ICAM1 and acute respiratory distress syndrome: Consistent with this biology, higher circulating soluble ICAM-1 has been associated with worse outcomes in ARDS cohorts, supporting its role as a marker of clinically relevant endothelial injury [221], while soluble VCAM-1 is elevated in bronchoalveolar lavage fluid in ARDS, further linking endothelial activation to disease severity within the lung compartment [222].