Systemic CD95 engagement induces disseminated vascular endothelial cell death.

(A) The TUNEL assay shows apoptosis (brown staining) of vascular endothelial cells (filled arrowheads) and additional cell types in tissue sections from liver, heart, kidneys, and brain of wild-type (WT) mice killed 2 hours after injection of the JO2 CD95-specific antibody, whereas no apoptotic lesions were detected in CD95-defectivelpr (LPR) mice killed 6 hours after JO2 injection (the unstained endothelial cells are indicated by open arrowheads). (B) Endocardial lesions (heart) and subarachnoidal hemorrhage suffusions (brain), as well as typical electron microscopy features of endothelial cell apoptosis (kidney) were observed in wt mice killed 2 hours after JO2 injection (filled arrowheads).