Blockade of endothelial NF-κB signaling attenuated coagulation and improved survival. (A-B) Endothelial NF-κB blockade restored plasma fibrinogen level and reduced plasma D-dimer level. Plasma was collected from WT-Con (W-C), WT-LPS (W-L), TG-Con (T-C), and TG-LPS (T-L) groups of mice at 6 hours after saline or LPS injection. Plasma levels of D-dimer and fibrinogen were determined using commercial kits. Data are mean ± SEM of 6 mice. *P < .001 compared with any other group. #P < .001 compared with the WT-LPS group. (C) Endothelial NF-κB blockade improved survival. WT and TG mice were injected with LPS (5 mg/kg intraperitoneally) and followed for 14 days (no further mortality after 7 days). *P < .001, compared with WT mice (log-rank test, 20 mice per group). (D-O) Endothelial NF-κB blockade reduced tissue fibrin deposition. Paraffin-embedded sections were prepared at 6 hours after saline or LPS injection, dewaxed, rehydrated, blocked, reacted with fibrin/fibrinogen-specific antibody, and counterstained with hematoxylin. The dark brown horseradish peroxidase reaction product shows fibrin deposition in microvasculature and arterioles of heart (J), liver (K), and kidney (L) sections from WT-LPS mice. No fibrin deposition was observed in the 3 organs of WT-Con (D-F) and TG-Con (G-I) mice. The dark brown staining was significantly reduced in tissue sections from TG-LPS (M-O) mice. Bar represents 85 μm. Slides were viewed with an Olympus BH2 microscope (Olympus America) using an Splan 40PL lens at 40×/0.70 and Permount mounting medium (Fisher Scientific). Images were acquired using a Nikon DS camera (model DS-U2 cooled), and were processed with Nikon NIS-Elements basic research software and Adobe Photoshop Version 7.0 software.