Characterization of putative lin⁻CD117^−/loCD127⁻CD90⁻ BM-derived T-cell precursors. Flow cytometric analysis of lin⁻CD117^−/loCD127⁻CD90⁻ cells from BM. Cells were stained with antibodies against lineage markers CD90, CD117, CD127, CD27, and CD135 (A), and Sca-1 (B), CCR9 (C), CCR7 (D), or with P-selectin Ig to reveal expression of PSGL-1 (E). Cells from CCR9-deficient and CCR7-deficient mice were used as controls in panels C and D, respectively. For staining of PSGL-1, P-selectin-Ig was used in the presence (negative control) and absence of 10 mM EDTA (ethylenediaminetetraacetic acid). Numbers indicate frequencies of cells within gates. Data are representative of 2 independent experiments.