Decreased immune functions of blood cells following mobilization with granulocyte colony-stimulating factor: association with donor characteristics

In this study, mononuclear cells (MNCs) from granulocyte colony-stimulating factor (G-CSF)-mobilized blood stem cell (BSC) harvests from 104 healthy donors were analyzed for their immunological functions and compared with MNCs from 28 steady-state nonmobilized donors. The relationships between donor characteristics (age, gender, weight, and HLA type) and immune functions of the harvests were also analyzed. There was a significant (P < .01) decrease in natural killer and lymphokine-activated killer (LAK) cell-mediated cytotoxicity for G-CSF-mobilized effector cells compared with nonmobilized cells. Similarly, there was a significant (P < .005) decrease in both T-cell and B-cell mitogen response in G-CSF-mobilized cells compared with nonmobilized cells. There was dose-dependent inhibition of LAK cell-mediated cytotoxicity, but this effect was not seen with other immune function assays. Changes in immune function did not appear to be determined by frequency of cellular phenotypes or expression of effector function genes seen in a reverse-transcription polymerase chain reaction. There was a significant relationship between expression of certain HLA alleles (A1, A3, A24, B44, B62, DR15, DR17; all P < .01) and increased immune function, such as cytotoxicity and/or mitogen response. A decrease in immune function with the HLA-DR13 expression was also observed (P < .01). Since the G-CSF increases the number of MNCs, the increase in effector cells might compensate for decreased immune functions of these cells in vivo when transplanted into patients. These results suggest a decreased immune function in G-CSF-mobilized BSC harvests and warrant further studies to correlate these data with clinical outcome.