Highly specific functional equivalence of XN-HPC for optimum CD34+ cell count in harvested allogeneic bone marrow stem cell products

To establish a reliable XN-HPC cutoff, for an effective CD34 + cell count of ≥2 × 10 6 cells/kg of the recipient's body weight, in harvested bone marrow products in allogenic transplantation. The study was carried out in two phases. In retrospective Phase 1, data from 47 donors were analyzed. Sysmex analyzer XN-20 and BD FACS Calibur were employed to process XN-HPC and CD34 + cell enumeration, respectively. To make the two variables comparable, both XN-HPC and CD34 + cell counts were reported as the number of cells/kg of the recipient's body weight. Spearman's rank correlation coefficient was calculated for CD34 + cells and XN-HPC, followed by the calculation of the receiver operating characteristic (ROC) curve to identify the XN-HPC value which could effectively predict the cutoff of ≥2 × 10 6 CD34 + cells/kg of the recipient's body weight. In Phase 2, the computed XN-HPC cutoff was validated in a prospective set of 53 donors by obtaining the positive and negative predictive values. Statistically significant correlation was obtained between XN-HPC and CD34 + cell count with Spearman's rho of 0.54 (p-value