Effect of administration of an SDF-1 antagonist on the cycling of quiescent human HPP-CFCs in engrafted NOD/SCID mice.

Administration of an SDF-1 antagonist can reactivate the cycling of quiescent human HPP-CFCs in engrafted NOD/SCID mice. Data are from the same mice used for Figure 3, but in this case, the values are the mean ± SEM of the percentage killed as assessed after exposure of sorted human CD34⁺ cells to high–specific activity³H-thymidine for 20 minutes (or overnight for the LTC-ICs). Data marked by an asterisk indicate a significant difference from the control value (P < .001). The total colony counts in the control groups (no ³H-thymidine) ranged from 10 to 126.