the thymus in human naive T cell homeostasis and premature aging. In addition, these results affect and alter our current understanding on the identification of truly naive T cells and recent thymic emigrants.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1172/JCI84997DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4767338PMC
March 2016

Autologous stem cell transplantation aids autoimmune patients by functional renewal and TCR diversification of regulatory T cells.

Blood 2016 Jan 19;127(1):91-101. Epub 2015 Oct 19.

Laboratory of Translational Immunology, Department of Paediatric Immunology, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, The Netherlands;

Autologous hematopoietic stem cell transplantation (HSCT) is increasingly considered for patients with severe autoimmune diseases whose prognosis is poor with standard treatments. Regulatory T cells (Tregs) are thought to be important for disease remission after HSCT. However, eliciting the role of donor and host Tregs in autologous HSCT is not possible in humans due to the autologous nature of the intervention. Therefore, we investigated their role during immune reconstitution and re-establishment of immune tolerance and their therapeutic potential following congenic bone marrow transplantation (BMT) in a proteoglycan-induced arthritis (PGIA) mouse model. In addition, we determined Treg T-cell receptor (TCR) CDR3 diversity before and after HSCT in patients with juvenile idiopathic arthritis and juvenile dermatomyositis. In the PGIA BMT model, after an initial predominance of host Tregs, graft-derived Tregs started dominating and displayed a more stable phenotype with better suppressive capacity. Patient samples revealed a striking lack of diversity of the Treg repertoire before HSCT. This ameliorated after HSCT, confirming reset of the Treg compartment following HSCT. In the mouse model, a therapeutic approach was initiated by infusing extra Foxp3(GFP+) Tregs during BMT. Infusion of Foxp3(GFP+) Tregs did not elicit additional clinical improvement but conversely delayed reconstitution of the graft-derived T-cell compartment. These data indicate that HSCT-mediated amelioration of autoimmune disease involves renewal of the Treg pool. In addition, infusion of extra Tregs during BMT results in a delayed reconstitution of T-cell compartments. Therefore, Treg therapy may hamper development of long-term tolerance and should be approached with caution in the clinical autologous setting.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1182/blood-2015-06-649145DOI Listing
January 2016

Inhibition of Super-Enhancer Activity in Autoinflammatory Site-Derived T Cells Reduces Disease-Associated Gene Expression.

Cell Rep 2015 Sep 17;12(12):1986-96. Epub 2015 Sep 17.

Department of Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht 3584 CX, the Netherlands; Laboratory of Translational Immunology, University Medical Center Utrecht, Utrecht 3508 GA, the Netherlands; Division of Pediatrics, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht 3584 EA, the Netherlands. Electronic address:

The underlying molecular mechanisms for many autoimmune diseases are poorly understood. Juvenile idiopathic arthritis (JIA) is an exceptionally well-suited model for studying autoimmune diseases due to its early onset and the possibility to analyze cells derived from the site of inflammation. Epigenetic profiling, utilizing primary JIA patient-derived cells, can contribute to the understanding of autoimmune diseases. With H3K27ac chromatin immunoprecipitation, we identified a disease-specific, inflammation-associated, typical enhancer and super-enhancer signature in JIA patient synovial-fluid-derived CD4(+) memory/effector T cells. RNA sequencing of autoinflammatory site-derived patient T cells revealed that BET inhibition, utilizing JQ1, inhibited immune-related super-enhancers and preferentially reduced disease-associated gene expression, including cytokine-related processes. Altogether, these results demonstrate the potential use of enhancer profiling to identify disease mediators and provide evidence for BET inhibition as a possible therapeutic approach for the treatment of autoimmune diseases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.celrep.2015.08.046DOI Listing
September 2015

Self-Sustained Resistance to Suppression of CD8+ Teff Cells at the Site of Autoimmune Inflammation Can Be Reversed by Tumor Necrosis Factor and Interferon-γ Blockade.

Arthritis Rheumatol 2016 Jan;68(1):229-36

University Medical Center Utrecht, Utrecht, The Netherlands.

