Fibroblast and ROCK1 staining in lung sections from COPD patients. Representative micrograph from one COPD patient that show immunostaining with antibodies against ROCK1, vimentin and prolyl-4 hydroxylase. Antibodies were visualized by DAB (shown in brown) and sections were counterstained with Mayer’s hematoxylin, which stains cell nuclei blue. (A) showsROCK1 staining. Asterisks indicate the bronchiolar epithelium. Smooth muscle cells are indicated by open arrowheads. (B) shows vimentin staining. Open arrowhead show smooth muscle cells. (C) shows prolyl-4 hydroxylase staining. Asterisks show immuno-positive bronchiolar epithelial cells. Alveolar type II cells are indicated by open arrowheads. Inserts show subepithelial, elongated, spindle-like immuno-positive cells (indicated by closed arrowheads). Scale bars represent 50 μm of the larger image and 10 μm on inserts.