TSP2-null denuded aortic grafts resist thrombosis. Aortic segments from WT and TSP2 KO mice were denuded and grafted in WT mice. Representative images of hematoxylin-and-eosin (H&E)-stained sections of grafts 48 hours following surgery are shown. WT to WT graft (A) is completely occluded whereas the KO to WT graft is fully patent (B) (Zeiss). (C-D) Representative images of WT (C) and TSP2 KO (D) aortic segments immunostained for PECAM-1 (brown color) are shown and demonstrate lack of endothelium. Arrow in D denotes remnants of endothelium. (E-F) Representative images of WT (E) and TSP2 KO (F) aortic segments immunostained for TSP2 (brown color) are shown and demonstrate presence and absence of TSP2, respectively. Arrows in E denote TSP2-immunoreactive cells. (G-H) Representative images of immunofluorescence detection of VWF (green color) in WT (G) and TSP2 KO (H) aortic segments are shown (Zeiss). WT segments show excessive VWF immunoreactivity in the area of thrombus formation, which is absent in TSP2 KO grafts. Asterisk (*) denotes lumen area; arrows denote the vessel edge. Sections were counterstained with methyl green (A-F) or DAPI (G-H). n = 5.