Figure 2.

Lung histology from ARDS and control patients. Representative photomicrographs of distal airway and alveolar tissue from ARDS (A and C) and control (B and D) patients. ARDS lungs show extensive intra-alveolar exudate (A) and small airway thickening with mild inflammation and epithelium denudation (C). SA = airway; L = lumen; EP = epithelium; SM = smooth muscle; OL = outer layer; IL = inner layer. H&E staining. Scale bars: A and B = 100 μm, C and D = 50 μm.