Representative dot plot of murine BM cells stained with fluorescently conjugated antibodies that recognize c-kit (y axis) and the following lineage markers: B220, CD3, or CD11b (x axis) (A). The locations for the quadrant markers were set based on background, nonspecific staining using an irrelevant fluorescently conjugated antibody. (B) Representative dot plot of MC540 staining of c-kit⁺lin⁻ gated cells (upper left-hand quadrant of dot plot in [A]). The fluorescence intensity of MC540 staining is plotted on the y axis against side scatter on the x axis. The MC540 gate to distinguish MC540^bright, apoptotic cells from MC540^dim, viable cells was determined by identification of viable and apoptotic cells from a forward versus side scatter analysis.