miR-29a/b-1-deficient HSCs exhibit reduced self-renewal and reconstitution capacity. (A-E) Donor cell chimerism of total peripheral blood leukocytes or specific cell lineages in the peripheral blood was examined following total bone marrow cell transplant. Donor chimerism (CD45.2⁺) levels were evaluated following transplantation of 2 million total bone marrow cells from WT, Het, or KO mice into lethally irradiated recipients. (F) Bone marrow cells from both femurs and tibias were examined for donor chimerism 20 hours after transplant using the same transplantation protocol used for competitive transplants. Each group includes 6 to 10 recipient mice transplanted with cells from >3 different donors. (G) Representative flow cytometric analysis of HSPCs in WT, Het, and KO recipients 16 weeks after transplant, previously gated on LSK cells. (H) Summarized results of flow cytometric analysis of bone marrow cells in recipients 4 months after the second transplantation. (I-M) Donor cell chimerism of secondary recipients transplanted with total bone marrow cells from primary recipients transplanted with WT or Het cells. (N) Flow cytometric analysis of HSPCs in the bone marrow of secondary recipients. Statistical significance was calculated using a Student t test: *P < .05; **P < .01.