Objective: Resistance of Teff cells to Treg cell-mediated suppression contributes to the breakdown of peripheral tolerance in the inflamed joints of patients with juvenile idiopathic arthritis (JIA). However, unanswered questions are whether this resistant phenotype is self-sustained and whether CD8+ and CD4+ Teff cells share the same mechanism of resistance to suppression. We undertook this study to investigate intrinsic resistance of CD8+ Teff cells to suppression and to determine how this can be targeted therapeutically.

Methods: CD8+ or CD4+ Teff cells were cultured with or without antigen-presenting cells (APCs) in Treg cell-dependent and -independent suppression assays. Synovial fluid (SF)-derived Teff cells were crosscultured with peripheral blood (PB) Treg cells from JIA patients or healthy controls. Tumor necrosis factor (TNF) or interferon-γ (IFNγ) blocking agents were used to restore Teff cell responsiveness to suppression.

Results: Suppression of cell proliferation and cytokine production in CD8+ Teff cells from the SF of JIA patients was severely impaired compared to that in CD8+ Teff cells from the PB of JIA patients, regardless of the presence of APCs and CD4+ Teff cells. Similar to CD4+ Teff cells, impaired suppression of CD8+ Teff cells was shown to be an intrinsic feature of this cell population. While TNF blockade restored both CD8+ and CD4+ Teff cell susceptibility to suppression, autocrine release of IFNγ selectively sustained CD8+ Teff cell resistance, which could be relieved by IFNγ blockade.

Conclusion: Unlike CD4+ Teff cells, resistance of CD8+ Teff cells to suppression at the site of autoimmune inflammation is maintained by autocrine release of IFNγ, and blockade of IFNγ restores CD8+ Teff cell responsiveness to suppression. These findings indicate a potential therapeutic value of blocking IFNγ to restore immune regulation in JIA.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/art.39418DOI Listing
January 2016

Methotrexate treatment affects effector but not regulatory T cells in juvenile idiopathic arthritis.

Rheumatology (Oxford) 2015 Sep 14;54(9):1724-34. Epub 2015 Apr 14.

Center for Molecular and Cellular Intervention, Department of Pediatric Immunology, Wilhelmina Children's Hospital, University Medical Centre Utrecht, Utrecht, The Netherlands.

Objective: The balance between Treg and effector T cells (Teff) is crucial for immune regulation in JIA. How MTX, the cornerstone treatment in JIA, influences this balance in vivo is poorly elucidated. The aim of this study was to investigate quantitative and qualitative effects of MTX on Treg and Teff in JIA patients during MTX treatment.

Methods: Peripheral blood samples were obtained from JIA patients at the start of MTX and 3 and 6 months thereafter. Treg numbers and phenotypes were determined by flow cytometry and suppressive function in allogeneic suppression assays. Teff proliferation upon stimulation with anti-CD3, activation status and intracellular cytokine production were determined by flow cytometry. Effector cell responsiveness to suppression was investigated in autologous suppression assays. Effector cell cytokines in supernatants of proliferation and suppression assays and in plasma were measured by cytokine multiplex assay.

Results: MTX treatment in JIA did not affect Treg phenotype and function. Instead, MTX treatment enhanced, rather than diminished, CD4(+) and CD8(+) T cell proliferation of JIA patients after 6 months of therapy, independent of clinical response. Effector cells during MTX treatment were equally responsive to Treg-mediated suppression. MTX treatment did not attenuate Teff activation status and their capacity to produce IL-13, IL-17, TNF-α and IFN-γ. Similarly to Teff proliferation, plasma IFN-γ concentrations after 6 months were increased.

Conclusion: This study provides the novel insight that MTX treatment in JIA does not attenuate Teff function but, conversely, enhances T cell proliferation and IFN-γ plasma concentrations in JIA patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/rheumatology/kev101DOI Listing
September 2015

Paediatric rheumatic disease: Diagnosing macrophage activation syndrome in systemic JIA.

Nat Rev Rheumatol 2014 Nov 9;10(11):640-2. Epub 2014 Sep 9.

