Cxcr4¹⁰¹³-bearing HSCs display disturbed homing, multipotency, and self-renewal capacities. (A) Absolute numbers of LSK SLAM, LT-HSCs, and ST-HSCs in the BM of middle-aged (56 wk old) WT, +/1013, and 1013/1013 mice. Data are from at least four independent experiments with 6–10 mice per group. (B) Bar graphs showing the percentage of LT-HSCs and ST-HSCs in the quiescent G0 phase (DAPI^lowKi-67⁻) in the BM of middle-aged mice. Data are from two independent experiments with five mice per group. (C) Proportions (left) and absolute numbers (middle and right) of CD45.2⁺ LSK and LSK SLAM from WT, +/1013, or 1013/1013 young (8–12 wk old) donor mice, recovered from the BM of chimeras in young CD45.1⁺ (WT) recipients after primary transplantation. Data are from at least three independent experiments with 8–15 recipient mice per group. (D) Serial transplantation of total donor CD45.2⁺ (WT, +/1013, or 1013/1013) cells recovered from the BM of primary BM chimeras in young CD45.1⁺ (WT) recipients. Proportions (left) and absolute numbers (middle and right) of donor CD45.2⁺ LSK and LSK SLAM were assessed in the BM of lethally irradiated CD45.1⁺ (WT) recipients 4 mo after secondary BM transplants. Data are from three independent experiments with 6–10 recipient mice per group. (E) Schematic diagram for in vivo homing assays of CD45.2⁺ (WT, +/1013, or 1013/1013) BM cells into lethally irradiated CD45.1⁺ WT recipients. (F) Absolute numbers of CD45.2⁺ LSK and LSK SLAM were determined by flow cytometry in the BM of recipients 18 h after injection. Data are from two experiments with four to five recipients per group. All displayed results are represented as means ± SEM. Kruskal–Wallis H test–associated p-values (#) are indicated. *, P < 0.05; **, P < 0.005; and ***, P < 0.0005 compared with WT or CD45.2⁺ donor WT cells; ^§, P < 0.05 compared with +/1013 or CD45.2⁺ donor +/1013 cells (as determined using the two-tailed Student’s t test).