Sipa1^−/− hematopoietic cells failed to develop any hematological disorders after transplantation into young Sipa1^+/+mice. (A) Transplantation setup. The CD45.2⁺ cells from 8- to 10-week-old Sipa1^+/+ or Sipa1^−/− mouse BM were transplanted into lethally irradiated CD45.1 Sipa1^+/+ recipient mice (8-10 weeks old). Donor-derived lineages in the PB were analyzed by FACS monthly after transplantation. (B) Total donor engraftment in the recipient PB. (C) Red blood cells (RBC), hemoglobin (HGB), and platelets (PLT) in the recipient PB. (D) FACS analysis of blood lineage reconstitution after transplantation. The data are mean ± SEM, from 2 independent experiments, n = 9 to 10 per group. (E) H&E staining of PB smears of the Sipa1^+/+ recipients 9 months after transplantation of donor Sipa1^−/− or Sipa1^+/+ BM CD45.2⁺ cells. Scale bars represent 25 μm. (F) Reconstitution of HSPCs in the recipient BM 9 months after transplantation. CMP, common myeloid progenitor; LT-HSCs, long-term HSCs; ST-HSCs, short-term HSCs.