Predictive parameters for granulocyte colony-stimulating factor-induced peripheral blood stem cell mobilization

To improve the selection of donors for allogeneic stem cell transplantation, it is important to identify reliable parameters that predict CD34+-cell yields after granulocyte-colony stimulating factor (G-CSF)-induced peripheral blood stem cell (PBSC) mobilization. We retrospectively investigated the peripheral blood (PB) kinetics of white blood cells (WBCs), CD34+ cells, matrix metalloproteinases (MMP)-9 and -2, and tissue inhibitors of metalloproteinases (TIMP)-1 and -2 in 15 healthy donors during their treatment with G-CSF. All donors received 10 microg/kg of recombinant human G-CSF once a day subcutaneously. Leukapheresis was initiated after 4 days of G-CSF treatment, and G-CSF treatment continued until the last day of leukapheresis. WBC and CD34+ cell numbers in the PB rose after 2 and 3 or 4 days of G-CSF treatment, respectively. The PB CD34+ cell numbers on day 4 correlated weakly with the increase in WBC counts from day 1 to day 2 (R(2) = 0.254, P = 0.056). There were also positive correlations between the CD34+ cell numbers in the PBSC products on day 4 and the CD34+ cells in the PB on days 1 and 4 (R(2) = 0.768, P < 0.0001 and R(2) = 0.816, P < 0.0005, respectively). The MMP-9 plasma levels on days 1 and 4 also correlated positively with the day 4 circulating CD34+ cell numbers (R(2) = 0.393, P < 0.05 and R(2) = 0.406, P = 0.01, respectively). In conclusion, the CD34+ cell numbers in the PB steady state may be a useful parameter selecting allogeneic PBSC donors.