Factors associated with granulocyte colony‐stimulating factor‐induced peripheral blood stem cell yield in healthy donors

Abstract

Background and Objectives Poor collection results are a clinical problem in granulocyte‐colony stimulating factor (G‐CSF)‐induced peripheral blood stem cell (PBSC) collection in healthy donors. It would be beneficial to be able to predict the PBSC yield from allogeneic donors before mobilization or harvesting. Materials and Methods We examined the relationship between certain donor characteristics and the effectiveness of G‐CSF‐induced PBSC collection in 59 healthy family donors aged 3–63 years old (median 16 years). G‐CSF was administered subcutaneously at 10 µg/kg for mobilization, daily for 5 days, and PBSC harvest using a continuous blood cell separator was started on day 5 of G‐CSF treatment. Total cell yields were calculated as the number per unit of processed blood (l) per unit weight of the donor (kg). Results In a univariate analysis, the donor's age, body mass index (BMI), white blood cell (WBC) count before mobilization, and platelet count before and during mobilization were significantly correlated with the yield of mononuclear cells (MNC), CD34⁺ cells and granulocyte–macrophage colony‐forming units (GM‐CFU). Younger age (P < 0·001), a low BMI (P = 0·002), a high WBC count before mobilization (P = 0·004), a high platelet count before (P = 0·012) and during (P < 0·05) mobilization, and a low speed of withdrawal (P = 0·019) were associated with a higher CD34⁺ cell yield. No significant correlation was found for gender, the type of G‐CSF, the serum level of G‐CSF, the type of cell separator, or the type of blood access. A multivariate forward and backward stepwise selection regression analysis showed that the factors associated with CD34⁺ cell yield were age, platelet count before and during mobilization, and circulating CD34⁺ cell concentration on day 2 of G‐CSF treatment. Conclusion In this small preliminary study, we found that donor age is the most important factor in predicting G‐CSF‐induced PBSC yields. Old age and low platelet counts before mobilization might be useful indicators for identifying poor mobilizers. Further validation of these findings in a larger number of donors are needed to establish whether these findings apply to other populations.