Department of Cellular Microbiology, Max Planck Institute for Infection Biology, Berlin, Germany
Alf Herzig
Department of Cellular Microbiology, Max Planck Institute for Infection Biology, Berlin, Germany
Renate Krüger
Department of Paediatric Pneumology and Immunology, Outpatient Clinic for Primary Immunodeficiencies, Charité Medical School, Berlin, Germany; Sozialpädiatrisches Zentrum, Charité Medical School, Berlin, Germany
Department of Biochemistry and Pharmacology, University of Massachusetts Medical School, Worcester, United States
Santanu Mondal
Department of Biochemistry and Pharmacology, University of Massachusetts Medical School, Worcester, United States
Paul R Thompson
Department of Biochemistry and Pharmacology, University of Massachusetts Medical School, Worcester, United States
Volker Brinkmann
Microscopy Core Facility, Max Planck Institute for Infection Biology, Berlin, Germany
Horst von Bernuth
Department of Paediatric Pneumology and Immunology, Outpatient Clinic for Primary Immunodeficiencies, Charité Medical School, Berlin, Germany; Sozialpädiatrisches Zentrum, Charité Medical School, Berlin, Germany; Labor Berlin, Section for Immunology, Charité–Vivantes GmbH, Berlin, Germany; Berlin Centre for Regenerative Therapies, Charité Medical School, Berlin, Germany
Arturo Zychlinsky
Department of Cellular Microbiology, Max Planck Institute for Infection Biology, Berlin, Germany
Neutrophils release neutrophil extracellular traps (NETs) which ensnare pathogens and have pathogenic functions in diverse diseases. We examined the NETosis pathways induced by five stimuli; PMA, the calcium ionophore A23187, nigericin, Candida albicans and Group B Streptococcus. We studied NET production in neutrophils from healthy donors with inhibitors of molecules crucial to PMA-induced NETs including protein kinase C, calcium, reactive oxygen species, the enzymes myeloperoxidase (MPO) and neutrophil elastase. Additionally, neutrophils from chronic granulomatous disease patients, carrying mutations in the NADPH oxidase complex or a MPO-deficient patient were examined. We show that PMA, C. albicans and GBS use a related pathway for NET induction, whereas ionophores require an alternative pathway but that NETs produced by all stimuli are proteolytically active, kill bacteria and composed mainly of chromosomal DNA. Thus, we demonstrate that NETosis occurs through several signalling mechanisms, suggesting that extrusion of NETs is important in host defence.
