Hematopoietic stem cells from poor and good mobilizers are qualitatively equivalent

Abstract

Background Marrow damage from chemo- and radiation therapies has been suggested to affect quality and quantity of Hematopoietic stem cell (HSC) products. We tested the hypothesis that CD34+ cells (HSC) from low mobilizers are qualitatively inferior to HSC from high mobilizers. Materials and Methods HSC quality was defined by proportion of primitive HSC subsets (CD34+CD38−, CD34+HLA-DR− and CD34+ in G0 stage of cell cycle), the proportion of HSCs that express CXCR4 and CD26 homing proteins and days, to neutrophil and platelet engraftments post transplant. HSC content and CD34 subsets analyses were performed using flow cytometry following ISHAGE protocol. We evaluated the HSC quantity and quality of 139 autologous filgrastim mobilized HSC products. Patients were categorized into low, moderate and high mobilizers if their total HSC collection was <3 ×106/kg, ≥3 ×106/kg and <5 ×106/kg, and ≥5 × 106/Kg respectively. Results The median number of primitive CD34 subsets increases with increasing HSC numbers and this association was statistically significant (p = 0.001). However, when the ratios of the primitive CD34 subsets to total HSC counts were compared among the mobilization groups, the ratios were not significantly different. Co-expression of neither CD26 nor CXCR4 with CD34 antigen correlated with HSC mobilization. Evaluation of days to neutrophil engraftment among the mobilization groups did not show a statistically significant difference (p = 0.1). However, days to platelet engraftment among the mobilization groups was statistically significantly different (p = 0.05). Conclusion The quality of HSCs from low mobilizers was comparable to HSCs from high mobilizers.

Influence of plerixafor on the mobilization of CD34+ cell subpopulations and lymphocyte subtypes

“…11 With regard to frequencies of CD341CD38-stem cell subsets our findings are in line with a recently published study analyzing grafts from 139 NHL patients after mobilization with G-CSF alone. 31 This study shows that stem cell grafts contained a relatively high amount of primitive CD341CD38-cells (52%-55%). These findings are comparable to our results detected in the G group (mean percentage of MPPs, 49.2%).…”

Comparison of biosimilar filgrastim with originator filgrastim for peripheral blood stem cell mobilization and engraftment in patients with multiple myeloma undergoing autologous stem cell transplantation

“…Jiang and colleagues have reported that mobilization capacity affects time to PLT engraftment and is significantly shorter in high mobilizers (CD34+ yield > 5 × 10 6 /kg at first leukapheresis) compared to low mobilizers (CD34+ cell yield < 3 × 10 6 /kg at first leukapheresis). Contrary to these findings, despite fewer numbers of low mobilizers in the Nivestim group compared to the Neupogen group and similar numbers of high mobilizers, a delay in time to PLT engraftment in the Nivestim group was observed.…”

CD34+ cell subclasses and lymphocyte subsets in blood grafts collected after various mobilization methods in myeloma patients

“…A critical point is whether the grafts collected from poor mobilizers are intrinsically different than those collected from standard mobilizers except for poorer yield of CD34+ cells. A recent study suggests that quality of hematopoietic stem cells is comparable in good mobilizers compared to poor mobilizers 33 . Apparently, this issue can be answered only through a randomized mobilization study.…”