Quinacrine treatment alters intrathrombotic macrophage polarization and fibrosis. (A) Intrathrombotic mRNA expression of macrophage polarization markers at day 12 after vena cava ligation following treatment with vehicle or quinacrine, as determined by qPCR. All values represent the mean ± SEM (n = 4 vehicle and 4 quinacrine). *P < .05, vehicle vs quinacrine. (B) Intrathrombotic expression of IL-6 mRNA at day 12 after vena cava ligation following treatment with vehicle or quinacrine by qPCR. Values represent the mean ± SEM (n = 4 vehicle and 4 quinacrine). *P < .05, vehicle vs quinacrine. (C) Intrathrombotic expression of IL-6 protein at day 12 was determined by ELISA. All values represent the mean ± SEM (n = 4 vehicle and 4 quinacrine). **P < .05, vehicle and vs quinacrine. (D) Histochemical analysis of intrathrombotic collagen content by Picrosirius Red staining after treatment with vehicle or quinacrine at day 12 after vena cava ligation; original magnification ×100. Representative images from 4 to 5 independent mice of each group. The intrathrombus collagen area was quantified as a measure of fibrosis as described in “Methods.” All values represent the mean ± SEM (n = 4 vehicle and 5 quinacrine). *P < .05, vehicle vs quinacrine treated. (E) Effect of quinacrine treatment on established thrombi. CD-1 mice were treated with vehicle or quinacrine from 3 days post–vena cava ligation, and thrombus weights measured at 12 days after vena cava ligation (n = 8 vehicle and 9 quinacrine). *P < .05, vehicle vs quinacrine.