CCR7^−/− mice have increased numbers of HSCs and GMPs compared with WT controls. (A) CCR7 gene expression from FACS-sorted WT CMPs and GMPs were analyzed by real-time PCR (values represent CCR7 amplification cycle, compared with GAPDH). (B-E) Markers for HSCs were lineage⁻, c-Kit⁺, Sca-1⁺, and CD34⁻. CMPs were lineage⁻, c-Kit⁺, Sca-1⁻, CD34⁺, and CD16/32 low. GMPs were identical to CMPs, but were CD16/32 high. (B) HSC, CMP, and GMP numbers and percentages from BM of naïve WT and CCR7^−/− mice. (C) Flow cytometric plots of lineage⁻ BM from naïve WT and CCR7^−/− mice. C-Kit⁺, Sca-1⁺, and lineage⁻ cells (left graphs) were analyzed for the expression of CD34 (right graphs). (D) Flow cytometric plots of total MPCs show similar percentages between WT and CCR7^−/− mice, but differences in the percentages of CMPs and GMPs. (E) HSC, CMP, and GMP numbers and percentages from the spleens of naïve WT and CCR7^−/− mice (n = 3-5 mice per group, representative of more than 5 experiments). *P < .05, when comparing WT and CCR7^−/− HSCs and MCPs.