Center for Molecular and Cellular Intervention, Department of Pediatric Rheumatology and Immunology, University Medical Center Utrecht, PO Box 85090, 3508 AB Utrecht, Netherlands.

Macrophage activation syndrome (MAS) in systemic juvenile idiopathic arthritis (sJIA) is difficult to distinguish from active sJIA or sepsis. A collaborative effort scoring the performance of different clinical diagnostic criteria provides valuable guidance to clinicians, but challenges in the diagnosis of sJIA-related MAS remain.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/nrrheum.2014.143DOI Listing
November 2014

Increased presence of FOXP3+ regulatory T cells in inflamed muscle of patients with active juvenile dermatomyositis compared to peripheral blood.

PLoS One 2014 26;9(8):e105353. Epub 2014 Aug 26.

Laboratory of Translational Immunology, Pediatric Immunology, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, The Netherlands.

Juvenile dermatomyositis (JDM) is an immune-mediated inflammatory disease affecting the microvasculature of skin and muscle. CD4+ CD25+ FOXP3+ regulatory T cells (Tregs) are key regulators of immune homeostasis. A role for Tregs in JDM pathogenesis has not yet been established. Here, we explored Treg presence and function in peripheral blood and muscle of JDM patients. We analyzed number, phenotype and function of Tregs in blood from JDM patients by flow cytometry and in vitro suppression assays, in comparison to healthy controls and disease controls (Duchenne's Muscular Dystrophy). Presence of Tregs in muscle was analyzed by immunohistochemistry. Overall, Treg percentages in peripheral blood of JDM patients were similar compared to both control groups. Muscle biopsies of new onset JDM patients showed increased infiltration of numbers of T cells compared to Duchenne's muscular dystrophy. Both in JDM and Duchenne's muscular dystrophy the proportion of FOXP3+ T cells in muscles were increased compared to JDM peripheral blood. Interestingly, JDM is not a self-remitting disease, suggesting that the high proportion of Tregs in inflamed muscle do not suppress inflammation. In line with this, peripheral blood Tregs of active JDM patients were less capable of suppressing effector T cell activation in vitro, compared to Tregs of JDM in clinical remission. These data show a functional impairment of Tregs in a proportion of patients with active disease, and suggest a regulatory role for Tregs in JDM inflammation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0105353PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4144849PMC
May 2015

Effectiveness of first-line treatment with recombinant interleukin-1 receptor antagonist in steroid-naive patients with new-onset systemic juvenile idiopathic arthritis: results of a prospective cohort study.

Arthritis Rheumatol 2014 Apr;66(4):1034-43

University Medical Centre Utrecht, Utrecht, The Netherlands.

Objective: To conduct a prospective cohort study using anakinra, a recombinant IL-1 receptor antagonist (IL-1Ra), as first-line therapy in patients with new-onset systemic juvenile idiopathic arthritis (JIA).

Methods: Therapy with recombinant IL-1Ra (2 mg/kg) was initiated in 20 patients who fulfilled the International League of Associations for Rheumatology criteria for systemic JIA, before systemic steroid treatment was administered. Patients were monitored clinically and immunologically. The protocol contained a stop strategy for patients who met at least the adapted American College of Rheumatology 90% criteria for improvement in JIA (ACR Pediatric 90 [ACR Pedi 90]) after 3 months.

Results: We included consecutive patients with new-onset systemic JIA. The mean followup period was 32 months (range 12-54 months). At the 3-month time point, 85% of the patients showed an adapted ACR Pedi 90 response or had inactive disease; 75% of the patients achieved this response while receiving recombinant IL-1Ra alone. After 1 year, 17 of the 20 patients met the criteria for clinically inactive disease, and 13 of these patients met these criteria while receiving monotherapy with recombinant IL-1Ra. However, because of persistent disease activity, 7 of the 20 patients required additional therapy besides recombinant IL-1Ra. According to our stop strategy, 73% of patients with at least an adapted ACR Pedi 90 response at 3 months could stop recombinant IL-1Ra treatment within 1 year. After 2 years, 12 (86%) of 14 patients met the criteria for disease remission, either while receiving (n = 4) or not receiving (n = 8) medication. After 3 years, 10 (91%) of 11 patients met the criteria for disease remission, either while receiving (n = 2) or not receiving (n = 8) medication.

