TKO bone marrow can reconstitute and outcompete Bid^+/+bone marrow but is unable to maintain long-term hematopoiesis. (A) Percentage of CD45.2⁺ cells in Bid^+/+, DKO, and TKO transplant mice at 8, 12, 16, and 20 weeks after transplantation. Mice were transplanted with experimental and control bone marrow at a 1:1 ratio. Bid^+/+, n = 7; DKO, n = 7; and TKO, n = 6. Statistics demonstrate differences between Bid^+/+ and TKO animals. (B-D) RBCs (10⁶/µL; B), platelet counts (10³/µl; C), and mean platelet volume (fL; D) in transplanted Bid^+/+ and TKO mice at 8, 12, 16, and 20 weeks after transplantation. Bid^+/+, n = 5; TKO, n = 8. Statistics demonstrate differences between Bid^+/+ and TKO animals. (E) Distribution of myeloid progenitor, LSK, and SLAM-HSC populations in Bid^+/+, DKO, and TKO transplanted mice. Bid^+/+, n = 5; DKO, n = 7; and TKO, n = 6. (F) CD45.2⁺ LSK cells in transplanted mice. (G) Secondary transplantation of DKO and TKO bone marrow (primary transplant in a 1:1 ratio with Bid^+/+) to rigorously test hematopoietic stem cell function. DKO, n = 8; and TKO, n = 7. (H) Ratio of the colony-forming ability of CD45.1⁺ to CD45.2⁺ cells isolated from primary transplants. Bid^+/+ or TKO CD45.2⁺ cells are transplanted in a 1:1 ratio with congenic CD45.1⁺Bid^+/+ cells. CD45.1⁺ and CD45.2⁺ bone marrow cells were sorted and cultured in methylcellulose in the presence of IL3, IL6, SCF, EPO. Colonies were counted at 10 days. The data are from 3 independent experiments. (I) Number of colonies for indicated bone marrow cells relative to Bid^+/+ colonies. Bid^+/+ CD45.1 denotes WT CD45.1 cells transplanted with Bid^+/+ CD45.2 cells. TKO CD45.1 denotes WT CD45.1 cells transplanted with TKO CD45.2 cells. ns, not significant; *P < .05 **P < .01, ***P < .001, and ****P < .0001. Data represent mean ± SEM.