Repopulation kinetics of subsets of pluripotent hematopoietic stem cells (PHSC).

Bone marrow transplantation (BMT) was performed as follows: 100 Ly5.1 donor cells (from 1 of the 3 subsets, 38⁺34⁻[●], 38⁺34⁺ [■], or 38⁻34⁺ [▴]) and 2 × 10⁵Ly5.2 whole BM competitor cells were transplanted into Ly5.2 lethally irradiated mice. Blood samples were collected at the indicated times after BMT and examined for the presence of Ly5.1 multilineage reconstitution (marked on y-axis). The data suggest that all 3 subsets have short-term multilineage reconstituting ability but that only the 38⁺34⁻ subset of PHSC has marked long-term reconstituting ability. T indicates T lymphocytes; B, B lymphocytes; M, macrophages; and G, granulocytes. Data are from 2 independent experiments using 3 to 6 mice per group in each experiment; the values presented are means ± SE.