Differences in Mobilization Efficiency between Small Children and Adults with Healthy Marrows / 임상소아혈액종양

ABSTRACT

BACKGROUND: We compared the yields of mobilized PBSCs from single day of normal volume leukapheresis (NVL) in children and adults, and factors affecting the yields, to understand differences in mobilization efficiency between adults and small children with healthy marrows. METHODS: This study involved 18 adult volunteer donors and 47 small children weighing less than 20 kg who participated in a clinical trial of cell therapy in children with cerebral palsy. Donor factors analyzed to identify predictors of the yield of apheresis included age, gender, weight and complete blood cell count (CBC) with differential counts as well as equipment parameters. RESULTS: The yields of total nucleated cells (TNCs) and CD34⁺cells in the apheresis products of the children were significantly lower than in those from healthy adults. However, the efficiency of recovery of PBSCs (total CD34⁺ cell counts/TNCs) was significantly higher in small children (0.48±0.30%) than in adults (0.10±0.05%) (P < 0.05). Multivariable analysis of adult donor factors showed that the processed volume and flow rate of apheresis were significantly associated with the yield of TNCs (P < 0.05, for both), but not of CD34⁺cells. However, in multivariable analysis of child donor factors, body weight and circulating WBC count on the day of apheresis were significantly associated with the yield of TNCs (P < 0.05, for both) and of CD34⁺cells (P < 0.05, for both). CONCLUSION: The predictors of PBSC yields from a single day of NVL in adults and small children are different. Also mobilization is more effective in small children than in adults.