Background: Allogeneic blood cell transplantation is a new alternative to bone marrow transplantation. Preliminary data suggest that granulocyte-colony-stimulating factor (G-CSF)-mobilized peripheral blood progenitor cells from normal donors can provide rapid hematopoietic engraftment without significant increases in transplant-related morbidity. Potential advantages to donors include the elimination of an operation under general anesthesia.
Study design and methods: Twenty-one normal donors underwent high-dose (16 pg/kg/day for 5 days) G-CSF mobilization. Apheresis was performed on the fifth and sixth days of G-CSF administration, and apheresis components were analyzed by flow cytometry. Donor characteristics in relationship to apheresis yields were also analyzed.
Results: Apheresis components were analyzed according to donor weight. The median total numbers of white cells per kg, CD34+ cells per kg, and CD3+ cells per kg were 10.8 x 10(6), 7.2 x 10(8), and 295 x 10(8), respectively. Day 5 collections had significantly higher nucleated cell content and median CD34+ percentages than did Day 6 collections (0.71% on Day 5 vs. 0.58% on Day 6, p < 0.01). CD34+ content and total white cells were not related to age or sex. No donors experienced toxic effects that required their removal from the study.
Conclusion: Day 5 is the optimal day for the harvest of normal-donor peripheral blood progenitor cells after mobilization with high-dose G-CSF. Older individuals are acceptable donors of allogeneic progenitor cells.