Blood cell TF is indispensable for venous thrombosis. (A) Fibrin formation during DVT development was measured in vivo by intravital microscopy in control HCV and low-hTF mice using an Alexa Fluor 488–labeled specific fibrin antibody. Measurements were performed after 1–6 h of flow restriction. Representative images acquired by intravital microscopy of the IVC are shown on the right (fibrin pseudocolored in yellow). Bars, 100 µm. n = 3 per group. Data are shown as mean ± SEM. (B) Thrombus load was assessed on vG-stained serial sections in low-hTF (n = 10) and HCV mice (n = 5), as well as in bone marrow chimeras lacking blood cell TF (n = 6). Thrombus load is given as square millimeters. Dots represent individual experiments; lines show the mean of each group. (C) Assessment of leukocyte recruitment 6 h after flow reduction by intravital microscopy. Leukocytes were visualized using i.v. application of the fluorescent dye rhodamine 6G (pseudocolored in green). The number of adherent cells is given as number per square millimeters (n = 3 per group). Representative in vivo images are shown on the right. Bar, 100 µm. Data are shown as mean ± SEM. (D) Thrombus weight (at 48 h) in control mice (n = 10) and in conditional mutants (LysM^Cre-TF^flox/flox) lacking TF in LysM⁺ myeloid cells (n = 12). Dots represent individual experiments; lines show the mean of each group. (E) Immunohistochemical detection of TF protein (red) on Ly6G-positive (green) and -negative cells in thrombi at 48 h of flow restriction, indicating TF expression on neutrophils (yellow; TF⁺ and Ly6G⁺) and monocytes (red; TF⁺ and Ly6G⁻). LysM^Cre-TF^flox/flox mice (bottom) were used as negative control. Nuclei are stained with DAPI. Bars, 100 µm. Shown is a representative of n = 3 experiments.