Conclusion: This is the first prospective study in which recombinant IL-1Ra was used as first-line therapy in patients with systemic JIA. We observed excellent responses in nearly all patients within 3 months. In the majority of responding patients, treatment with recombinant IL-1Ra could be stopped within 1 year, with remission being preserved during followup. In approximately one-third of patients, concomitant therapy was required for maintenance of clinical response.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/art.38296DOI Listing
April 2014

Brief report: Autologous stem cell transplantation restores immune tolerance in experimental arthritis by renewal and modulation of the Teff cell compartment.

Arthritis Rheumatol 2014 Feb;66(2):350-6

University Medical Center Utrecht and Wilhelmina Children's Hospital, Utrecht, The Netherlands.

Objective: Autologous stem cell transplantation (ASCT) induces long-term drug-free disease remission in patients with juvenile idiopathic arthritis. This study was undertaken to further unravel the immunologic mechanisms underlying ASCT by using a mouse model of proteoglycan-induced arthritis (PGIA).

Methods: For initiation of PGIA, BALB/c mice received 2 intraperitoneal injections of human PG in a synthetic adjuvant on days 0 and 21. Five weeks after the first immunization, the mice were exposed to total body irradiation (7.5 Gy) and received (un)manipulated bone marrow (BM) grafts from mice with PGIA. Clinical scores, T cell reconstitution, (antigen-specific) T cell cytokine production, and intracellular cytokine expression were determined following autologous BM transplantation (ABMT).

Results: ABMT resulted in amelioration and stabilization of arthritis scores. BM grafts containing T cells and T cell-depleted grafts provided the same clinical benefit, with similar reductions in PG-induced T cell proliferation and the number of PG-specific autoantibodies. In vivo reexposure to PG did not exacerbate disease. Following ABMT, basal levels of disease-associated proinflammatory cytokines (interferon-γ [IFNγ], interleukin-17 [IL-17], and tumor necrosis factor α [TNFα]) were reduced. In addition, restimulation of T cells with PG induced a strong reduction in disease-associated proinflammatory cytokine production. Finally, although the remaining host T cells displayed a proinflammatory phenotype following ABMT, IFNγ, IL-17, and TNFα production by the newly reconstituted donor-derived T cells was significantly lower.

Conclusion: Taken together, our data suggest that ABMT restores immune tolerance by renewal and modulation of the Teff cell compartment, leading to a strong reduction in proinflammatory (self antigen-specific) T cell cytokine production.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/art.38261DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4131556PMC
February 2014

T cell recognition of naturally presented epitopes of self-heat shock protein 70.

Cell Stress Chaperones 2014 Jul 15;19(4):569-78. Epub 2014 Jan 15.

Rheumatology and Clinical Immunology, University Medical Center Utrecht, Utrecht, The Netherlands.

Self-reactive T cells have shown to have a potential role as regulators of the immune system preventing or even suppressing autoimmunity. One of the most abundant proteins that can be eluted from human HLA molecules is heat shock protein 70 (HSP70). The aims of the current study are to identify HSP70 epitopes based on published HLA elution studies and to investigate whether T cells from healthy individuals may respond to such self-epitopes. A literature search and subsequent in silico binding prediction based on theoretical MHC binding motifs resulted in the identification of seven HSP70 epitopes. PBMCs of healthy controls proliferated after incubation with two of the seven peptides (H167 and H290). Furthermore H161, H290, and H443 induced CD69 expression or production of cytokines IFNγ or TNFα in healthy controls. The identification of these naturally presented epitopes and the response they elicit in the normal immune system make them potential candidates to study during inflammatory conditions as well as in autoimmune diseases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s12192-013-0484-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4041940PMC
July 2014

Plasma IL-25 is elevated in a subgroup of patients with clinical reactivity to peanut.

Clin Transl Allergy 2013 Dec 2;3(1):40. Epub 2013 Dec 2.

