CXCR4 inhibition recruits immature NK cells in BM sinusoids and the peripheral blood. Flow cytometric analysis of BM, LNs, and blood NK cells in WT mice treated for 1 hour with saline (control) or AMD3100 and injected intravenously with PE-conjugated anti-CD45 mAb for the final 2 minutes. (A) Mean ± SD percentage of CD45⁺ cells in gated NK cells in each group, as indicated. (B) Mean ± SD number of NK cells among PBMC (for 1 mL of blood) in each group, as indicated (n = 5 mice in each group). (C) Representative FACS plot of CD27/CD11b expression in gated CD45⁺ (sinusoidal) NK cells from BM and LNs and in gated blood NK cells in mice of each group, as indicated. (D) Mean ± SD percentage of CD45⁺ sinusoidal cells within each NK-cell subset and in mice of each group, as indicated (n = 5 mice in each group).