Publications by authors named "Mirjam Kool"

67 Publications

Loss of immune homeostasis in patients with idiopathic pulmonary arterial hypertension.

Thorax 2021 May 7. Epub 2021 May 7.

Department of Pulmonary Medicine, Erasmus Universiteit Rotterdam, Rotterdam, The Netherlands

Introduction: Autoreactivity against pulmonary vascular structures is thought to be involved in idiopathic pulmonary arterial hypertension (IPAH), but the underlying mechanisms remain poorly understood. We hypothesised that aberrant B-cell activation contributes to IPAH aetiology.

Methods: Mice with enhanced B-cell activation due to B-cell-specific overexpression of the B-cell receptor (BCR) signalling molecule Bruton's tyrosine kinase (BTK) were subjected to lung injury and examined for several pulmonary hypertension (PH) indices. Peripheral blood lymphocytes from patients with IPAH (n=13), connective tissue disease-associated PAH (CTD-PAH, n=9), congenital heart disease PAH (n=7), interstitial lung disease associated PH (n=17) and healthy controls (n=19) were characterised by 14-colour flow cytometry.

Results: Following pulmonary injury, BTK-overexpressing mice showed prolonged activation of B cells and CXCR5 follicular T-helper (Tfh) cells, as well as features of PH development. Patients with CTD-PAH and CHD-PAH displayed reduced proportions of circulating non-switched-memory B cells (p=0.03, p=0.02, respectively). Interestingly, we observed increased BTK protein expression in naive (p=0.007) and memory B-cell subsets of patients with IPAH and CTD-PAH. BTK was particularly high in patients with IPAH with circulating autoantibodies (p=0.045). IPAH patients had low frequencies of circulating CXCR5 Tfh cells (p=0.005). Hereby, the increased BTK protein expression in B cells was associated with high proportions of Tfh17 (p=0.018) and Tfh17.1 (p=0.007) cells within the circulating Tfh population.

Conclusions: Our study shows that pulmonary injury in combination with enhanced B-cell activation is sufficient to induce PH symptoms in mice. In parallel, immune homeostasis in patients with IPAH is compromised, as evidenced by increased BCR signalling and cTfh17 polarisation, indicating that adaptive immune activation contributes to IPAH disease induction or progression.
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http://dx.doi.org/10.1136/thoraxjnl-2020-215460DOI Listing
May 2021

Central Role of Dendritic Cells in Pulmonary Arterial Hypertension in Human and Mice.

Int J Mol Sci 2021 Feb 10;22(4). Epub 2021 Feb 10.

Department of Pulmonary Medicine, Erasmus MC, University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands.

The pathogenesis of idiopathic pulmonary arterial hypertension (IPAH) is not fully understood, but evidence is accumulating that immune dysfunction plays a significant role. We previously reported that 31-week-old mice develop pulmonary hypertension (PH) symptoms. These mice harbor a targeted deletion of the TNFα-induced protein-3 () gene, encoding the NF-κB regulatory protein A20, specifically in type I conventional dendritic cells (cDC1s). Here, we studied the involvement of dendritic cells (DCs) in PH in more detail. We found various immune cells, including DCs, in the hearts of mice, particularly in the right ventricle (RV). Secondly, in young mice, innate immune activation through airway exposure to toll-like receptor ligands essentially did not result in elevated RV pressures, although we did observe significant RV hypertrophy. Thirdly, PH symptoms in mice were not enhanced by concomitant mutation of bone morphogenetic protein receptor type 2 (), which is the most affected gene in PAH patients. Finally, in human IPAH lung tissue we found co-localization of DCs and CD8+ T cells, representing the main cell type activated by cDC1s. Taken together, these findings support a unique role of cDC1s in PAH pathogenesis, independent of general immune activation or a mutation in the gene.
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http://dx.doi.org/10.3390/ijms22041756DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7916474PMC
February 2021

Design of a randomized controlled trial to evaluate effectiveness of methotrexate versus prednisone as first-line treatment for pulmonary sarcoidosis: the PREDMETH study.

BMC Pulm Med 2020 Oct 19;20(1):271. Epub 2020 Oct 19.

Department of Respiratory Medicine, Centre of Excellence for Interstitial Lung Diseases and Sarcoidosis, Erasmus Medical Center, Rotterdam, the Netherlands.

Background: Treatment of pulmonary sarcoidosis is recommended in case of significant symptoms, impaired or deteriorating lung function. Evidence-based treatment recommendations are limited and largely based on expert opinion. Prednisone is currently the first-choice therapy and leads to short-term improvement of lung function. Unfortunately, prednisone often has side-effects and may be associated with impaired quality of life. Methotrexate is presently considered second-line therapy, and appears to have fewer side-effects.

Objective: The primary objective of this trial is to investigate the effectiveness and tolerability of methotrexate as first-line therapy in patients with pulmonary sarcoidosis compared with prednisone. The primary endpoint of this study will be the change in hospital-measured Forced Vital Capacity (FVC) between baseline and 24 weeks. Secondary objectives are to gain more insights in response to therapy in individual patients by home spirometry and patient-reported outcomes. Blood biomarkers will be examined to find predictors of response to therapy, disease progression and chronicity, and to improve our understanding of the underlying disease mechanism.

Methods/design: In this prospective, randomized, non-blinded, multi-center, non-inferiority trial, we plan to randomize 138 treatment-naïve patients with pulmonary sarcoidosis who are about to start treatment. Patients will be randomized in a 1:1 ratio to receive either prednisone or methotrexate in a predefined schedule for 24 weeks, after which they will be followed up in regular care for up to 2 years. Regular hospital visits will include pulmonary function assessment, completion of patient-reported outcomes, and blood withdrawal. Additionally, patients will be asked to perform weekly home spirometry, and record symptoms and side-effects via a home monitoring application for 24 weeks.

Discussion: This study will be the first randomized controlled trial comparing first-line treatment of prednisone and methotrexate and provide valuable data on efficacy, safety, quality of life and biomarkers. If this study confirms the hypothesis that methotrexate is as effective as prednisone as first-line treatment for sarcoidosis but with fewer side-effects, this will lead to improvement in care and initiate a change in practice. Furthermore, insights into the immunological mechanisms underlying sarcoidosis pathology might reveal new therapeutic targets.

