scholarly journals FRI0003 ELEVATED HISTONE H4 IN NEUTROPHIL EXTRACELLULAR TRAPS PROMOTES MACROPHAGE ACTIVATION IN BEHÇET’S DISEASE

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 572.1-573
Author(s):  
L. LI ◽  
X. Yu ◽  
J. Liu ◽  
H. Chen ◽  
W. Zheng

Background:Neutrophil-released neutrophil extracellular traps (NETs) are upregulated and promote autoinflammation and thrombosis in Behçet’s disease (BD), a multi-system inflammatory disease with unknown etiology1,2. However, whether NETs promote macrophage activation in BD remains unclear.Objectives:To investigate the potential role of NETs in promoting aberrant macrophage activation in BD.Methods:We quantified NETs by measuring dsDNA using ELISA and immunofluorescence. Macrophages were stimulated with BD- and healthy controls (HC)-derived NETs, and IL-8 and TNF-α production were measured by ELISA. NETs-stimulated macrophages were incubated with naive CD4+T cells, and Th1 cell differentiation was examined on day 7 by flow cytometry. Histones H1, H2A, H2B, H3, H4, S100A8 and neutrophil elastase in NETs were analyzed by western blot. Macrophages were stimulated with anti-Histone 4 antibody-treated NETs, and IL-8 production was measured by ELISA.Results:Circulating NETs (2336±534 ng/ml vs. 1472±549 ng/ml,P=0.0008) and neutrophil-derived NETs (909.2±485.2 ng/ml vs. 582.4±199.2 ng/ml,P=0.0108) were significantly higher in BD patients compared with those in HC. BD NETs stimulated macrophages to produce a higher level of IL-8 (17±4 ng/ml vs. 13±4 ng/ml,P=0.0474) and TNF-α (166±61 pg/ml vs. 102±48 pg/ml,P=0.0132) than HC NETs. Moreover, BD NETs promoted macrophages to facilitate Th1 differentiation than HC NETs (33±10% vs. 24±7%,P=0.0398). Western blot analysis revealed more Histone H4 (289076 (144365, 544038) IOD values vs. 42121 (6958, 129625) IOD values,P=0.0286), but not Histones H1, H2A, H2B, H3, S100A8 or neutrophil elastase in BD NETs compared to HC NETs. Importantly, neutralizing Histone H4 abrogated the BD NETs-stimulated IL-8 overproduction by macrophages (9.99±2.07 ng/ml vs. 13.95±2.91 ng/ml,P=0.021).Conclusion:BD NETs promoted macrophages activation, which might be mediated by a higher level of Histone H4.References:[1]Safi R., Kallas R., Bardawil T., et al. Neutrophils contribute to vasculitis by increased release of neutrophil extracellular traps in Behçet’s disease. J. Dermatol. Sci. 2018;92:143–150.[2]Le Joncour a, Martos r, Loyau s, et al. Critical role of neutrophil extracellular traps (NETs) in patients with Behcet’s disease. Ann Rheum Dis 2019;78:1274–1282.Disclosure of Interests:None declared

2021 ◽  
Vol 11 ◽  
Author(s):  
Lu Li ◽  
Xin Yu ◽  
Jinjing Liu ◽  
Zhimian Wang ◽  
Chaoran Li ◽  
...  

