In vivo functional characterization of Galc−/− HSPCs. (A) Experimental scheme for panels D through F. (B) Representative cytofluorimetric dot plots of GFP-transduced HSPCs and their negative control. (C) Frequency of GFP positive cells in the BM of FVB/Twi Galc−/− and +/+ recipients 20 hours after the transplantation of GFP+ Galc−/− and +/+ HSPCs (n = 4 for each group). (D) Survival curve of Galc−/− and +/− recipient mice (rec.) after the intraperitoneal transplantation of Galc +/+ or −/− HSPCs. (E-F) Engraftment failure frequency (E; defined as percent of animals showing a survival less than or equal to 21 days postirradiation, and/or less than or equal to 1% donor cells in the BM at death or at 120 postnatal days) and donor chimerism (% of GFP⁺ cell in the BM) at 120 days after transplantation or at mice death (F), measured in the same experimental groups as in panel D. Average values ± SD are reported. (G) Experimental scheme for competitive transplantation experiments (H-I). (H) Engraftment of Galc+/+ CD45.1⁺ and of Galc−/− CD45.2⁺ cells in peripheral blood of wild-type CD45.1 mice transplanted with HSPCs measured at 8 and 16 weeks (ws) after the transplantation (high or the low dose, see text for details; n = 6 for each group). Average values ± SD are reported. (I) Representative plots from cytofluorimetric analysis showing engraftment of CD45.1 and CD45.2 cells on peripheral blood of mice receiving competitive transplantation and GFP expression in each of the 2 populations.