FACS profiles of primitive murine and human BM cells. (A) Representative dot plots showing the gates used to isolate Sca-1⁺lin^– and lin⁺ populations of murine BM cells. (B) Representative dot plot showing the gates used to isolate CD34⁺ and CD34^– populations from low-density normal human BM cells. (C) Representative dot plot showing the gates used to isolate the CD38^– and CD38⁺ subsets of CD34⁺ cells from lin^– normal human BM cells.