IL-1β dominates the promucin secretory cytokine profile in cystic fibrosis

J Clin Invest. 2019 Oct 1;129(10):4433-4450. doi: 10.1172/JCI125669.

Abstract

Cystic fibrosis (CF) lung disease is characterized by early and persistent mucus accumulation and neutrophilic inflammation in the distal airways. Identification of the factors in CF mucopurulent secretions that perpetuate CF mucoinflammation may provide strategies for novel CF pharmacotherapies. We show that IL-1β, with IL-1α, dominated the mucin prosecretory activities of supernatants of airway mucopurulent secretions (SAMS). Like SAMS, IL-1β alone induced MUC5B and MUC5AC protein secretion and mucus hyperconcentration in CF human bronchial epithelial (HBE) cells. Mechanistically, IL-1β induced the sterile α motif-pointed domain containing ETS transcription factor (SPDEF) and downstream endoplasmic reticulum to nucleus signaling 2 (ERN2) to upregulate mucin gene expression. Increased mRNA levels of IL1B, SPDEF, and ERN2 were associated with increased MUC5B and MUC5AC expression in the distal airways of excised CF lungs. Administration of an IL-1 receptor antagonist (IL-1Ra) blocked SAMS-induced expression of mucins and proinflammatory mediators in CF HBE cells. In conclusion, IL-1α and IL-1β are upstream components of a signaling pathway, including IL-1R1 and downstream SPDEF and ERN2, that generate a positive feedback cycle capable of producing persistent mucus hyperconcentration and IL-1α and/or IL-1β-mediated neutrophilic inflammation in the absence of infection in CF airways. Targeting this pathway therapeutically may ameliorate mucus obstruction and inflammation-induced structural damage in young CF children.

Keywords: Cytokines; Pulmonology.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Case-Control Studies
  • Cells, Cultured
  • Cystic Fibrosis / genetics
  • Cystic Fibrosis / metabolism*
  • Cystic Fibrosis / pathology
  • Female
  • Gene Expression Regulation
  • Humans
  • Interleukin-1alpha / genetics
  • Interleukin-1alpha / metabolism
  • Interleukin-1beta / genetics
  • Interleukin-1beta / metabolism*
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Mucin 5AC / genetics
  • Mucin 5AC / metabolism
  • Mucin-5B / genetics
  • Mucin-5B / metabolism
  • Mucus / metabolism*
  • Protein Serine-Threonine Kinases / genetics
  • Protein Serine-Threonine Kinases / metabolism
  • Proto-Oncogene Proteins c-ets / deficiency
  • Proto-Oncogene Proteins c-ets / genetics
  • Proto-Oncogene Proteins c-ets / metabolism
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Receptors, Interleukin-1 Type I / deficiency
  • Receptors, Interleukin-1 Type I / genetics
  • Receptors, Interleukin-1 Type I / metabolism
  • Respiratory Mucosa / metabolism
  • Respiratory Mucosa / pathology
  • Signal Transduction

Substances

  • IL1A protein, human
  • IL1B protein, human
  • IL1R1 protein, mouse
  • Interleukin-1alpha
  • Interleukin-1beta
  • Membrane Proteins
  • Mucin 5AC
  • Mucin-5B
  • Proto-Oncogene Proteins c-ets
  • RNA, Messenger
  • Receptors, Interleukin-1 Type I
  • Spdef protein, mouse
  • Ern2 protein, mouse
  • Protein Serine-Threonine Kinases