Neutrophil extracellular traps (NETs) are upregulated and promote thrombosis in Behçet’s disease (BD). However, whether NETs promote autoinflammation in BD remains unclear. This study aimed to investigate the potential role of NETs in promoting macrophage activation in BD. Firstly, we quantified NETs by measuring double-stranded DNA (dsDNA) using PicoGreen and calculating the proportion of NETosis. Then macrophages were stimulated with BD- or healthy controls (HC)-derived NETs, and IL-8 and TNF-α production and IFN-γ+ CD4+ T cells differentiation were measured using ELISA and flow cytometry, respectively. The protein components in NETs were analyzed by western blot. Macrophages were stimulated with Histone H4 neutralized NETs, and IL-8 and TNF-α production were measured using ELISA. The level of 8-hydroxydeoxyguanosine (8-OHdG) DNA in NETs was measured using ELISA. The levels of reactive oxygen species (ROS) in serum and neutrophils were measured using ROS probes by a microplate reader and flow cytometry. We found that circulating NETs and neutrophil-derived NETs were significantly higher in BD than HC. BD NETs stimulated macrophages produced higher levels of IL-8 and TNF-α, and promoted IFN-γ+ CD4+ T cells differentiation. BD NETs were enriched in Histone H4, and neutralizing Histone H4 abrogated the BD NETs-mediated IL-8 production by macrophages, but not TNF-α. Also, BD neutrophils produced more 8-OHdG DNA than HC neutrophils, and the percentage of 8-OHdG DNA in dsDNA from BD neutrophils was also higher than that of HC neutrophils. The ROS levels in serum and neutrophils were both higher in BD than HC. Our findings suggested that excessive BD NETs promoted macrophages activation and facilitated IFN-γ+ CD4+ T cells differentiation. Higher levels of Histone H4 and oxidized DNA in BD NETs might mediate macrophages hyperactivation.


2019 ◽  
Vol 78 (9) ◽  
pp. 1274-1282 ◽  
Author(s):  
Alexandre Le Joncour ◽  
Raphael Martos ◽  
Stephane Loyau ◽  
Nicolas Lelay ◽  
Antoine Dossier ◽  
...  

ObjectivesBehçet’s disease (BD) is a chronic systemic vasculitis. Thrombosis is a frequent and life-threatening complication. The pathogenesis of BD is poorly understood and evidence supporting a role for primed neutrophils in BD-associated thrombotic risk is scant. To respond to inflammatory insults, neutrophils release web-like structures, known as neutrophil extracellular traps (NETs), which are prothrombotic. We evaluated the role of NETs and markers of NETs in BD.MethodsBlood samples were collected from patients with BD, according to the International Study Group Criteria for Behçet's disease, and healthy donors (HD). NET components, including cell-free DNA (CfDNA) and neutrophil enzymes myeloperoxidase (MPO), were assessed in serum or in purified neutrophils from patients with BD and HD.ResultsPatients with active BD had elevated serum cfDNA levels and MPO-DNA complexes compared with patients with inactive BD and to HD. In addition, levels of cfDNA and MPO-DNA complexes were significantly higher in patients with BD with vascular involvement compared with those without vascular symptoms. Purified neutrophils from patients with BD exhibited spontaneous NETosis compared with HD. Thrombin generation in BD plasma was significantly increased and positively correlated with the levels of MPO-DNA complexes and cfDNA. Importantly, DNAse treatment significantly decreased thrombin generation in BD plasma but not in HD plasma. In addition, biopsy materials obtained from patients with BD showed NETs production in areas of vasculitic inflammation and thrombosis.ConclusionsOur data show that NETs and markers of NETS levels are elevated in patients with BD and contribute to the procoagulant state. Targeting NETs may represent a potential therapeutic target for the reduction or prevention of BD-associated thrombotic risk.


2013 ◽  
Vol 190 (11) ◽  
pp. 5799-5808 ◽  
Author(s):  
Sunao Sugita ◽  
Yuko Kawazoe ◽  
Ayano Imai ◽  
Tatsushi Kawaguchi ◽  
Shintaro Horie ◽  
...  

2018 ◽  
Vol 92 (2) ◽  
pp. 143-150 ◽  
Author(s):  
Rémi Safi ◽  
Romy Kallas ◽  
Tara Bardawil ◽  
Carl Joe Mehanna ◽  
Ossama Abbas ◽  
...  

2021 ◽  
pp. 1-10
Author(s):  
Asmaa Kamal ◽  
Fatema T Elgengehy ◽  
Zahraa Elawady ◽  
Nahla A. Fawzy ◽  
Ola El Sisi

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 1562.1-1563
Author(s):  
L. Sun ◽  
J. Liu ◽  
W. Zheng

