TIMP-3 facilitates hematopoietic recovery from BM suppression in vivo. (A) Mice (n = 4 for each group) were injected with 5-FU intraperitoneally on day 0 and then with TIMP-3 expression plasmids through tail veins by hydrodynamic delivery on day 1. (Top left) Experimental schedule. (Top right) Graphs for white blood cell (WBC) counts (initial counts at day 0 are regarded as 100% for each animal). Data are mean ± standard error (SE). *P < .05. (Bottom left) Bone marrow cellularity of animals injected with control or TIMP-3 plasmids (day 4). Hematoxylin staining. Original magnification ×200. (Bottom right) Total number of BM cells (from both femurs) at day 4 was counted and shown (mean ± SE, n = 3, *P < .05). (B) Survival curves of irradiated (900 R) mice treated with TIMP-3. Mice were injected with control or TIMP-3 plasmids 24 hours after irradiation. The curves are statistically different (n = 9 per group, P < .05 by log-rank test). (C) Impaired BM recovery of TIMP-3 deficient mice (TIMP-3^−/−). TIMP-3^−/− mice and the wild-type littermate controls were treated with 5FU (150 mg/kg, intraperitoneally). White blood cell and platelet counts were monitored at the indicated time points. Data are mean ± SE (n = 5 for wild-type and n = 3 for TIMP-3^−/−, *P < .05).