Trial Registration: The study was registered on the 19th of March 2020 in the International Clinical Trial Registry, www.clinicaltrials.gov; ID NCT04314193 .
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http://dx.doi.org/10.1186/s12890-020-01290-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7574228PMC
October 2020

NEUROlogical Prognosis After Cardiac Arrest in Kids (NEUROPACK) study: protocol for a prospective multicentre clinical prediction model derivation and validation study in children after cardiac arrest.

BMJ Open 2020 09 25;10(9):e037517. Epub 2020 Sep 25.

Birmingham Acute Care Research Group, University of Birmingham College of Medical and Dental Sciences, Birmingham, West Midlands, UK.

Introduction: Currently, we are unable to accurately predict mortality or neurological morbidity following resuscitation after paediatric out of hospital (OHCA) or in-hospital (IHCA) cardiac arrest. A clinical prediction model may improve communication with parents and families and risk stratification of patients for appropriate postcardiac arrest care. This study aims to the derive and validate a clinical prediction model to predict, within 1 hour of admission to the paediatric intensive care unit (PICU), neurodevelopmental outcome at 3 months after paediatric cardiac arrest.

Methods And Analysis: A prospective study of children (age: >24 hours and <16 years), admitted to 1 of the 24 participating PICUs in the UK and Ireland, following an OHCA or IHCA. Patients are included if requiring more than 1 min of cardiopulmonary resuscitation and mechanical ventilation at PICU admission Children who had cardiac arrests in PICU or neonatal intensive care unit will be excluded. Candidate variables will be identified from data submitted to the Paediatric Intensive Care Audit Network registry. Primary outcome is neurodevelopmental status, assessed at 3 months by telephone interview using the Vineland Adaptive Behavioural Score II questionnaire. A clinical prediction model will be derived using logistic regression with model performance and accuracy assessment. External validation will be performed using the Therapeutic Hypothermia After Paediatric Cardiac Arrest trial dataset. We aim to identify 370 patients, with successful consent and follow-up of 150 patients. Patient inclusion started 1 January 2018 and inclusion will continue over 18 months.

Ethics And Dissemination: Ethical review of this protocol was completed by 27 September 2017 at the Wales Research Ethics Committee 5, 17/WA/0306. The results of this study will be published in peer-reviewed journals and presented in conferences.

Trial Registration Number: NCT03574025.
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http://dx.doi.org/10.1136/bmjopen-2020-037517DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7520830PMC
September 2020

DNGR1-Cre-mediated Deletion of /A20 in Conventional Dendritic Cells Induces Pulmonary Hypertension in Mice.

Am J Respir Cell Mol Biol 2020 11;63(5):665-680

Department of Pulmonary Medicine.

Chronic perivascular inflammation is a prominent feature in the lungs of idiopathic pulmonary arterial hypertension. Although the proportions of conventional dendritic cells (cDCs) and plasmacytoid DCs are increased in idiopathic pulmonary arterial hypertension lungs, it remains unknown whether activated cDCs play a pathogenic role. The gene encodes the ubiquitin-binding protein A20, which is a negative regulator of NF-κB, critically involved in DC activation. Targeting of Tnfaip3/A20 in cDCs was achieved by (DNGR1)-Cre-mediated excision of the gene in mice. Mice were evaluated for signs of pulmonary hypertension (PH) using right heart catheterization, echocardiography, and measurement of the Fulton index. Inflammation was assessed by immunohistochemistry and flow cytometry. Pulmonary cDCs and monocyte-derived DCs from 31-week-old mice showed modulated expression of cell surface activation markers compared with mice. mice developed elevated right ventricular systolic pressure and right ventricular hypertrophy. The lungs of these mice displayed increased vascular remodeling and perivascular and peribronchial immune cell infiltration resembling tertiary lymphoid organs. Proportions of activated T cells and expression of IL-1β, IL-6, and IL-10 were enhanced in the lungs of mice. Autoreactive IgA and IgG1 was detected in BAL and autoreactive IgA recognizing pulmonary endothelial antigens was present in the serum of mice. All signs of PH were ameliorated in mice by antiIL-6 antibody treatment. These results indicate that activation of the NF-κB pathway in DCs, through deletion of A20/, leads to experimental PH with accompanied pulmonary inflammation in an IL-6-dependent fashion.
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http://dx.doi.org/10.1165/rcmb.2019-0443OCDOI Listing
November 2020

Tnfaip3 expression in pulmonary conventional type 1 Langerin-expressing dendritic cells regulates T helper 2-mediated airway inflammation in mice.

Allergy 2020 10 14;75(10):2587-2598. Epub 2020 Jun 14.

Department of Pulmonary Medicine, Erasmus MC, Rotterdam, The Netherlands.

Background: Conventional type 1 dendritic cells (cDC1s) control anti-viral and anti-tumor immunity by inducing antigen-specific cytotoxic CD8 T-cell responses. Controversy exists whether cDC1s also control CD4 T helper 2 (Th2) cell responses, since suppressive and activating roles have been reported. DC activation status, controlled by the transcription factor NF-κB, might determine the precise outcome of Th-cell differentiation upon encounter with cDC1s. To investigate the role of activated cDC1s in Th2-driven immune responses, pulmonary cDC1s were activated by targeted deletion of A20/Tnfaip3, a negative regulator of NF-κB signaling.

Methods: To target pulmonary cDC1s, Cd207 (Langerin)-mediated excision of A20/Tnfaip3 was used, generating Tnfaip3 xCd207 (Tnfaip3 ) mice. Mice were exposed to house dust mite (HDM) to provoke Th2-mediated immune responses.

Results: Mice harboring Tnfaip3-deficient cDC1s did not develop Th2-driven eosinophilic airway inflammation upon HDM exposure, but rather showed elevated numbers of IFNγ-expressing CD8 T cells. In addition, Tnfaip3 mice harbored increased numbers of IL-12-expressing cDC1s and elevated PD-L1 expression in all pulmonary DC subsets. Blocking either IL-12 or IFNγ in Tnfaip3 mice restored Th2 responses, whereas administration of recombinant IFNγ during HDM sensitization in C57Bl/6 mice blocked Th2 development.

