Cxcr4¹⁰¹³-bearing HSPCs abnormally compartmentalize in the periphery. (A) Number of CFU-Cs in peripheral blood of WT, +/1013, and 1013/1013 mice. Data are from at least four independent experiments with 7–15 mice per group. (B) Number of CFU-Cs in the bloodstream of healthy individuals and WS patients carrying (R334X*, S338X*, and S339fs) or not (WHIM^wt) a disease CXCR4 allele. Lines indicate the mean and each symbol represent one subject. (C) Relative numbers of HSCs plus MPPs (Lin⁻CD45RA⁻CD38⁻CD34⁺, left) and immature lymphoid progenitors (MLP, Lin⁻CD45RA⁺CD38⁻CD7⁻CD34⁺CD10⁺, right) were determined by flow cytometry in the blood of healthy and WS subjects. (D) Numbers of LSK (left) or CFU-Cs (right) were determined in the blood of WT and mutant mice 1 h after intraperitoneal injection of AMD3100 (+) or PBS (−). Data are from two independent experiments with five mice per group. (E, left) Representative flow cytometric analyses comparing WT, +/1013, and 1013/1013 LSK SLAM frequencies in the spleen. (right) Absolute numbers of splenic LSK SLAM. Data are from at least five independent experiments with 9–15 mice per group. (F, left) Absolute numbers of CMPs, GMPs, and MEPs in the spleen. (right) Numbers of colonies formed from WT, +/1013, and 1013/1013 spleens in the myeloid lineage in CFU-C assays. Data are from at least four independent experiments with 7–15 mice per group. (G) Numbers of LSK SLAM, CMPs, GMPs, MEPs, and CFU-Cs in the spleen 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. (H) In vivo homing assays of CD45.2⁺ (WT, +/1013, or 1013/1013) BM cells into lethally irradiated CD45.1⁺ WT recipients. Absolute numbers of CD45.2⁺ Lin⁻ cells were determined by flow cytometry in the spleen of recipients 18 h after injection. Data are from two experiments with four to five recipients per group. (I) Proportions (left) and absolute numbers (middle and right) of donor CD45.2⁺ (WT, +/1013, or 1013/1013) LSK SLAM, CMPs, GMPs, and MEPs recovered from the spleen of BM chimeras in CD45.1⁺ (WT) recipients. Data are from at least three independent experiments with 6–12 recipient mice per group. All displayed results are represented as means ± SEM. Kruskal–Wallis H test–associated p-values (#) are indicated. Two-tailed Student’s t tests (A and D–I) or the Mann–Whitney U test (B and C) were used to assess statistical significance (*, P < 0.05; **, P < 0.005; and ***, P < 0.0005 compared with WT or CD45.2⁺ donor WT cells; ^§, P < 0.05; and ^§§, P < 0.005 compared with +/1013 or CD45.2⁺ donor +/1013 cells; ^&, P < 0.05 compared with PBS-treated mice).