Flow cytometric analysis of the surface-marker–expression profile of murine bone marrow (BM) cells.

Lineage-positive cells were removed by CS column before flow cytometry. (A) Expression of Sca-1 and c-kit on the cell surface was gated as shown; Lin⁻ Sca⁺ kit⁺cells were gated as shown in box A. (B) Expression of CD38 and CD34 on the cell surface of the Lin⁻ Sca⁺kit⁺ cells was used to separate the cell population shown in box A in Figure 1A into the following 4 subsets: Sca⁺kit⁺ CD38⁺ CD34⁻(38⁺34⁻), Sca⁺ kit⁺CD38⁺ CD34⁺ (38⁺34⁺), Sca⁺ kit⁺ CD38⁻CD34⁺(38⁻34⁺), and Sca⁺kit⁺ CD38⁻ CD34⁻(38⁻34⁻). Two other subpopulations examined (Figure 3) were Sca⁺ kit⁺ CD38⁺CD34^lo (38⁺34^lo) and Sca⁺ kit⁺ CD38⁻ CD34^lo(38⁻34^lo) (rectangular gates). Cells in each population were sorted and collected for analysis in a competitive repopulation assay.