ANGPT2 and acute respiratory distress syndrome: Ang2 (angiopoietin 2) is a ligand of endothelial receptor Tie2 and a key mediator of pulmonary vascular permeability and Day 7 Ang2 protein levels were an intermediate biomarker for ARDS mortality, a finding consistent with a recent meta-analysis that higher plasma Ang2 levels are predictive of mortality in both ARDS and at-risk patients31–34.