Immunohistochemical analyses of wild-type and Pecam-1−/−thrombi illustrating misguided vascular remodeling of thrombus resolution in the absence of PECAM-1. Isolectin-B4 immunoreactivities representing endothelial cells in wild-type (A-D) and corresponding Pecam-1−/− thrombi (E-H) are shown on days 3 (A,E), 7 (B,F), 14 (C,G), and 28 (D,H) after vena cava ligation on the left side of the panel. The right side of the panel shows F4/80 immunoreactivities representing macrophages (examples of immunopositive cells are pointed out with small arrows) in wild-type (I-L) and corresponding Pecam-1−/− thrombi (M-P) on days 3 (I,M), 7 (J,N), 14 (K,O), and 28 (L,P) after vena cava ligation. Scale bar, 100 μm.