Percentage of analyzed cells stained with annexin V and/or 7AAD
| 7AAD Annexin V . | − − . | − + . | + − . | + + . |
|---|---|---|---|---|
| EryP | 93 | 6 | 1 | 0 |
| Pyrenocytes | 49 | 35 | 3 | 13 |
| Treated marrow | 52 | 40 | 3 | 5 |
| 7AAD Annexin V . | − − . | − + . | + − . | + + . |
|---|---|---|---|---|
| EryP | 93 | 6 | 1 | 0 |
| Pyrenocytes | 49 | 35 | 3 | 13 |
| Treated marrow | 52 | 40 | 3 | 5 |
Significant numbers of pyrenocytes, but not orthochromatic erythroblasts (EryP), have lost phosphatidylserine asymmetry and therefore are annexin V–positive and 7AAD-negative. Bone marrow treated overnight with 0.5 μM staurosporine also reveals a large percentage (40%) of annexin V–positive, 7AAD-negative cells.