In vivo role of Gas6 in inflammation and thrombosis. (A,B) CD45 staining in lungs of WT and Gas6^−/− mice 4 hours after intraperitoneal injection of 20 mg/kg LPS showed higher neutrophil extravasation in the lung parenchyme of WT mice (A) compared with Gas6^−/− animals (B). (C-D) CD45 immunostaining in footpads of WT and Gas6^−/− animals, injected with 50 μg LPS, revealed extensive inflammation in the adventitial and muscle area of WT animals (E), whereas vessels in Gas6^−/− animals were less inflamed (D). (E,F) Hematoxylin and eosin staining in footpads of WT and Gas6^−/− animals, injected with 50 μg LPS, revealed the presence of large, organized thrombi covering most of the lumen in veins of WT animals (E), whereas vessels in Gas6^−/− animals contained fewer and smaller thrombi (F). Magnification bar represents 50 μm in all panels.