A Selective α7 Nicotinic Acetylcholine Receptor Agonist, PNU-282987, Attenuates ILC2s Activation and Alternaria-Induced Airway Inflammation

Front Immunol. 2021 Feb 1:11:598165. doi: 10.3389/fimmu.2020.598165. eCollection 2020.

Abstract

Background: The anti-inflammatory effect of an α7nAChR agonist, PNU-282987, has previously been explored in the context of inflammatory disease. However, the effects of PNU-282987 on type 2 innate lymphoid cells (ILC2s)-mediated allergic airway inflammation has not yet been established.

Aims: To determine the effects of PNU-282987 on the function of ILC2s in the context of IL-33- or Alternaria Alternata (AA)- induced airway inflammation.

Methods: PNU-282987 was administered to mice that received recombinant IL-33 or AA intranasal challenges. Lung histological analysis and flow cytometry were performed to determine airway inflammation and the infiltration and activation of ILC2s. The previously published α7nAChR agonist GTS-21 was employed as a comparable reagent. ILC2s were isolated from murine lung tissue and cultured in vitro in the presence of IL-33, IL-2, and IL-7 with/without either PNU-282987 or GTS-21. The expression of the transcription factors GATA3, IKK, and NF-κB were also determined.

Results: PNU-282987 and GTS-21 significantly reduced goblet cell hyperplasia in the airway, eosinophil infiltration, and ILC2s numbers in BALF, following IL-33 or AA challenge. In vitro IL-33 stimulation of isolated lung ILC2s showed a reduction of GATA3 and Ki67 in response to PNU-282987 or GTS-21 treatments. There was a significant reduction in IKK and NF-κB phosphorylation in the PNU-282987-treated group when compared to the GTS-21-treated ILC2s.

Conclusion: PNU-282987 inhibits ILC2-associated airway inflammation, where its effects were comparable to that of GTS-21.

Keywords: Alternaria; airway; inflammation; nicotinic acetylcholine receptor; type 2 innate lymphoid cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Asthma / drug therapy
  • Asthma / etiology*
  • Asthma / metabolism*
  • Asthma / pathology
  • Benzamides / pharmacology*
  • Benzylidene Compounds / pharmacology
  • Biomarkers
  • Bridged Bicyclo Compounds / pharmacology*
  • Cytokines / metabolism
  • Disease Models, Animal
  • Female
  • Immunity, Innate / drug effects*
  • Immunohistochemistry
  • Immunophenotyping
  • Interleukin-33 / metabolism
  • Lymphocytes / drug effects*
  • Lymphocytes / physiology*
  • Mice
  • Nicotinic Agonists / pharmacology*
  • Pyridines / pharmacology
  • alpha7 Nicotinic Acetylcholine Receptor / agonists*

Substances

  • Benzamides
  • Benzylidene Compounds
  • Biomarkers
  • Bridged Bicyclo Compounds
  • Cytokines
  • Interleukin-33
  • Nicotinic Agonists
  • PNU-282987
  • Pyridines
  • alpha7 Nicotinic Acetylcholine Receptor
  • 3-(2,4-dimethoxybenzylidene)anabaseine