Phenotype and clonogenic potential of Galc−/− HSPCs. (A-F) Immunophenotypic characterization of the BM of Galc−/− mice. Frequency and absolute cell number (#) of c-kit⁺ Sca1⁺ cells within lineage⁻ (Lin)⁻ BM cells (KLS; A), and of long-term HSC (LT-HSC), MPP1, MPP2, and GMLP (within the KLS fraction) of −/− and +/+ mice (B). Frequency of lymphoid and myeloid progenitors within Lin⁻ cells (C) of wild-type and mutant mice. Lymphoid (D), erythroid (E), and myeloid (F) differentiation in −/− and +/+ BM. Each dot represents a pool of 3 mice in panels A through C and a single mouse in panels D through F; means are shown. For details on the gating strategy, please see supplemental Table 1. (G-H) Frequency of proliferating cells at Hoechst staining (G) and of apoptotic annexin V positive cells (H) within KLS, LT-HSC, MPP1, MPP2, and GMLP from +/+ and −/− mice. Each dot represents a pool of 3 mice; means are shown. (I-J) Number (#) of colonies retrieved from colony-forming cell assays performed with murine (I) and human (J) HSPCs from wild-type (Galc+/+ and Arsa+/+), Galc−/− and Arsa −/− mice, and from normal donors' (nd) and GLD/MLD patients' BM. Before plating, murine HSPCs were (w) or were not (w/o) prestimulated with a standard cytokine cocktail for 12 hours.¹²  n ≥ 10 (murine) and n ≥ 3 (human). *P < .05, **P < .01 on 1-way ANOVA.