Laboratory for Translational Immunology, Department of Paediatric Immunology, University Medical Centre, PO BOX 85090, Utrecht 3508 AB, The Netherlands.

Background: One of the IL-17 family members, IL-25, has been implicated with the initiation and amplification of Th2 responses in animal models and has been associated with airway hyper-reactivity. The involvement of IL-25 and also IL-17 in food allergic disease remains to be investigated.

Findings: In this study thirty children suspected of peanut allergic disease underwent a double-blind placebo controlled food challenge (DBPCFC) and IL-25 and IL-17 plasma levels were determined before and after challenge. IL-25 was highly elevated only in subgroup of children with a positive DBPCFC outcome. Plasma IL-25 was absent in children with a negative DBPCFC outcome and in healthy controls.

Conclusions: This study shows that IL-25, an IL-17 family member, is highly elevated only in children with a clinical response to peanut. This suggests a role for IL-25 in the pathogenesis of peanut allergy and elevated plasma IL-25 may be a sign of a severe atopic phenotype.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/2045-7022-3-40DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4176502PMC
December 2013

TH17 differentiation capacity develops within the first 3 months of life.

J Allergy Clin Immunol 2014 Mar 1;133(3):891-4.e5. Epub 2013 Nov 1.

Center for Molecular and Cellular Intervention, Laboratory for Translational Immunology, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, The Netherlands. Electronic address:

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jaci.2013.09.022DOI Listing
March 2014

Differential homeostatic dynamics of human regulatory T-cell subsets following neonatal thymectomy.

J Allergy Clin Immunol 2014 Jan 18;133(1):277-80.e1-6. Epub 2013 Oct 18.

Department of Pediatric Immunology and the Laboratory of Translational Immunology, University Medical Center Utrecht, Utrecht, The Netherlands. Electronic address:

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jaci.2013.08.030DOI Listing
January 2014

Anti-tumor necrosis factor α targets protein kinase B/c-Akt-induced resistance of effector cells to suppression in juvenile idiopathic arthritis.

Arthritis Rheum 2013 Dec;65(12):3279-84

Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, The Netherlands.

Objective: To determine whether therapeutic strategies that block interleukin-6 (IL-6) or tumor necrosis factor α (TNFα) can improve the responsiveness of Teff cells to suppression in patients with juvenile idiopathic arthritis (JIA).

Methods: Synovial fluid mononuclear cells (SFMCs) from the inflamed joints of patients with JIA were cultured in the presence of etanercept or anti-IL-6 in vitro, and protein kinase B (PKB)/c-Akt activation and responsiveness to suppression were measured. In addition, the in vivo effects of TNFα blockade were investigated using peripheral blood mononuclear cells obtained from patients before and after the start of etanercept therapy.

Results: In vitro treatment of SFMCs with anti-IL-6 led to improved Treg cell-mediated suppression of cell proliferation in some but not all patients. Blocking TNFα with etanercept, however, clearly enhanced suppression, especially that of CD8+ T cells. In the presence of etanercept, PKB/c-Akt activation of Teff cells was reduced, and cells became more susceptible to transforming growth factor β-mediated suppression, indicating that anti-TNFα directly targets resistant Teff cells.

Conclusion: This study is the first to show that anti-TNFα targets the resistance of Teff cells to suppression, resulting in improved regulation of inflammatory effector cells.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/art.38132DOI Listing
December 2013

Stabilization of the transcription factor Foxp3 by the deubiquitinase USP7 increases Treg-cell-suppressive capacity.

Immunity 2013 Aug;39(2):259-71

Department of Immunology, University Medical Center Utrecht, Utrecht 3584EA, The Netherlands.

