Additionally, given that endothelin-1 (ET1) levels, one of two DEspR ligands21, are elevated in ARDS22, and since ET1 is known to enhance neutrophil activation and functionality23, ET1-mediated DEspR activation could play key pathogenic role(s) in neutrophil-mediated secondary tissue injury in ARDS. The gene discussed is EDN1; the disease is acute respiratory distress syndrome.