MALT1 inhibition protects against venous thrombosis induced by flow restriction. C57/BL 6J wild-type mice were administered 2 doses of MALT1 inhibitor, mepazine (12.5 mg/kg body weight each dose, intraperitoneally), the first dose 2 hours before surgery, and a second dose 24 hours after the IVC ligation. Control mice were administered with a control vehicle (DMSO). Mice were subjected to the IVC ligation-induced stenosis. Forty-eight hours following the IVC ligation, mice were killed, and thrombus formation in the ligated vein was evaluated. (A) Representative images of thrombus; (B) thrombosis prevalence; (C) thrombus length; (D) thrombus weight. Thrombi collected were processed for tissue sectioning, and sections were stained with antibodies against (E) Ly-6G or (F) F4/80 antigens. The sections were visualized under a bright field microscope at 10×, and selected areas (boxed) were viewed at 40× magnification. The number of LY-6G or F4/80-positive cells was analyzed at 10 randomly chosen areas of the high-power field covering the entire section of 10 different mice. Data are mean ± standard deviation of 3 independent experiments. *P < .05, **P < .01, and ***P < .001.