Fgd5 ^mCherry identifies cells with potent HSC activity. (A–E) Transplantation of 200 (A), 120 (B), 40 (C), 20 (D), or 5 (E) mCherry⁺ cells from Fgd5^mCherry/+ mice (red) or control LSKCD48⁻CD150⁺-sorted HSCs (HSC^Slam) from wild-type mice (black) showing total donor reconstitution (left) over the time course of transplantation, and lineage breakdown of donor cells in individual recipient mice at 16-wk after transplant (right). Asterisks (*) in E indicate mice that were not multilineage reconstituted at the 5-cell transplant dose. Granulocytes (GN), macrophage/monocytes (M), B cells, and T cells are indicated by color. (F) Mean total donor chimerism of each of the experiments shown in A–E. Error bars indicate SD, P > 0.05, by Student’s t test.