Assessment of factors affecting mobilization and collection in autologous and allogeneic hematopoietic stem cell donors

Abstract

Background & Aim Background Peripheral blood hematopoietic stem cells (PBSC) are preferred source of stem cells in the majority of autologous and allogeneic transplantations. Sufficient number of mobilized and collected hematopoietic stem cells (HSC) is needed for successful transplantation. The aim of our study was to analyze possible predictive factors that could influence hematopoietic stem cell yield. Methods, Results & Conclusion Methods This study was performed in the Institute for Transfusion Medicine of RM and the University Hematology Hospital. There were 30 allogeneic and 90 autologous donors that underwent mobilization and collection of PBSC. The association between the number of collected PBSC and possible predictive factors was analyzed using Spearman Rank Order Correlation. Results There were 226 apheresis, 182 in autologous donors (mean 2, range 1-3) and 44 apheresis in 30 allogeneic donors (mean 1.5, range 1-2). The mean number of collected MNC in autologous donors was 3.09 × 108/kg and 2.85 × 106/kg CD34+ cells, and 3.23 × 108/kg MNC and 3.20 × 106/kg CD34+ cells in allogeneic donors. Significantly larger number of MNC and CD34+ cells was collected with the WBC set. There was a statistically significant correlation between the total number of collected MNC in autologous donors and platelet count before mobilization, the number of cycles in one apheresis procedure, quantity of collected graft and the number of collected MNC and CD34+ cells on the first day of apheresis. There was a statistically significant correlation between the total number of collected MNC in allogeneic donors and platelet count before mobilization, the number of cycles in one apheresis procedure, quantity of collected graft and number of MNC on the first day of apheresis. There was a strong correlation between the number of collected MNC and CD34+ cells on the first harvest and the total number of collected MNC and CD34+ cells in poor mobilizers, and inverse correlation with the number of apheresis procedures. Donors who donated MNC ≤ 0.7 × 108/kg and/or ≤ 0.7 × 106/kg CD34+ cells on the first harvest (84.6%) were strong predictors of poor mobilizers. Conclusion Determining the proper level of laboratory parameters for initiating mobilization and apheresis procedure which is safe for donors and efficient in collection of PBSC is needed for optimization of these procedures, as well as for early intervention in poor mobilizers.