DNASE1 and chronic obstructive pulmonary disease: To investigate NETs’ role in glucocorticoid resistance, we established 4 experimental groups: the control group, the COPD group (exposed to CS for 2 months), the Dex group (COPD + 1 mg/kg Dex every 2 d, intraperitoneal), and the Dex+DNase I group (COPD + Dex + 5 mg/kg deoxyribonuclease I [DNase I] every 2 d, intraperitoneal).