Visualization of neutrophil extracellular traps and fibrin meshwork in Human fibrinopurulent inflammatory lesions: II. Ultrastructural study

Takanori Onouchi, Kazuya Shiogama, Takahiro Matsui, Yasuyoshi Mizutani, Kouhei Sakurai, Ken Ichi Inada, Yutaka Tsutsumi

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11 Citations (Scopus)


Neutrophil extracellular traps (NETs) represent an extracellular, spider’s web-like structure resulting from cell death of neutrophils. NETs play an important role in innate immunity against microbial infection, but their roles in human pathological processes remain largely unknown. NETs and fibrin meshwork both showing fibrillar structures are observed at the site of fibrinopurulent inflammation, as described in our sister paper [Acta Histochem. Cytochem. 49; 109-116, 2016]. In the present study, immunoelectron microscopic study was performed for visualizing NETs and fibrin fibrils (thick fibrils in our tongue) in formalin-fixed, paraffin-embedded sections of autopsied lung tissue of legionnaire’s pneumonia. Lactoferrin and fibrinogen gamma chain were utilized as markers of NETs and fibrin, respectively. Analysis of immuno-scanning electron microscopy indicated that NETs constructed thin fibrils and granular materials were attached onto the NETs fibrils. The smooth-surfaced fibrin fibrils were much thicker than the NETs fibrils. Pre-embedding immunoelectron microscopy demonstrated that lactoferrin immunoreactivities were visible as dots on the fibrils, whereas fibrinogen gamma chain immunoreactivities were homogeneously observed throughout the fibrils. Usefulness of immunoelectron microscopic analysis of NETs and fibrin fibrils should be emphasized.

Original languageEnglish
Pages (from-to)117-123
Number of pages7
JournalActa Histochemica et Cytochemica
Issue number4
Publication statusPublished - 01-01-2016


All Science Journal Classification (ASJC) codes

  • Pathology and Forensic Medicine
  • Biochemistry
  • Physiology
  • Histology
  • Cell Biology

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