Conclusions: These findings indicate that the activation status of cDC1s, shown by their specific expression of co-inhibitory molecules and cytokines, critically contributes to the development of Th2 cell-mediated disorders, most likely by influencing IFNγ production in CD8 T cells.
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http://dx.doi.org/10.1111/all.14334DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7687104PMC
October 2020

Pulmonary Arterial Hypertension and Chronic Thromboembolic Pulmonary Hypertension: An Immunological Perspective.

J Clin Med 2020 Feb 19;9(2). Epub 2020 Feb 19.

Department of Pulmonary Medicine, Erasmus MC, Doctor Molenwaterplein 40, 3015 GD Rotterdam, The Netherlands.

Pulmonary hypertension (PH) is a debilitating progressive disease characterized by increased pulmonary arterial pressures, leading to right ventricular (RV) failure, heart failure and, eventually, death. Based on the underlying conditions, PH patients can be subdivided into the following five groups: (1) pulmonary arterial hypertension (PAH), (2) PH due to left heart disease, (3) PH due to lung disease, (4) chronic thromboembolic PH (CTEPH), and (5) PH with unclear and/or multifactorial mechanisms Currently, even with PAH-specific drug treatment, prognosis for PAH and CTEPH patients remains poor, with mean five-year survival rates of 57%-59% and 53%-69% for PAH and inoperable CTEPH, respectively. Therefore, more insight into the pathogenesis of PAH and CTEPH is highly needed, so that new therapeutic strategies can be developed. Recent studies have shown increased presence and activation of innate and adaptive immune cells in both PAH and CTEPH patients. Moreover, extensive biomarker research revealed that many inflammatory and immune markers correlate with the hemodynamics and/or prognosis of PAH and CTEPH patients. Increased evidence of the pathological role of immune cells in innate and adaptive immunity has led to many promising pre-clinical interventional studies which, in turn, are leading to innovative clinical trials which are currently being performed. A combination of immunomodulatory therapies might be required besides current treatment based on vasodilatation alone, to establish an effective treatment and prevention of progression for this disease. In this review, we describe the recent progress on our understanding of the involvement of the individual cell types of the immune system in PH. We summarize the accumulating body of evidence for inflammation and immunity in the pathogenesis of PH, as well as the use of inflammatory biomarkers and immunomodulatory therapy in PAH and CTEPH.
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http://dx.doi.org/10.3390/jcm9020561DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7074374PMC
February 2020

Epinephrine in paediatric bradycardic cardiac arrest: Time for a rethink?

Resuscitation 2020 04 21;149:230-232. Epub 2020 Feb 21.

Birmingham Women & Children's Hospital NHS Foundation Trust, UK; Birmingham Acute Care Research Group, Institute of Inflammation and Ageing, University of Birmingham, UK. Electronic address:

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http://dx.doi.org/10.1016/j.resuscitation.2020.02.015DOI Listing
April 2020

Enhanced Bruton's tyrosine kinase in B-cells and autoreactive IgA in patients with idiopathic pulmonary fibrosis.

Respir Res 2019 Oct 24;20(1):232. Epub 2019 Oct 24.

Department of Pulmonary Medicine, Erasmus Medical Center, 's-Gravendijkwal 230, 3015, CE, Rotterdam, The Netherlands.

Rationale: Idiopathic Pulmonary Fibrosis (IPF) is thought to be triggered by repeated alveolar epithelial cell injury. Current evidence suggests that aberrant immune activation may contribute. However, the role of B-cell activation remains unclear. We determined the phenotype and activation status of B-cell subsets and evaluated the contribution of activated B-cells to the development of lung fibrosis both in humans and in mice.

Methods: B-cells in blood, mediastinal lymph node, and lung single-cell suspensions of IPF patients and healthy controls (HC) were characterized using 14-color flow cytometry. Mice were exposed to bleomycin to provoke pulmonary fibrosis.

Results: More IgA memory B-cells and plasmablasts were found in blood (n = 27) and lungs (n = 11) of IPF patients compared to HC (n = 21) and control lungs (n = 9). IPF patients had higher levels of autoreactive IgA in plasma, which correlated with an enhanced decline of forced vital capacity (p = 0.002, r = - 0.50). Bruton's tyrosine kinase expression was higher in circulating IPF B-cells compared to HC, indicating enhanced B-cell activation. Bleomycin-exposed mice had increased pulmonary IgA germinal center and plasma cell proportions compared to control mice. The degree of lung fibrosis correlated with pulmonary germinal center B-cell proportions (p = 0.010, r = 0.88).

Conclusion: Our study demonstrates that IPF patients have more circulating activated B-cells and autoreactive IgA, which correlate with disease progression. These B-cell alterations were also observed in the widely used mouse model of experimental pulmonary fibrosis. Autoreactive IgA could be useful as a biomarker for disease progression in IPF.
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http://dx.doi.org/10.1186/s12931-019-1195-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6814043PMC
October 2019

DNGR1-mediated deletion of A20/Tnfaip3 in dendritic cells alters T and B-cell homeostasis and promotes autoimmune liver pathology.

J Autoimmun 2019 08 9;102:167-178. Epub 2019 Jul 9.

Department of Pulmonary Medicine, Erasmus MC, PO Box 2040, 3000 CA, Rotterdam, the Netherlands. Electronic address:

Dendritic cells (DCs) are central regulators of tolerance versus immunity. The outcome depends amongst others on DC subset and activation status. Whereas CD11b type 2 conventional DCs (cDC2s) initiate proinflammatory helper T (Th)-cell responses, CD103 cDC1s are crucial for regulatory T-cell (Treg) induction and CD8 T-cell activation. DC activation is controlled by the transcription factor NF-κB. Ablation of A20/Tnfaip3, a critical regulator of NF-κB activation, in DCs leads to constitutive DC activation and development of systemic autoimmunity. We hypothesized that the activation status of cDCs controls the development of autoimmunity. To target cDCs, DNGR1(Clec9a)-cre-mediated excision of A20/Tnfaip3 was used through generation of Tnfaip3xClec9a (Tnfaip3) mice. Immune cell activation was evaluated at 31-weeks of age. We found that DNGR1-cre-mediated deletion of A20/Tnfaip3 resulted in liver pathology characterized by inflammatory infiltrates adjacent to the portal triads. Both cDC subsets as well as monocyte-derived DCs (moDCs) in Tnfaip3 livers harbored an activated phenotype. Specifically, the costimulatory molecule CD40 in liver cDCs and moDCs was regulated by A20/Tnfaip3 expression. Livers from Tnfaip3 mice had augmented proportions of Th1, Th17, Treg, and follicular Th (Tfh)-cells compared to control mice, accompanied by an increase in IgA-producing plasma cells. Serum IgA from Tnfaip3 mice recognized self-proteins, specifically cytoplasmic proteins in liver periportal regions. These data show that enhanced activation of cDCs and moDCs, due to A20/Tnfaip3 ablation, promotes the development of organ-specific autoimmunity but not systemic autoimmunity. This model could be useful to examine the pathobiological processes contributing to autoimmune liver diseases.
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http://dx.doi.org/10.1016/j.jaut.2019.05.007DOI Listing
August 2019

Dendritic Cell Subsets and Effector Function in Idiopathic and Connective Tissue Disease-Associated Pulmonary Arterial Hypertension.

