Oxidative Burst-Dependent NETosis Is Implicated in the Resolution of Necrosis-Associated Sterile Inflammation.
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ABSTRACT:
SUBMITTER: Biermann MH
PROVIDER: S-EPMC5131011 | biostudies-literature | 2016
REPOSITORIES: biostudies-literature
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Oxidative Burst-Dependent NETosis Is Implicated in the Resolution of Necrosis-Associated Sterile Inflammation.
Biermann Mona H C MH Podolska Malgorzata J MJ Knopf Jasmin J Reinwald Christiane C Weidner Daniela D Maueröder Christian C Hahn Jonas J Kienhöfer Deborah D Barras Alexandre A Boukherroub Rabah R Szunerits Sabine S Bilyy Rostyslav R Hoffmann Markus M Zhao Yi Y Schett Georg G Herrmann Martin M Munoz Luis E LE
Frontiers in immunology 20161201
Necrosis is associated with a profound inflammatory response. The regulation of necrosis-associated inflammation, particularly the mechanisms responsible for resolution of inflammation is incompletely characterized. Nanoparticles are known to induce plasma membrane damage and necrosis followed by sterile inflammation. We observed that injection of metabolically inert nanodiamonds resulted in paw edema in WT and <i>Ncf1**</i> mice. However, while inflammation quickly resolved in WT mice, it persi ...[more]
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Project description:Loss-of-function (LOF) mutations in NFKB1, coding for p105, may cause common variable immunodeficiency due to dysregulation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κΒ) pathway. Monoallelic LOF variants of NFKB1 can predispose to uncontrolled inflammation including sterile necrotizing fasciitis or pyoderma gangrenosum. In this study, we explored the impact of a heterozygous NFKB1 c.C936T/p.R157X LOF variant on immunity in sterile fasciitis patients and their family members. The p50 or p105 protein levels were reduced in all variant carriers. Interleukin-1β (IL-1β) and interleukin-8 (IL-8) levels were elevated in vitro, potentially contributing to the very high neutrophil counts observed during fasciitis episodes. Phosphorylation of p65/RelA was reduced in p.R157X neutrophils suggesting defective activation of canonical NF-κB. Oxidative burst after NF-κB-independent phorbol 12-myristate 13-acetate (PMA) stimulation was similar in both p.R157X and control neutrophils. Comparable amounts of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex subunits were found in p.R157X and control neutrophils. However, a compromised oxidative burst was observed in p.R157X neutrophils following activation of NF-κB-dependent mechanisms following stimulation of toll-like receptor 2 (TLR2) and Dectin-1. Neutrophil extracellular trap formation was not affected by p.R157X. In summary, the NFKB1 c.C936T/p.R157X LOF variant has an impact on inflammation and neutrophil function and may play a role in the pathogenesis of sterile necrotizing fasciitis.
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Project description:ImportanceRandomized clinical trials are conducted to establish both drug safety and efficacy. However, evidence of adverse events associated with these drugs in the clinical practice setting can be of value at generating hypotheses regarding less common safety issues, even if causality cannot be determined.ObjectiveTo present and analyze cases of intraocular inflammation associated with faricimab therapy in patients referred to a single European institution.Design, setting, and participantsThis was a review starting in April of 2024 of an observational case series. Patients were from a single academic-based tertiary referral center in Switzerland. Included in the analysis were patients referred for intraocular inflammation soon after receiving a faricimab intravitreal injection between June 1, 2022, and March 5, 2024.ExposureFaricimab, 6 mg (0.05 mL of a 120-mg/mL solution), administrated for neovascular age-related macular degeneration or diabetic macular edema.Main outcomes and measuresThe systemic and ocular histories and imaging data available were reviewed. The following were evaluated: visual acuity measured with habitual correction using the Early Treatment of Diabetic Retinopathy Study charts before and after the event; intraocular pressure; patient symptoms; anterior, intermediate, or posterior location of the intraocular inflammation; and the presence of retinal vasculitis. Multimodal imaging including color fundus photographs, fluorescein angiograms, indocyanine green angiograms, and optical coherence tomography were reviewed.ResultsA total of 12 eyes from 7 patients (mean [SD] age, 73.3 [16.7] years; 4 female [57.1%]) over 22 months were identified as having noninfectious intraocular inflammation after intravitreal faricimab injections. Among these cases, in 2 eyes, retinal vasculitis was present together with anterior and posterior inflammation. One of the 2 eyes had an occlusive form of vasculitis of the arteries and veins, leading to subsequent macular capillary nonperfusion and clinically relevant irreversible vision deterioration from 20/80 to 20/2000. The remaining eyes were characterized by moderate anterior segment inflammation without substantial vision changes. The intraocular inflammation event occurred after a median (IQR) of 3.5 (2.0-4.3) faricimab injections. The median (IQR) interval between the last faricimab injection and the diagnosis of inflammation was 28 (24-38) days. Increased intraocular pressure of 30 mm Hg or higher was found in 3 eyes.Conclusions and relevanceThis case series highlights the occurrence of rare, but potentially severe, intraocular inflammation associated with faricimab therapy. Although these findings do not prove causality and can only generate hypotheses for future investigations, these results suggest the importance of continuous surveillance and monitoring for patients undergoing faricimab therapy to promptly identify and manage potential adverse events.
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