Neutrophil extracellular traps involved in the pathogenesis of IgA vasculitis: Confirmed in two IgAV rat models

PLoS One. 2023 Jul 21;18(7):e0288538. doi: 10.1371/journal.pone.0288538. eCollection 2023.

Abstract

Background: Neutrophil extracellular traps (NETs) have been found to play a role in the development of autoimmune diseases. In the past two years, studies have demonstrated a significantly increase of NETs in skin tissues during the early stages of IgAV, indicating their involvement in disease activity among children with IgAV. However, the presence of NETs in IgAV animal models has not yet been reported. The objective of this study is to investigate whether NETs are involved in the pathogenesis of IgA vasculitis (IgAV) rats.

Methods: Twenty-four SD rats were randomly divided into three groups: the ovalbumin group, the gliadin group, and the control group. The IgAV rat models were established administering Indian ink with ovalbumin (ovalbumin group) or gliadin (gliadin group) with Freund's complete adjuvant. The cell-free DNA (cf-DNA) was quantified by using dsDNA quantification kit, while the levels of Immunoglobulins, complement C3 and myeloperoxidase-DNA (MPO-DNA) in serum were tested using enzyme linked immunosorbent assay (ELISA). The IgA, complement C3 and NETs in tissues were detected through multiple immunofluorescences.

Results: Both the ovalbumin group and gliadin group showed IgA and C3 deposition in various tissues, including the glomerular mesangial region, skin, and digestive tract, while the control group showed no such deposition. The levels of circulatory cf-DNA and MPO-DNA, which are components of NETs, were significantly elevated in both ovalbumin and gliadin groups compared with the control group. Furthermore, the presence of NETs were found in gastrointestinal and renal tissues of the ovalbumin and gliadin groups, but not in the control group.

Conclusions: IgAV model rat can be established through the combination of ovalbumin and gliadin with Indian ink and Freund's complete adjuvant. This study provides the first confirmation that NETs are involved in the pathogenesis of IgAV rat.

MeSH terms

  • Animals
  • Child
  • Complement C3
  • DNA
  • Extracellular Traps*
  • Gliadin
  • Humans
  • IgA Vasculitis*
  • Immunoglobulin A
  • Ovalbumin
  • Rats
  • Rats, Sprague-Dawley

Substances

  • Complement C3
  • Ovalbumin
  • Gliadin
  • Immunoglobulin A
  • DNA

Grants and funding

This study was supported by Innovation Project of Guangxi Graduate Education (NO: YCBZ2021047); Research Basic Ability Enhancement Project of Young and Middle-aged Teachers in Guangxi Universities (NO: 2021KY0096); Excellent Medical Talents Training Program of the First Affiliated Hospital of Guangxi Medical University and Guangxi Medical High-level Backbone Talent "139" Plan (No. G201901010]) and the Key Laboratory of Children's Disease Research in Guangxi’s Colleges and Universities, Education Department of Guangxi Zhuang Autonomous Region.