Eosinophil extracellular traps activate type 2 innate lymphoid cells through stimulating airway epithelium in severe asthma

Background Activated eosinophils release extracellular traps (EETs), which contribute to airway inflammation in severe asthma (SA). However, the role of EETs in innate immunity has not yet been completely determined. The present study aimed to demonstrate the mechanism of airway inflammation in SA mediated by EETs. Methods Peripheral counts of EET+ eosinophils and type 2 innate lymphoid cells (ILC2s) were evaluated in patients with SA (n = 13), nonsevere asthma (NSA, n = 17), and healthy control subjects (HC, n = 8). To confirm the effect of EETs, airway hyperresponsiveness (AHR) and adapted/innate immune responses were assessed in mice. Furthermore, the effects of anti‐IL‐33/TSLP antibody were tested. Results The numbers of EET+ eosinophils and ILC2s were significantly elevated in SA, with a positive correlation between these two cells (r = .539, P