NETosis proceeds by cytoskeleton and endomembrane disassembly and PAD4-mediated chromatin decondensation and nuclear envelope rupture

Hawa Racine Thiama, Siu Ling Wong, Rong Qiu, Mark Kittisopikul, Amir Vahabikashi, Anne E. Goldman, Robert D. Goldman, Denisa D. Wagner, Clare M. Waterman*

*Corresponding author for this work

Research output: Contribution to journalArticle

1 Scopus citations

Abstract

Neutrophil extracellular traps (NETs) are web-like DNA structures decorated with histones and cytotoxic proteins that are released by activated neutrophils to trap and neutralize pathogens during the innate immune response, but also form in and exacerbate sterile inflammation. Peptidylarginine deiminase 4 (PAD4) citrullinates histones and is required for NET formation (NETosis) in mouse neutrophils. While the in vivo impact of NETs is accumulating, the cellular events driving NETosis and the role of PAD4 in these events are unclear. We performed high-resolution time-lapse microscopy of mouse and human neutrophils and differentiated HL-60 neutrophil-like cells (dHL-60) labeled with fluorescent markers of organelles and stimulated with bacterial toxins or Candida albicans to induce NETosis. Upon stimulation, cells exhibited rapid disassembly of the actin cytoskeleton, followed by shedding of plasma membrane microvesicles, disassembly and remodeling of the microtubule and vimentin cytoskeletons, ER vesiculation, chromatin decondensation and nuclear rounding, progressive plasma membrane and nuclear envelope (NE) permeabilization, nuclear lamin meshwork and then NE rupture to release DNA into the cytoplasm, and finally plasma membrane rupture and discharge of extracellular DNA. Inhibition of actin disassembly blocked NET release. Mouse and dHL-60 cells bearing genetic alteration of PAD4 showed that chromatin decondensation, lamin meshwork and NE rupture and extracellular DNA release required the enzymatic and nuclear localization activities of PAD4. Thus, NETosis proceeds by a stepwise sequence of cellular events culminating in the PAD4- mediated expulsion of DNA.

Original languageEnglish (US)
Pages (from-to)7326-7337
Number of pages12
JournalProceedings of the National Academy of Sciences of the United States of America
Volume117
Issue number13
DOIs
StatePublished - Mar 31 2020

Keywords

  • Innate immunity
  • Microscopy
  • Neutrophil

ASJC Scopus subject areas

  • General

Fingerprint Dive into the research topics of 'NETosis proceeds by cytoskeleton and endomembrane disassembly and PAD4-mediated chromatin decondensation and nuclear envelope rupture'. Together they form a unique fingerprint.

  • Cite this