1 research outputs found
Supplementary Material for: Neutrophil Extracellular Traps Stimulate Proinflammatory Responses in Human Airway Epithelial Cells
<p>Tissue injury leads to the release of uric acid (UA). At high local
concentrations, UA can form monosodium urate crystals (MSU). MSU and UA
stimulate neutrophils to release extracellular traps (NET). Here, we
investigated whether these NET could be involved in the development of
inflammation by stimulating cytokine release by airway epithelial cells.
We found that NET significantly increased the secretion of CXCL8/IL-8
and IL-6 by alveolar and bronchial epithelial cells. These effects were
not observed when NETosis was inhibited by Diphenyleneiodonium, elastase
inhibitor, or Cl-amidine. Similar findings were made with NET induced
by cigarette smoke extract, suggesting that NET proinflammatory capacity
is independent of the inducing stimulus. Furthermore, NET affected
neither the viability and morphology of epithelial cells nor the barrier
integrity of polarized cells. The epithelial stimulatory capacity of
NET was not affected by degradation of DNA with micrococcal nuclease,
treatment with heparin, or inhibition of the elastase immobilized to
DNA, but it was significantly reduced by pretreatment with an
anti-HMGB-1 blocking antibody. Altogether, our findings indicate that
NET exert direct proinflammatory effects on airway epithelial cells that
might contribute in vivo to the further recruitment of neutrophils and
the perpetuation of inflammation upon lung tissue damage.</p