Comparison of Single- and Dual-Platform Approaches to Enumerate CD34+ Cells in Bone Marrow and Mobilized Peripheral Blood Stem Cells

Background ent flow cytometric methods have been developed to derive absolute CD34+ cells in predicting transplant outcome. Two techniques for preparing cells for quantification of CD34+ cells were compared. s ation of CD34+ cells in 16 samples of bone marrow (BM) and in 29 samples of mobilized peripheral blood stem cells (PBSC) obtained by leukapheresis was assessed simultaneously by single-platform (ProCOUNT kit) and dual-platform (Milan protocol) approaches within the first 3 h of collection. s te number of CD34+ cells obtained in PBSC and BM using single- and dual-platform methods showed high determination coefficients as follows: for PBSC, slope = 1.0515 ± 0.048, y-intercept = 88.638 ± 52.45, and r2 = 0.941, and for BM, slope = 1.0203 ± 0.093, y-intercept = 122.25 ± 20.65, and r2 = 0.878. There were no statistically significant differences in absolute number of CD34+ cells from PBSC between single-platform (mean 575/μL, range 70–3,683/μL) and dual-platform (786/μL, range 51–3,804/μL) assays. In contrast, absolute number of CD34+ cells from BM was significantly lower (p = 0.0002) when enumerated by ProCount kit (135/μL, 14–758/μL) than with dual-platform method (260/μL, 74–889/μL). sions pproaches can be used indistinctly to estimate absolute number of CD34+ cells in PBSC but not in BM.