Determination of peripheral blood stem cells by the Sysmex SE-9500

Abstract

The Sysmex SE-9500 automated haematology analyser provides an estimate of immature cells, referred to as 'haematopoietic progenitor cells' (HPC). The aim of this study was to evaluate the reliability and usefulness of the SE-9500 HPC parameter as compared with the CD34 + cell count and to determine whether the HPC count was of value in predicting the optimal harvesting time for peripheral blood stem cells (PBSC). Studies were performed on 112 samples from 21 patients with haematological malignancies and 13 healthy donors undergoing progenitor cell mobilisation. Coefficients of variation for the HPC count were 30%, 23.8%, 12.4% and 8.3% respectively for samples with low (4 x 106/l), medium (13 x 106/l), high (250 x 106/l) and very high (2413 x 106/l) counts. There was good linearity for HPC measurement in both peripheral blood (PB) and purified CD34 + cell suspensions (r > 0.995), and no detectable carryover was observed. There was an acceptable correlation between HPC and CD34 + cell counts for PB samples (r=0.669) and for CD34 + cell suspensions (r=0.859). Analysis of purified CD34 + cells using the SE-9500 HPC mode revealed that they appear both in the blast cell area and the immature granulocyte area of the analyser cell display. Quantitation of CD34 + cells and HPC during PBSC mobilisation showed good agreement between these parameters with regard to the optimal time for PBSC harvesting. These findings suggest that HPC counting with the Sysmex SE-9500 may be clinically useful for optimising the timing of PBSC collection.

Correlations between hematopoietic progenitor cell counts as measured by Sysmex and CD34+ cell harvest yields following mobilization with different regimens

“…On the other hand, HPC counts were about fourfold lower than CD34+ cell counts in CD34 selected apheresis preparations; these results were comparable to those recently observed by Peng et al (Peng et al 2001). The precise nature of the progenitors measured in the HPC channel is unclear.…”

Novel and rapid enumeration method of peripheral blood stem cells using automated hematology analyzer

“…In this study, we demonstrated that there was a good correlation between the numbers of HPCs and CD34 + cells in samples from not only the PB but also apheresis products. The correlation coefficient was much closer to 1.0 with this novel XN‐determined HPC count than with the previous SE/XE‐determined HPC count . These results suggested that the number of CD34 + cells in the final products could be predicted from the HPC count in the final products.…”

Clinical Usefulness of the Hematopoietic Progenitor Cell Counts in Predicting the Optimal Timing of Peripheral Blood Stem Cell Harvest

“…Clinical implications for peripheral blood progenitor cells collection where the decision to commence apheresis is modified by peripheral blood WBC, MNC, or HPC ture forms to be counted (19,26,27). Previous studies reported a strong correlation between PB HPC and PB CD34+ cell counts (25,28), and we have reported a strong correlation between HPC enumerated by Sysmex SE-9000 and CD34+ cells in the leukapheresis products from data on 32 patients (20). This strong correlation led us to investigate the clinical usefulness of HPC as a screening test to decide when to commence PBPC collection.…”