TRANSPLANTATION In vitro migratory capacity of CD341 cells is related to hematopoietic recovery after autologous stem cell transplantation

To investigate whether the migratory ability of peripheral blood-derived CD341 cells of patients undergoing autologous peripheral blood stem cell transplantation is related to the homing efficiency of these cells, the migration in vitro of these cells was determined and correlated with in vivo hematopoietic recovery. Large interindividual differences of the in vitro migratory ability of the CD341 cells were observed, ranging from 1.1% to 16.4% for spontaneous migration and 6.2% to 40.8% for SDF-1–induced (100 ng/mL) migration. Significantly faster hematologic recovery was observed in those patients who received transplanted CD341 cells that showed high spontaneous and SDF1–induced migration in vitro (P < .05). Moreover, CD341 cells from healthy GCSF–mobilized donors exhibited significantly higher spontaneous and SDF-1– induced (P < .01) migration than CD341 cells from patients mobilized with chemotherapy and G-CSF. The lower migratory capacity in vitro of patient-derived CD341 cells was not due to lower expression of CXCR-4 but probably reflected decreased motogenic behavior of the cells. These results indicate that the migratory capacity of the cells is important for hematopoietic recovery. The data suggest that the engraftment potential of autologous stem cells is more or less impaired by treatment before or during the mobilization procedure and might possibly be restored by in vitro manipulation of the cells. In addition, an exponential relation between CXCR-4 expression and number of CD341 cells that mobilized to the peripheral blood was found (P < .001), suggesting that CXCR-4 expression plays a role in the mobilization of CD341 cells. (Blood. 2001;97:799-804)