Front Immunol 2019 22;10:11. Epub 2019 Jan 22.

Department of Pulmonary Medicine, Erasmus MC, Rotterdam, Netherlands.

Pulmonary arterial hypertension (PAH) is a cardiopulmonary disease characterized by an incurable condition of the pulmonary vasculature, leading to increased pulmonary vascular resistance, elevated pulmonary arterial pressure resulting in progressive right ventricular failure and ultimately death. PAH has different underlying causes. In approximately 30-40% of the patients no underlying risk factor or cause can be found, so-called idiopathic PAH (IPAH). Patients with an autoimmune connective tissue disease (CTD) can develop PAH [CTD-associated PAH (CTD-PAH)], suggesting a prominent role of immune cell activation in PAH pathophysiology. This is further supported by the presence of tertiary lymphoid organs (TLOs) near pulmonary blood vessels in IPAH and CTD-PAH. TLOs consist of myeloid cells, like monocytes and dendritic cells (DCs), T-cells, and B-cells. Next to their T-cell activating function, DCs are crucial for the preservation of TLOs. Multiple DC subsets can be found in steady state, such as conventional DCs (cDCs), including type 1 cDCs (cDC1s), and type 2 cDCs (cDC2s), AXLSiglec6 DCs (AS-DCs), and plasmacytoid DCs (pDCs). Under inflammatory conditions monocytes can differentiate into monocyte-derived-DCs (mo-DCs). DC subset distribution and activation status play an important role in the pathobiology of autoimmune diseases and most likely in the development of IPAH and CTD-PAH. DCs can contribute to pathology by activating T-cells (production of pro-inflammatory cytokines) and B-cells (pathogenic antibody secretion). In this review we therefore describe the latest knowledge about DC subset distribution, activation status, and effector functions, and polymorphisms involved in DC function in IPAH and CTD-PAH to gain a better understanding of PAH pathology.
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http://dx.doi.org/10.3389/fimmu.2019.00011DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6349774PMC
December 2019

Nebulised hypertonic saline in children with bronchiolitis admitted to the paediatric intensive care unit: A retrospective study.

J Paediatr Child Health 2019 Sep 6;55(9):1125-1132. Epub 2019 Jan 6.

Department of Paediatrics, University of Antwerp, Edegem, Belgium.

Aim: Bronchiolitis is one of the most common lower respiratory tract infections in young children, associated with significant morbidity, but limited therapeutic options. Nebulised hypertonic saline (HS) has been a supportive treatment until current guidelines advised against its routine use. Accordingly, the University Hospital of Antwerp recently changed their policies to stop using it, allowing us to evaluate retrospectively if HS influences the duration of respiratory support. Because, to our knowledge, the effect of HS on children with severe bronchiolitis admitted to a paediatric intensive care unit (PICU) has not been studied yet, we aimed to investigate the effect in this specific patient group.

Methods: Retrospective study including children up to the age of 2, admitted to the PICU with bronchiolitis from October 2013 until March 2016. The primary end point is the duration of respiratory support, including high flow nasal cannula, continuous positive airway pressure and invasive ventilation.

Results: A total of 104 children admitted to the PICU with bronchiolitis were included, with an average age of 3.4 months. In respiratory syncytial virus (RSV) positive patients, the use of nebulised HS was correlated with a decrease in the duration of respiratory support and the length of stay by factors 0.72 (P = 0.01) and 0.81 (P = 0.04), respectively.

Conclusions: A significant correlation was found between the use of HS and a decreased duration of respiratory support and admission in the PICU in patients with RSV bronchiolitis. This finding may warrant new prospective studies investigating HS specifically in children with severe bronchiolitis.
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http://dx.doi.org/10.1111/jpc.14371DOI Listing
September 2019

Targeting interleukin-13 in idiopathic pulmonary fibrosis: from promising path to dead end.

Eur Respir J 2018 12 13;52(6). Epub 2018 Dec 13.

National Reference Center for Rare Pulmonary Disease, Louis Pradel Hospital; UMR754, Claude Bernard University, Lyon, France.

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http://dx.doi.org/10.1183/13993003.02111-2018DOI Listing
December 2018

House dust mite-driven neutrophilic airway inflammation in mice with TNFAIP3-deficient myeloid cells is IL-17-independent.

Clin Exp Allergy 2018 12 27;48(12):1705-1714. Epub 2018 Sep 27.

Department of Pulmonary Medicine, Erasmus MC, Rotterdam, The Netherlands.

Background: Asthma is a heterogeneous disease of the airways that involves several types of granulocytic inflammation. Recently, we have shown that the activation status of myeloid cells regulated by TNFAIP3/A20 is a crucial determinant of eosinophilic or neutrophilic airway inflammation. However, whether neutrophilic inflammation observed in this model is dependent on IL-17 remains unknown.

Objective: In this study, we investigated whether IL-17RA-signalling is essential for eosinophilic or neutrophilic inflammation in house dust mite (HDM)-driven airway inflammation.

Methods: Tnfaip3 xLyz2 (Tnfaip3 ) mice were crossed to Il17ra mice, generating Tnfaip3 Il17ra mice and subjected to an HDM-driven airway inflammation model.

