Myeloid cell-specific p53 deficiency impairs venous thrombus resolution. (A) Thrombus weights of Mp53^+/+ and Mp53^−/− mice 12 days after vena cava ligation (n = 7 Tp53^+/+ and 6 Tp53^−/−). *P < .05, Mp53^+/+ vs Mp53^−/− mice. (B) Intrathrombotic F4/80 mRNA expression at 12 days after vena cava ligation in Mp53^+/+ and Mp53^−/− mice, determined by qPCR. All values represent the mean ± SEM (n = 4 Tp53^+/+ and 4 Tp53^−/−). (C) Intrathrombotic mRNA expression of macrophage polarization markers at 12 days after vena cava ligation in Mp53^+/+ and Mp53^−/− mice, as determined by qPCR. All values represent the mean ± SEM (n = 4 Tp53^+/+ and 4 Tp53^−/−). *P < .05, Mp53^+/+ vs Mp53^−/−. (D) Histochemical analysis of intrathrombotic collagen content by Picrosirius Red staining at day 12 after vena cava ligation; original magnification ×100. Representative images from 4 to 5 independent mice of each genotype are shown. The intrathrombus collagen area was quantitated as a measure of fibrosis as described in “Methods.” All values represent the mean ± SEM (n = 5 Tp53^+/+ and 4 Tp53^−/− n= 4-5). *P < .05, p53 Mp53^+/+ vs Mp53^−/−.