A study to compare Hematopoietic Progenitor Cell count determined on a next‐generation automated cell counter with flow cytometric CD34 count in peripheral blood and the harvested peripheral blood stem cell graft from autologous and allogenic donors

Abstract

Introduction A successful bone marrow transplant requires a minimum of 2‐4 × 106 cells/kg patient body weight of CD 34+ cells to be transfused, where peripheral blood CD34+ cell count being and ideal predictor. We compared the correlation and predictive capacity of both hematopoietic progenitor cell count (HPC) determined on the Sysmex XN‐9000 and flow cytometric CD34 in autologous and allogenic donors. Methods Autologous and allogenic donors were taken as per criteria. TLC (Total Leukocyte Count), MNC (Mononuclear cell count), HPC, and CD34 assay were done in both the peripheral blood prior to apheresis, and the harvest product postapheresis. Sysmex XN‐9000 was used for TLC, MNC, and HPC tests, and a modified ISH‐AGE protocol was used to enumerate CD34 by flow cytometry. Statistical analysis was done using SPSS 16.0. Results Sixty‐seven allogenic and 35 autologous donors were enrolled. 45% were females, and 55% were males. Correlation between HPC and CD34 was found to be 0.887 with P value < .01 in peripheral blood and 0.847 with P value < .01 in the harvested product. On the other hand, TLC had a correlation of 0.424 and 0.520 in peripheral blood and harvested, respectively. MNC had a weak association. The cutoff value for a target dose of 2 × 106 CD34 cells/kg was 37 × 106/L for pre‐HPC. For a target of 4 × 106 CD34 cells/kg, the cutoff value calculated to be 54 × 106/L (Sensitivity: 85%, Specificity: 89%) for peripheral blood HPC. Conclusion We conclude that HPC is comparable to CD34 in predicting harvest product's adequacy.

Correlation between peripheral blood automated hematopoietic progenitor cell counts and flow cytometric CD34+ cell counts differs according to diagnosis in patients undergoing autologous peripheral blood stem cell transplantation

“…An overestimation in XN‐HPC count was noted (SMC, 1.6‐fold; HSC registry, 1.3‐fold), which was also observed in previous studies, 8,13‐15 especially in autologous transplantation 8,26 . The correlation between XN‐HPC and CD34 + cell count in our study was relatively poor compared to previous studies 8,9,11,12 .…”

“…In this study, we only included cancer patients undergoing autologous PBSC transplantation. For autologous transplantation, the correlation between XN‐HPC and CD34 + cell count was moderate both in the study of Söderström et al 15 (n = 61; PB sample, r = 0.75; apheresis product sample, r = 0.64) and Mishra et al 14 (n = 35; PB sample, r = 0.66), but was excellent in the study of Furendarena et al 8 (n = 50; PB sample, r = 0.977).…”

“…The result is reported within 5 min with the additional advantages of less labor and cost. A number of studies have evaluated whether the XN‐HPC count could be an effective tool for predicting adequate stem cell harvest 8‐15 . Compared to the previous SE‐ and XE‐analyzers showing poor to moderate correlation ( r = 0.44 to 0.74), 16‐20,25‐27 the XN analyzer demonstrated an improved correlation with CD34 + cell count ( r = 0.65‐0.98) 8,10‐15 …”

“…To the best of our knowledge, our study includes the largest number of patients (SMC, 171; HSC, 228) among the published studies evaluating XN‐HPC count to date, 8‐14 and is the only study that analyzes both single‐ and multicenter data. The result of the correlation analysis is influenced by the sample size and the independence of the observations included.…”

“…An automated hematopoietic progenitor cell (HPC) count measurement using flow cytometry based on cell membrane permeability, size, and internal structural complexity, was developed by Sysmex (Kobe, Japan). The HPC count measured in Sysmex XN analyzer (Sysmex Corporation, Kobe, Japan, XN‐HPC) have shown a significantly improved correlation with flow cytometry CD34 + cell count 8‐15 compared to the previous XE analyzer‐based HPC count 16‐20 …”