Results: Both eosinophilic and neutrophilic inflammation observed in HDM-exposed WT and Tnfaip3 mice respectively were unaltered in the absence of IL-17RA. Production of IL-5, IL-13 and IFN-γ by CD4 T cells was similar between WT, Tnfaip3 and Il17ra mice, whereas mucus-producing cells in Tnfaip3 Il17ra mice were reduced compared to controls. Strikingly, spontaneous accumulation of pulmonary Th1, Th17 and γδ-17 T cells was observed in Tnfaip3 Il17ra mice, but not in the other genotypes. Th17 cell-associated cytokines such as GM-CSF and IL-22 were increased in the lungs of HDM-exposed Tnfaip3 Il17ra mice, compared to IL-17RA-sufficient controls. Moreover, neutrophilic chemo-attractants CXCL1, CXCL2, CXCL12 and Th17-promoting cytokines IL-1β and IL-6 were unaltered between Tnfaip3 and Tnfaip3 Il17ra mice.

Conclusion And Clinical Relevance: These findings show that neutrophilic airway inflammation induced by activated TNFAIP3/A20-deficient myeloid cells can develop in the absence of IL-17RA-signalling. Neutrophilic inflammation is likely maintained by similar quantities of pro-inflammatory cytokines IL-1β and IL-6 that can, independently of IL-17-signalling, induce the expression of neutrophil chemo-attractants.
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http://dx.doi.org/10.1111/cea.13262DOI Listing
December 2018

A20/Tumor Necrosis Factor α-Induced Protein 3 in Immune Cells Controls Development of Autoinflammation and Autoimmunity: Lessons from Mouse Models.

Front Immunol 2018 21;9:104. Epub 2018 Feb 21.

Department of Pulmonary Medicine, Erasmus MC, Rotterdam, Netherlands.

Immune cell activation is a stringently regulated process, as exaggerated innate and adaptive immune responses can lead to autoinflammatory and autoimmune diseases. Perhaps the best-characterized molecular pathway promoting cell activation is the nuclear factor-κB (NF-κB) signaling pathway. Stimulation of this pathway leads to transcription of numerous pro-inflammatory and cell-survival genes. Several mechanisms tightly control NF-κB activity, including the key regulatory zinc finger (de)ubiquitinating enzyme A20/tumor necrosis factor α-induced protein 3 (TNFAIP3). Single nucleotide polymorphisms (SNPs) in the vicinity of the gene are associated with a spectrum of chronic systemic inflammatory diseases, indicative of its clinical relevance. Mice harboring targeted cell-specific deletions of the gene in innate immune cells such as macrophages spontaneously develop autoinflammatory disease. When immune cells involved in the adaptive immune response, such as dendritic cells or B-cells, are targeted for A20/TNFAIP3 deletion, mice develop spontaneous inflammation that resembles human autoimmune disease. Therefore, more knowledge on A20/TNFAIP3 function in cells of the immune system is beneficial in our understanding of autoinflammation and autoimmunity. Using the aforementioned mouse models, novel A20/TNFAIP3 functions have recently been described including control of necroptosis and inflammasome activity. In this review, we discuss the function of the A20/TNFAIP3 enzyme and its critical role in various innate and adaptive immune cells. Finally, we discuss the latest findings on SNPs in human autoinflammatory and autoimmune diseases and address that genotyping of SNPs may guide treatment decisions.
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http://dx.doi.org/10.3389/fimmu.2018.00104DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5826380PMC
March 2019

Increased T-helper 17.1 cells in sarcoidosis mediastinal lymph nodes.

Eur Respir J 2018 03 1;51(3). Epub 2018 Mar 1.

Dept of Pulmonary Medicine, Erasmus MC, Rotterdam, The Netherlands

The lung-draining mediastinal lymph nodes (MLNs) are currently widely used to diagnose sarcoidosis. We previously reported that T-helper (Th) 17.1 cells are responsible for the exaggerated interferon-γ production in sarcoidosis lungs. In this study, we aimed to investigate 1) whether Th17.1 cells are also increased in the MLNs of sarcoidosis patients and 2) whether frequencies of the Th17.1 cells at diagnosis may correlate with disease progression.MLN cells from treatment-naive pulmonary sarcoidosis patients (n=17) and healthy controls (n=22) and peripheral blood mononuclear cells (n=34) and bronchoalveolar lavage fluid (BALF) (n=36) from sarcoidosis patients were examined for CD4 T-cell subset proportions using flow cytometry.Higher proportions of Th17.1 cells were detected in sarcoidosis MLNs than in control MLNs. Higher Th17.1 cell proportions were found in sarcoidosis BALF compared with MLNs and peripheral blood. Furthermore, BALF Th17.1 cell proportions were significantly higher in patients developing chronic disease than in patients undergoing resolution within 2 years of clinical follow-up.These data suggest that Th17.1 cell proportions in pulmonary sarcoidosis can be evaluated as a diagnostic and/or prognostic marker in clinical practice and could serve as a new therapeutic target.
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http://dx.doi.org/10.1183/13993003.01124-2017DOI Listing
March 2018

Integrating Patient Perspectives into Personalized Medicine in Idiopathic Pulmonary Fibrosis.

Front Med (Lausanne) 2017 20;4:226. Epub 2017 Dec 20.

Department of Respiratory Medicine, Erasmus Medical Center, University Hospital Rotterdam, Rotterdam, Netherlands.

Idiopathic pulmonary fibrosis (IPF) is a progressive and ultimately fatal disease which has a major impact on patients' quality of life (QOL). Except for lung transplantation, there is no curative treatment option. Fortunately, two disease-modifying drugs that slow down disease decline were recently approved. Though this is a major step forward, these drugs do not halt or reverse the disease, nor convincingly improve health-related QOL. In daily practice, disease behavior and response to therapy greatly vary among patients. It is assumed that this is related to the multiple biological pathways and complex interactions between genetic, molecular, and environmental factors that are involved in the pathogenesis of IPF. Recently, research in IPF has therefore started to focus on developing targeted therapy through identifying genetic risk factors and biomarkers. In this rapidly evolving field of personalized medicine, patient factors such as lifestyle, comorbidities, preferences, and experiences with medication should not be overlooked. This review describes recent insights and methods on how to integrate patient perspectives into personalized medicine. Furthermore, it provides an overview of the most used patient-reported outcome measures in IPF, to facilitate choices for both researchers and clinicians when incorporating the patient voice in their research and care. To enhance truly personalized treatment in IPF, biology should be combined with patient perspectives.
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http://dx.doi.org/10.3389/fmed.2017.00226DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5742327PMC
December 2017

Th17-lineage cells in pulmonary sarcoidosis and Löfgren's syndrome: Friend or foe?