Background:Vascular involvement is one of the leading causes of mortality and morbidity in Behcet’s Disease (BD)1. Surgical treatments are difficult for Vaculo-BD (VBD) patients due to the high risk of serious postoperative complications without effective and promptly perioperative immunotherapy2, 3. Anti-tumor necrosis factor alpha (TNF-α) therapy has been reported as a potential treatment in severe VBD, e.g. infliximab (IFX) and adalimumab (ADA). However, only few case reports are available regarding the fully humanized monoclonal antibody to TNF-α, golimumab (GOL), in the management of VBD4.Objectives:The objective of this study was to report the efficacy and safety of GOL for the treatment of severe and/or refractory VBD.Methods:We retrospectively analyzed the efficacy and safety profile of patients with severe and/or refractory VBD treated with GOL in our medical center between 2018 to 2020.Results:Nine VBD patients (8 male and 1 female) were enrolled, with a mean age and median course of 37±8.6 years and 72 months (range 12 to 300), respectively. Cardiac involvements (severe aortic regurgitation secondary to BD) were presented in 7 patients, including 2 patients with post-operative paravalvular leakage (PVL) after aortic valve replacement surgery. Multiple vascular lesions were documented in the other 2 patients, including one patient with life-threatening multiple pulmonary aneurysms, pulmonary thromboembolism and recurrent deep vein thrombosis, and another patient with abdominal aortic pseudoaneurysm and multiple artery stenosis and occlusion. Prior to GOL therapy, all patients experienced disease progression despite high-dose glucocorticoids combined with multiple immunosuppressants. Moreover, seven patients required effective and fast control of inflammation and a decrease of glucocorticoid dose during the perioperative period. They were treated with GOL, 50mg every 4 weeks, in combination with background low-or medium-dose glucocorticoids and immunosuppressants, for a median of 6 (range 3-15) months. After a mean duration of follow-up of 10 (range 2-6) months, all patients achieved improvement both in clinical symptoms and serum inflammation markers. The ESR level [4.88±4.94 mm/h vs 31.13±31.78mm/h, P<0.01] and CRP level [1.9 (0.11-3.73)mg/L vs 24.3 (0.4-85.57)mg/L, P<0.01] significantly decreased. The dosage of glucocorticoid[10 (0-15) vs 40 (0-100)mg/d, P<0.01] effectively tapered, indicating a potential steroid-sparing effect. No newly-onset aneurysm and recurrent venous thrombosis were observed. Also, one patient had a marked reduction in size and number of pulmonary aneurysms. No post-operative PVL was observed in the five patients after Bentall operation with a median follow-up of 10 months. One patient with severe aortic regurgitation remained stable and without surgical intervention with the treatment of GOL for 16 months. No severe complication occurred in one patient after underwent endovascular repair of abdominal aorta for 8 months. GOL was well-tolerated, and no serious adverse event was observed.Conclusion:Our results suggested that GOL is safe and effective for the treatment of patients with severe and / or refractory VBD. Further controlled studies are warranted to confirm the therapeutic potential of GOL in VBD patients.Disclosure of Interests:None declared


2021 ◽  
Vol 16 (S1) ◽  
Author(s):  
Isabelle Kone-Paut ◽  
◽  
Stéphane Barete ◽  
Bahram Bodaghi ◽  
Kumaran Deiva ◽  
...  

AbstractBehçet’s disease (BD) is a systemic variable vessel vasculitis that involves the skin, mucosa, joints, eyes, arteries, veins, nervous system and gastrointestinal system, presenting with remissions and exacerbations. It is a multifactorial disease, and several triggering factors including oral cavity infections and viruses may induce inflammatory attacks in genetically susceptible individuals. BD vasculitis involves different vessel types and sizes of the vascular tree with mixed-cellular perivascular infiltrates and is often complicated by recurrent thrombosis, particularly in the venous compartment. Several new therapeutic modalities with different mechanisms of action have been studied in patients with BD. A substantial amount of new data have been published on the management of BD, especially with biologics, over the last years. These important therapeutic advances in BD have led us to propose French recommendations for the management of Behçet’s disease [Protocole National de Diagnostic et de Soins de la maladie de Behçet (PNDS)]. These recommendations are divided into two parts: (1) the diagnostic process and initial assessment; (2) the therapeutic management. Thirty key points summarize the essence of the recommendations. We highlighted the main differential diagnosis of BD according to the type of clinical involvement; the role of genetics is also discussed, and we indicate the clinical presentations that must lead to the search for a genetic cause.


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