Annexin V/propidium iodide dual staining of BLIN-2 cells cultured in the presence (A) or absence (B) of BM stromal cells for 4 days. BLIN-2/stromal cell cultures were gently shaken to displace BLIN-2 from the stromal cells. These stromal cell-displaced BLIN-2 cells and BLIN-2 cells in medium alone were then stained with propidium iodide and FITC-conjugated Annexin V. The numbers represent the percentage of propidium iodide⁺/Annexin V⁺or propidium iodide⁻/Annexin V⁺ cells as a function of total cells analyzed.