J Autoimmun 2018 02 5;87:82-96. Epub 2018 Jan 5.

Department of Pulmonary Medicine, Erasmus MC, Rotterdam, The Netherlands. Electronic address:

Sarcoidosis, a multisystem granulomatous disorder, has historically been classified as Th1-driven disease. However, increasing data demonstrate a key role of Th17-cell plasticity in granuloma formation and maintenance. In Löfgren's syndrome (LS), an acute and distinct phenotype of sarcoidosis with a favorable outcome, differences in Th17-lineage cell subsets, cytokine expression and T-cell suppressive mechanisms may account for differences in clinical presentation as well as prognosis compared to non-LS sarcoidosis. In contrast with LS, up to 20% of non-LS sarcoidosis patients may progress to irreversible pulmonary fibrosis. In non-LS sarcoidosis patients, IFN-γ-producing Th17.1-cells appear to be more pathogenic and possibly linked to disease progression, while a broader range of cytokines is found in bronchoalveolar lavage fluid (BALF) in LS patients. Differences in Cytotoxic T-lymphocyte antigen 4 (CTLA-4) expression on Th17-cells and regulatory T-cells (Treg) could contribute to Th17-cell pathogenicity and consequently to either disease resolution or ongoing inflammation in sarcoidosis. Furthermore, several genes and SNPs are associated with disease susceptibility and outcome in sarcoidosis, the majority of which are involved in antigen presentation, T-cell activation or regulation of T-cell survival. Novel insights into the role of Th17-cells in the pathogenesis of both LS and non-LS sarcoidosis will unravel pathogenic and benign Th17-lineage cell function and drivers of Th17-cell plasticity. This will also help identify new treatment strategies for LS and non-LS sarcoidosis patients by altering Th17-cell activation, suppress conversion into more pathogenic subtypes, or influence cytokine signaling towards a beneficial signature of Th17-lineage cells. In this review, we summarize new insights into Th17-cell plasticity in the complex pathogenesis of sarcoidosis and connect these cells to the different disease phenotypes, discuss the role of genetic susceptibility and autoimmunity and focus on possible treatment strategies.
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http://dx.doi.org/10.1016/j.jaut.2017.12.012DOI Listing
February 2018

Group 2 Innate Lymphoid Cells Exhibit a Dynamic Phenotype in Allergic Airway Inflammation.

Front Immunol 2017 1;8:1684. Epub 2017 Dec 1.

Department of Pulmonary Medicine, Rotterdam, Netherlands.

Group 2 innate lymphoid cells (ILC2) are implicated in allergic asthma as an early innate source of the type 2 cytokines IL-5 and IL-13. However, their induction in house dust mite (HDM)-mediated airway inflammation additionally requires T cell activation. It is currently unknown whether phenotypic differences exist between ILC2s that are activated in a T cell-dependent or T cell-independent fashion. Here, we compared ILC2s in IL-33- and HDM-driven airway inflammation. Using flow cytometry, we found that surface expression levels of various markers frequently used to identify ILC2s were dependent on their mode of activation, highly variable over time, and differed between tissue compartments, including bronchoalveolar lavage (BAL) fluid, lung, draining lymph nodes, and spleen. Whereas IL-33-activated BAL fluid ILC2s exhibited an almost uniform CD25CD127T1/ST2ICOSKLRG1 phenotype, at a comparable time point after HDM exposure BAL fluid ILC2s had a very heterogeneous surface marker phenotype. A major fraction of HDM-activated ILC2s were CD25CD127T1/ST2 ICOSKLRG1, but nevertheless had the capacity to produce large amounts of type 2 cytokines. HDM-activated CD25 ILC2s in BAL fluid and lung rapidly reverted to CD25 ILC2s upon stimulation with IL-33. Genome-wide transcriptional profiling of BAL ILC2s revealed ~1,600 differentially expressed genes: HDM-stimulated ILC2s specifically expressed genes involved in the regulation of adaptive immunity through B and T cell interactions, whereas IL-33-stimulated ILC2s expressed high levels of proliferation-related and cytokine genes. In both airway inflammation models ILC2s were present in the lung submucosa close to epithelial cells, as identified by confocal microscopy. In chronic HDM-driven airway inflammation ILC2s were also found inside organized cellular infiltrates near T cells. Collectively, our findings show that ILC2s are phenotypically more heterogeneous than previously thought, whereby their surface marker and gene expression profile are highly dynamic.
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http://dx.doi.org/10.3389/fimmu.2017.01684DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5716969PMC
December 2017

No evidence found for an association between prednisone dose and FVC change in newly-treated pulmonary sarcoidosis.

Respir Med 2018 05 31;138S:S31-S37. Epub 2017 Oct 31.

Department of Pulmonary Medicine, Erasmus MC, Rotterdam, The Netherlands.

Background: Prednisone is used as first-line therapy for pulmonary sarcoidosis. What dosing strategy has the best balance between effect and side-effects is largely unknown. We analyzed change in forced vital capacity (FVC) and weight during different prednisone doses used in daily practice for treatment naïve pulmonary sarcoidosis patients.

Methods: Multilevel models were used to describe FVC and weight change over time. Correlations were calculated using linear regression models.

Results: Fifty-four patients were included. FVC changed over time (p < 0.001), with an average increase of 9.6% predicted (95% CI: 7.2 to 12.1) at 12 months. Weight changed significantly over time (p < 0.001), with an average increase of 4.3 kg (95% CI: 3.0 to 5.6) at 12 months. Although FVC and weight changed significantly over time, there was little correlation between prednisone dose and FVC change, while weight increase correlated significantly with cumulative prednisone dose at 24 months. In patients treated with a high cumulative prednisone dose, baseline FVC was on average lower (p = 0.001) compared to low dose treated patients, while no significant differences were observed in need for second/third-line therapy or number of exacerbations. A strategy leading to a low cumulative dose at 12 months was defined by rapid dose tapering to 10 mg/day within 3.5 months.

