title: Iron-chelating agent, deferasirox, inhibits neutrophil activation and extracellular trap formation.
abstract: Iron-chelating agents, which are frequently prescribed to transfusion-dependent patients, have various useful biological effects in addition to chelation. Reactive oxygen species (ROS) produced by neutrophils can cause pulmonary endothelial cell damage, which can lead to acute lung injury (ALI). We previously reported that deferasirox (DFS), an iron-chelating agent, inhibits phorbol myristate acetate (PMA) or formyl-methionyl-leucyl-phenylalanine (fMLP)-induced ROS production in neutrophils, in vitro. Here, we investigate whether DFS inhibits vacuolization in neutrophils and neutrophil extracellular trap (NET) formation. Human neutrophils were incubated with DFS and stimulated with PMA or fMLP. Human neutrophils were separated from heparinized peripheral blood using density gradient centrifugation, and subsequently incubated with DFS. After 10 minutes, neutrophils were stimulated by PMA or fMLP. Vacuole formation was observed by electron microscopy. For observing NET formations using microscopes, immunohistological analyses using citrullinated histone H3 and myeloperoxidase antibodies, and SYTOX Green (an impermeable DNA detection dye) staining, were conducted. NET formation was measured as the quantity of double-stranded DNA (dsDNA), using the AccuBlue Broad Range dsDNA Quantitation Kit. DFS (50 μmol/L) inhibited vacuole formation in the cytoplasm and NET formation. Additionally, 5-100 μmol/L concentration of DFS inhibited the release of dsDNA in a dose-independent manner. We demonstrate that DFS inhibits not only ROS production but also vacuolization and NET formation in neutrophils. These results suggest the possibility of protective effects of DFS against NET-related adverse effects, including ALI and thrombosis.
authors.affiliation: Scientific Research, Scientific Affairs, Sysmex Corporation, Kobe, Japan.
authors.forename: Mari
authors.initials: M
authors.lastname: Kono
authors.affiliation: Faculty of Pharmacological Sciences, Himeji Dokkyo University, Himeji, Japan.
authors.forename: Katsuyasu
authors.initials: K
authors.lastname: Saigo
authors.affiliation: Scientific Research, Scientific Affairs, Sysmex Corporation, Kobe, Japan.
authors.forename: Shiori
authors.initials: S
authors.lastname: Yamamoto
authors.affiliation: Faculty of Pharmacological Sciences, Himeji Dokkyo University, Himeji, Japan.
authors.forename: Kohei
authors.initials: K
authors.lastname: Shirai
authors.affiliation: Faculty of Pharmacological Sciences, Himeji Dokkyo University, Himeji, Japan.
authors.forename: Shuta
authors.initials: S
authors.lastname: Iwamoto
authors.affiliation: Faculty of Pharmacological Sciences, Himeji Dokkyo University, Himeji, Japan.
authors.forename: Tomoko
authors.initials: T
authors.lastname: Uematsu
authors.affiliation: Department of Hematology, Shinko Hospital, Kobe, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Takahashi
authors.affiliation: Department of Health Science, Kobe Tokiwa University, Kobe, Japan.
authors.forename: Shion
authors.initials: S
authors.lastname: Imoto
authors.affiliation: Kobe University Hospital, Kobe, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Hashimoto
authors.affiliation: Kobe University Hospital, Kobe, Japan.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Minami
authors.affiliation: Scientific Research, Scientific Affairs, Sysmex Corporation, Kobe, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Wada
authors.affiliation: Faculty of Pharmacological Sciences, Himeji Dokkyo University, Himeji, Japan.
authors.forename: Mariko
authors.initials: M
authors.lastname: Takenokuchi
authors.affiliation: Kobe University Hospital, Kobe, Japan.
authors.forename: Seiji
authors.initials: S
authors.lastname: Kawano
mesh_terms: D001565:Benzoates / Q000494:pharmacology*; D002478:Cells, Cultured; D000077588:Deferasirox; D004305:Dose-Response Relationship, Drug; D065206:Extracellular Traps / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D007502:Iron Chelating Agents / Q000494:pharmacology*; D018375:Neutrophil Activation / Q000187:drug effects* / Q000502:physiology; D010587:Phagocytosis / Q000187:drug effects / Q000502:physiology; D017382:Reactive Oxygen Species / Q000378:metabolism; D014230:Triazoles / Q000494:pharmacology*
chemical_list: D001565:Benzoates; D007502:Iron Chelating Agents; D017382:Reactive Oxygen Species; D014230:Triazoles; D000077588:Deferasirox
keywords: iron chelators; morphology; neutrophils