title: Cigarette smoke-induced necroptosis and DAMP release trigger neutrophilic airway inflammation in mice.
abstract: Recent data indicate a role for airway epithelial necroptosis, a regulated form of necrosis, and the associated release of damage-associated molecular patterns (DAMPs) in the development of chronic obstructive pulmonary disease (COPD). DAMPs can activate pattern recognition receptors (PRRs), triggering innate immune responses. We hypothesized that cigarette smoke (CS)-induced epithelial necroptosis and DAMP release initiate airway inflammation in COPD. Human bronchial epithelial BEAS-2B cells were exposed to cigarette smoke extract (CSE), and necrotic cell death (membrane integrity by propidium iodide staining) and DAMP release (i.e., double-stranded DNA, high-mobility group box 1, heat shock protein 70, mitochondrial DNA, ATP) were analyzed. Subsequently, BEAS-2B cells were exposed to DAMP-containing supernatant of CS-induced necrotic cells, and the release of proinflammatory mediators [C-X-C motif ligand 8 (CXCL-8), IL-6] was evaluated. Furthermore, mice were exposed to CS in the presence and absence of the necroptosis inhibitor necrostatin-1, and levels of DAMPs and inflammatory cell numbers were determined in bronchoalveolar lavage fluid. CSE induced a significant increase in the percentage of necrotic cells and DAMP release in BEAS-2B cells. Stimulation of BEAS-2B cells with supernatant of CS-induced necrotic cells induced a significant increase in the release of CXCL8 and IL-6, in a myeloid differentiation primary response gene 88-dependent fashion. In mice, exposure of CS increased the levels of DAMPs and numbers of neutrophils in bronchoalveolar lavage fluid, which was statistically reduced upon treatment with necrostatin-1. Together, we showed that CS exposure induces necrosis of bronchial epithelial cells and subsequent DAMP release in vitro, inducing the production of proinflammatory cytokines. In vivo, CS exposure induces neutrophilic airway inflammation that is sensitive to necroptosis inhibition.
authors.affiliation: Department of Pathology and Medical Biology, Experimental Pulmonology and Inflammation Research, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands; GRIAC Research Institute, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands;
authors.forename: Simon D
authors.initials: SD
authors.lastname: Pouwels
authors.affiliation: Department of Pathology and Medical Biology, Experimental Pulmonology and Inflammation Research, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands; GRIAC Research Institute, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands; Department of Pulmonology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands;
authors.forename: G Jan
authors.initials: GJ
authors.lastname: Zijlstra
authors.affiliation: Department of Pathology and Medical Biology, Experimental Pulmonology and Inflammation Research, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands; GRIAC Research Institute, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands;
authors.forename: Marco
authors.initials: M
authors.lastname: van der Toorn
authors.affiliation: Department of Pathology and Medical Biology, Experimental Pulmonology and Inflammation Research, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands; GRIAC Research Institute, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands;
authors.forename: Laura
authors.initials: L
authors.lastname: Hesse
authors.affiliation: Department of Pathology and Medical Biology, Experimental Pulmonology and Inflammation Research, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands; GRIAC Research Institute, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands;
authors.forename: Renee
authors.initials: R
authors.lastname: Gras
authors.affiliation: GRIAC Research Institute, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands; Department of Pulmonology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands;
authors.forename: Nick H T
authors.initials: NH
authors.lastname: Ten Hacken
authors.affiliation: Molecular Signaling and Cell Death Unit, Inflammation Research Center, VIB, Ghent, Belgium; and Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium.
authors.forename: Dmitri V
authors.initials: DV
authors.lastname: Krysko
authors.affiliation: Molecular Signaling and Cell Death Unit, Inflammation Research Center, VIB, Ghent, Belgium; and Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium.
authors.forename: Peter
authors.initials: P
authors.lastname: Vandenabeele
authors.affiliation: Department of Pathology and Medical Biology, Experimental Pulmonology and Inflammation Research, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands; GRIAC Research Institute, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands;
authors.forename: Maaike
authors.initials: M
authors.lastname: de Vries
authors.affiliation: Department of Pathology and Medical Biology, Experimental Pulmonology and Inflammation Research, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands; GRIAC Research Institute, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands;
authors.forename: Antoon J M
authors.initials: AJ
authors.lastname: van Oosterhout
authors.affiliation: Department of Pathology and Medical Biology, Experimental Pulmonology and Inflammation Research, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands; GRIAC Research Institute, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands;
authors.forename: Irene H
authors.initials: IH
authors.lastname: Heijink
authors.affiliation: Department of Pathology and Medical Biology, Experimental Pulmonology and Inflammation Research, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands; GRIAC Research Institute, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands; m.c.nawijn@umcg.nl.
authors.forename: Martijn C
authors.initials: MC
authors.lastname: Nawijn
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D004847:Epithelial Cells / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D007249:Inflammation / Q000378:metabolism; D008168:Lung / Q000378:metabolism*; D051379:Mice; D009336:Necrosis / Q000139:chemically induced; D009504:Neutrophils / Q000378:metabolism*; D029424:Pulmonary Disease, Chronic Obstructive / Q000209:etiology / Q000378:metabolism; D012906:Smoke / Q000009:adverse effects*; D012907:Smoking / Q000009:adverse effects / Q000378:metabolism; D014026:Nicotiana / Q000009:adverse effects*
chemical_list: D012906:Smoke
keywords: airway epithelium; chronic obstructive pulmonary disease; cigarette smoke; damage-associated molecular patterns; necroptosis