Conclusions: These results suggest that prednisone therapy aimed at improving or preserving FVC in newly- treated pulmonary sarcoidosis can often be reduced in dose, using a treatment regimen that is characterized by early dose tapering.
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http://dx.doi.org/10.1016/j.rmed.2017.10.022DOI Listing
May 2018

TNF-α-induced protein 3 levels in lung dendritic cells instruct T2 or T17 cell differentiation in eosinophilic or neutrophilic asthma.

J Allergy Clin Immunol 2018 05 6;141(5):1620-1633.e12. Epub 2017 Sep 6.

Department of Pulmonary Medicine, Erasmus MC, Rotterdam, The Netherlands. Electronic address:

Background: It is currently unknown why allergen exposure or environmental triggers in patients with mild-to-moderate asthma result in T2-mediated eosinophilic inflammation, whereas patients with severe asthma often present with T17-mediated neutrophilic inflammation. The activation state of dendritic cells (DCs) is crucial for both T2 and T17 cell differentiation and is mediated through nuclear factor κB activation. Ablation of TNF-α-induced protein 3 (TNFAIP3), one of the crucial negative regulators of nuclear factor κB activation in myeloid cells and DCs, was shown to control DC activation.

Objective: In this study we investigated the precise role of TNFAIP3 in myeloid cells for the development of T2- and T17-cell mediated asthma.

Methods: We exposed mice with conditional deletion of the Tnfaip3 gene in either myeloid cells (by using the lysozyme M [LysM] promotor) or specifically in DCs (by using the Cd11c promotor) to acute and chronic house dust mite (HDM)-driven asthma models.

Results: We demonstrated that reduced Tnfaip3 gene expression in DCs in either Tnfaip3 or Tnfaip3 mice dose-dependently controlled development of T17-mediated neutrophilic severe asthma in both acute and chronic HDM-driven models, whereas wild-type mice had a purely T2-mediated eosinophilic inflammation. TNFAIP3-deficient DCs induced HDM-specific T17 cell differentiation through increased expression of the T17-instructing cytokines IL-1β, IL-6, and IL-23, whereas HDM-specific T2 cell differentiation was hampered by increased IL-12 and IL-6 production.

Conclusions: These data show that the extent of TNFAIP3 expression in DCs controls T2/T17 cell differentiation. This implies that reducing DC activation could be a new pharmacologic intervention to treat patients with severe asthma who present with T17-mediated neutrophilic inflammation.
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http://dx.doi.org/10.1016/j.jaci.2017.08.012DOI Listing
May 2018

Dendritic Cell Subsets in Asthma: Impaired Tolerance or Exaggerated Inflammation?

Front Immunol 2017 9;8:941. Epub 2017 Aug 9.

Department of Pulmonary Medicine, Erasmus MC, Rotterdam, Netherlands.

Asthma is a prevalent chronic heterogeneous inflammatory disease of the airways, leading to reversible airway obstruction, in which various inflammatory responses can be observed. Mild to moderate asthma patients often present with a Th2-mediated eosinophilic inflammation whereas in severe asthma patients, a Th17-associated neutrophilic or combined Th2 and Th17-mediated eosinophilic/neutrophilic inflammation is observed. The differentiation of these effector Th2 and Th17-cells is induced by allergen-exposed dendritic cells (DCs) that migrate toward the lung draining lymph node. The DC lineage comprises conventional DCs (cDCs) and plasmacytoid DCs (pDCs), of which the cDC lineage consists of type 1 cDCs (cDC1s) and cDC2s. During inflammation, also monocytes can differentiate into so-called monocyte-derived DCs (moDCs). These DC subsets differ both in ontogeny, localization, and in their functional properties. New identification tools and the availability of transgenic mice targeting specific DC subsets enable the investigation of how these different DC subsets contribute to or suppress asthma pathogenesis. In this review, we will discuss mechanisms used by different DC subsets to elicit or hamper the pathogenesis of both Th2-mediated eosinophilic asthma and more severe Th17-mediated neutrophilic inflammation.
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http://dx.doi.org/10.3389/fimmu.2017.00941DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5552666PMC
August 2017

Perinatal Activation of the Interleukin-33 Pathway Promotes Type 2 Immunity in the Developing Lung.

Immunity 2016 12 6;45(6):1285-1298. Epub 2016 Dec 6.

Department of Pulmonary Medicine, Erasmus University Medical Center Rotterdam, Rotterdam 3015 GJ, the Netherlands; Laboratory of Immunoregulation and Mucosal Immunology, VIB Inflammation Research Center, Ghent 9050, Belgium; Department of Pulmonary Medicine, Ghent University, Ghent 9000, Belgium. Electronic address:

Allergic disease originates in early life and polymorphisms in interleukin-33 gene (IL33) and IL1RL1, coding for IL-33R and decoy receptor sST2, confer allergy risk. Early life T helper 2 (Th2) cell skewing and allergy susceptibility are often seen as remnants of feto-maternal symbiosis. Here we report that shortly after birth, innate lymphoid type 2 cells (ILC2s), eosinophils, basophils, and mast cells spontaneously accumulated in developing lungs in an IL-33-dependent manner. During the phase of postnatal lung alveolarization, house dust mite exposure further increased IL-33, which boosted cytokine production in ILC2s and activated CD11b dendritic cells (DCs). IL-33 suppressed IL-12p35 and induced OX40L in neonatal DCs, thus promoting Th2 cell skewing. Decoy sST2 had a strong preventive effect on asthma in the neonatal period, less so in adulthood. Thus, enhanced neonatal Th2 cell skewing to inhaled allergens results from postnatal hyperactivity of the IL-33 axis during a period of maximal lung remodeling.
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http://dx.doi.org/10.1016/j.immuni.2016.10.031DOI Listing
December 2016

GATA1-Deficient Dendritic Cells Display Impaired CCL21-Dependent Migration toward Lymph Nodes Due to Reduced Levels of Polysialic Acid.

J Immunol 2016 12 4;197(11):4312-4324. Epub 2016 Nov 4.

