METHODS: We compared levels of autophagy and EET production from peripheral blood eosinophils isolated from patients with SA (n=10) and NSA (n=13) by immunocytochemistry. Effects of EETs on airway epithelial cells (AECs) were evaluated in vitro.
RESULTS: Upon IL-5 and LPS stimulation, PBEs from SA patients showed high levels of autophagy (P = 0.022) and EET production (P = 0.037) compared to those from NSA patients, which were in a positive correlation (r = 0.758, P < 0.001). LY294002, a phosphoinositide 3-kinase (PI3K) inhibitor, significantly reduced both autophagy and EET production. EET could trigger immune responses of AECs by inducing interleukin (IL)-6 and IL-8 production from A549 cells and damage airway epithelium by causing A549 cell death.
CONCLUSIONS: Eosinophil autophagy and EETs could increase asthma severity by activating (AECs). Therefore, modulation of autophagy may be a new therapeutic approach for SA treatment.