Stable Foxp3 expression is required for the development of functional regulatory T (Treg) cells. Here, we demonstrate that the expression of the transcription factor Foxp3 can be regulated through the polyubiquitination of multiple lysine residues, resulting in proteasome-mediated degradation. Expression of the deubiquitinase (DUB) USP7 was found to be upregulated and active in Treg cells, being associated with Foxp3 in the nucleus. Ectopic expression of USP7 decreased Foxp3 polyubiquitination and increased Foxp3 expression. Conversely, either treatment with DUB inhibitor or USP7 knockdown decreased endogenous Foxp3 protein expression and decreased Treg-cell-mediated suppression in vitro. Furthermore, in a murine adoptive-transfer-induced colitis model, either inhibition of DUB activity or USP7 knockdown in Treg cells abrogated their ability to resolve inflammation in vivo. Our data reveal a molecular mechanism in which rapid temporal control of Foxp3 expression in Treg cells can be regulated by USP7, thereby modulating Treg cell numbers and function.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.immuni.2013.05.018DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4133784PMC
August 2013

Canonical Wnt signaling negatively modulates regulatory T cell function.

Immunity 2013 Aug 15;39(2):298-310. Epub 2013 Aug 15.

Department of Immunology, University Medical Center Utrecht, Utrecht 3584EA, The Netherlands.

Foxp3 is crucial for both the development and function of regulatory T (Treg) cells; however, the posttranslational mechanisms regulating Foxp3 transcriptional output remain poorly defined. Here, we demonstrate that T cell factor 1 (TCF1) and Foxp3 associates in Treg cells and that active Wnt signaling disrupts Foxp3 transcriptional activity. A global chromatin immunoprecipitation sequencing comparison in Treg cells revealed considerable overlap between Foxp3 and Wnt target genes. The activation of Wnt signaling reduced Treg-mediated suppression both in vitro and in vivo, whereas disruption of Wnt signaling in Treg cells enhanced their suppressive capacity. The activation of effector T cells increased Wnt3a production, and Wnt3a levels were found to be greatly increased in mononuclear cells isolated from synovial fluid versus peripheral blood of arthritis patients. We propose a model in which Wnt produced under inflammatory conditions represses Treg cell function, allowing a productive immune response, but, if uncontrolled, could lead to the development of autoimmunity.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.immuni.2013.07.019DOI Listing
August 2013

Defective TH17 development in human neonatal T cells involves reduced RORC2 mRNA content.

J Allergy Clin Immunol 2013 Sep 29;132(3):754-756.e3. Epub 2013 May 29.

Department of Pediatric Immunology, Center for Molecular and Cellular Intervention CMCI, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, The Netherlands.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jaci.2013.04.014DOI Listing
September 2013

Cytokine assays: an assessment of the preparation and treatment of blood and tissue samples.

Methods 2013 May 19;61(1):10-7. Epub 2013 Apr 19.

Department of Pediatric Immunology (KC01.069.0), Centre for Molecular and Cellular Intervention, University Medical Centre Utrecht, Utrecht, The Netherlands.

Cytokines are key components of the innate and adaptive immune system. As pivotal players in the progression or regression of a pathological process, these molecules provide a window through which diseases can be monitored and can thus act as biomarkers. In order to measure cytokine levels, a plethora of protocols can be applied. These methods include bioassays, protein microarrays, high-performance liquid chromatography (HPLC), sandwich enzyme-linked immunosorbent assay (ELISA), Meso Scale Discovery (MSD) electrochemiluminescence and bead based multiplex immunoassays (MIA). Due to the interaction and activity of cytokines, multiplex immunoassays are at the forefront of cytokine analysis by allowing multiple cytokines to be measured in parallel. However, even with optimized protocols, sample standardization needs to occur before these proteins can optimally act as biomarkers. This review describes various factors influencing the levels of cytokines measured in plasma, serum, dried blood spots and tissue biopsies, focusing on sample collection and handling, long term storage and the repetitive use of samples. By analyzing how each of these factors influences protein levels, it is concluded that samples should be stored at low temperatures in order to maintain cytokine stability. In addition, within a study, sample manipulations should be kept the same, with measurement protocols being chosen for their compatibility with the research in question. By having a clear understanding of what factors influence cytokine levels and how to overcome these technical issues, minimally confounded data can be obtained and cytokines can achieve optimal biomarker activity.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ymeth.2013.04.005DOI Listing
May 2013