Department of Blood Cell Research, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, Amsterdam 1066CX, the Netherlands;

Dendritic cells (DCs) play a pivotal role in the regulation of the immune response. DC development and activation is finely orchestrated through transcriptional programs. GATA1 transcription factor is required for murine DC development, and data suggest that it might be involved in the fine-tuning of the life span and function of activated DCs. We generated DC-specific Gata1 knockout mice (Gata1-KO), which presented a 20% reduction of splenic DCs, partially explained by enhanced apoptosis. RNA sequencing analysis revealed a number of deregulated genes involved in cell survival, migration, and function. DC migration toward peripheral lymph nodes was impaired in Gata1-KO mice. Migration assays performed in vitro showed that this defect was selective for CCL21, but not CCL19. Interestingly, we show that Gata1-KO DCs have reduced polysialic acid levels on their surface, which is a known determinant for the proper migration of DCs toward CCL21.
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http://dx.doi.org/10.4049/jimmunol.1600103DOI Listing
December 2016

T-cell immunology in sarcoidosis: Disruption of a delicate balance between helper and regulatory T-cells.

Curr Opin Pulm Med 2016 09;22(5):476-83

Department of Pulmonary Medicine, Erasmus MC, Rotterdam, The Netherlands.

Purpose Of Review: Although the aetiology of sarcoidosis is not yet completely understood, immunological changes within the T-cell compartment are characteristic for an exaggerated antigen-driven immune response. In this review, we describe the most recent findings on T-cell subset responses and regulation in sarcoidosis. We discuss how future immunological research can advance the field to unravel pathobiological mechanisms of this intriguingly complex disease.

Recent Findings: Research into the field of T-cell plasticity has recently challenged the long-held T helper type 1 (Th1) paradigm in sarcoidosis and striking parallels with autoimmune disorders and common variable immunodeficiency were recognized. For instance, it was demonstrated that Th17.1-cells rather than Th1-cells are responsible for the exaggerated IFN-γ production in pulmonary sarcoidosis. Furthermore, impaired regulatory T-cell function and alterations within the expression of co-inhibitory receptors that control T-cell responses, such as PD-1, CTLA-4 and BTNL2, raise new questions regarding T-cell regulation in pulmonary sarcoidosis.

Summary: It becomes increasingly clear that Th17(.1)-cells and regulatory T-cells are key players in sarcoidosis T-cell immunology. New findings on plasticity and co-inhibitory receptor expression by these subsets help build a more comprehensive model for T-cell regulation in sarcoidosis and will finally shed light on the potential of new treatment modalities.
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http://dx.doi.org/10.1097/MCP.0000000000000303DOI Listing
September 2016

IFN-γ-Producing T-Helper 17.1 Cells Are Increased in Sarcoidosis and Are More Prevalent than T-Helper Type 1 Cells.

Am J Respir Crit Care Med 2016 06;193(11):1281-91

1 Division of Pulmonary and Critical Care, Department of Medicine.

Rationale: Pulmonary sarcoidosis is classically defined by T-helper (Th) cell type 1 inflammation (e.g., IFN-γ production by CD4(+) effector T cells). Recently, IL-17A-secreting cells have been found in lung lavage, invoking Th17 immunity in sarcoidosis. Studies also identified IL-17A-secreting cells that expressed IFN-γ, but their abundance as a percentage of total CD4(+) cells was either low or undetermined.

Objectives: Based on evidence that Th17 cells can be polarized to Th17.1 cells to produce only IFN-γ, our goal was to determine whether Th17.1 cells are a prominent source of IFN-γ in sarcoidosis.

Methods: We developed a single-cell approach to define and isolate major Th-cell subsets using combinations of chemokine receptors and fluorescence-activated cell sorting. We subsequently confirmed the accuracy of subset enrichment by measuring cytokine production.

Measurements And Main Results: Discrimination between Th17 and Th17.1 cells revealed very high percentages of Th17.1 cells in lung lavage in sarcoidosis compared with controls in two separate cohorts. No differences in Th17 or Th1 lavage cells were found compared with controls. Lung lavage Th17.1-cell percentages were also higher than Th1-cell percentages, and approximately 60% of Th17.1-enriched cells produced only IFN-γ.

Conclusions: Combined use of surface markers and functional assays to study CD4(+) T cells in sarcoidosis revealed a marked expansion of Th17.1 cells that only produce IFN-γ. These results suggest that Th17.1 cells could be misclassified as Th1 cells and may be the predominant producer of IFN-γ in pulmonary sarcoidosis, challenging the Th1 paradigm of pathogenesis.
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http://dx.doi.org/10.1164/rccm.201507-1499OCDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4910899PMC
June 2016

Impaired survival of regulatory T cells in pulmonary sarcoidosis.

Respir Res 2015 Sep 16;16:108. Epub 2015 Sep 16.

Department of Pulmonary Medicine, Erasmus MC, 's Gravendijkwal 230, 3015 CE, Rotterdam, The Netherlands.

Background: Impaired regulatory T cell (Treg) function is thought to contribute to ongoing inflammatory responses in sarcoidosis, but underlying mechanisms remain unclear. Moreover, it is not known if increased apoptotic susceptibility of Tregs may contribute to an impaired immunosuppressive function in sarcoidosis. Therefore, the aim of this study is to analyze proportions, phenotype, survival, and apoptotic susceptibility of Tregs in sarcoidosis.

Methods: Patients with pulmonary sarcoidosis (n = 58) were included at time of diagnosis. Tregs were analyzed in broncho-alveolar lavage fluid and peripheral blood of patients and healthy controls (HC).

Results: In sarcoidosis patients no evidence was found for a relative deficit of Tregs, neither locally nor systemically. Rather, increased proportions of circulating Tregs were observed, most prominently in patients developing chronic disease. Sarcoidosis circulating Tregs displayed adequate expression of FoxP3, CD25 and CTLA4. Remarkably, in sarcoidosis enhanced CD95 expression on circulating activated CD45RO(+) Tregs was observed compared with HC, and proportions of these cells were significantly increased. Specifically sarcoidosis Tregs--but not Th cells--showed impaired survival compared with HC. Finally, CD95L-mediated apoptosis was enhanced in sarcoidosis Tregs.

Conclusion: In untreated patients with active pulmonary sarcoidosis, Tregs show impaired survival and enhanced apoptotic susceptibility towards CD95L. Increased apoptosis likely contributes to the insufficient immunosuppressive function of sarcoidosis Tregs. Further research into this field will help determine whether improvement of Treg survival holds a promising new therapeutic approach for chronic sarcoidosis patients.
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http://dx.doi.org/10.1186/s12931-015-0265-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4574219PMC
September 2015