Mobilization of dendritic cells and NK cells in non-Hodgkin's lymphoma patients mobilized with different growth factors

Conflicting results have been reported regarding the effect of various growth factors on the mobilization of natural killer (NK) cells and dendritic cells in patients undergoing stem cell mobilization for autotransplantation. We compared the extent of mobilization of NK cells and dendritic cells in non-Hodgkin's (NHL) patients undergoing mobilization with granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage (GM)-CSF, or GM-CSF followed by G-CSF. Overall, 35 patients were studied. NK cells and dendritic were quantitated by flow cytometry. NK cells were defined as the sum of CD56⁺ cells and CD56/CD16⁺ cells. Dendritic cells were defined as the sum of CD80⁺ and CD80⁺/CD14⁺ cells. NK activity was determined by by microcytotoxicity assay. NK activity correlated well with the total amount of CD56⁺ cells mobilized to the peripheral blood. Patients in the three arms of the study mobilized similar amounts of NK cells and NK activity, and patients who lacked NK activity in the peripheral blood, before mobilization, lacked NK activity in their apheresis collections. In contrast to NK cell mobilization, mobilization of dendritic cells/kg was three- to five-fold higher in patients mobilized with GM-CSF-containing regimens compared to patients mobilized with G-CSF alone. We conclude that GM-CSF-containing mobilization regimens are superior for dendritic cell mobilization but similar in the mobilization of NK cells. Therefore, we recommend using GM-CSF-containing regimens for patients undergoing ex vivo or in vivo manipulation of dendritic cells.