Harvesting and enrichment of hematopoietic progenitor cells mobilized into the peripheral blood of normal donors by granulocyte-macrophage colony-stimulating factor (GM-CSF) or G-CSF: potential role in allogeneic marrow transplantation

Abstract

To explore the use of stem/progenitor cells from peripheral blood (PB) for allogeneic transplantation, we have studied the mobilization of progenitor cells in normal donors by growth factors. Normal subjects were administered either granulocyte-macrophage colony-stimulating factor (GM-CSF) at 10 micrograms/kg/d, or G-CSF at 10 micrograms/kg/d, or a combination of G- and GM-CSF at 5 micrograms/kg/d each, administered subcutaneously for 4 days, followed by leukapheresis on day 5. Mononuclear cells expressing CD34 (CD34+ cells) were selectively enriched by affinity labeling using Dynal paramagnetic microspheres (Baxter Isolex; Baxter Healthcare Corp, Santa Ana, CA). The baseline CD34+ cells in peripheral blood before mobilization was 0.07% +/- 0.05% (1.6 +/- 0.7/microL; n = 18). On the fifth day after stimulation (24 hours after the fourth dose), the CD34+ cells were 0.99% +/- 0.40% (61 +/- 14/microL) for the 8 subjects treated with G-CSF, 0.25% +/- 0.25% (3 +/- 3/microL, both P < .01 v G-CSF) for the 5 subjects administered GM-CSF, and for the 5 subjects treated with G- and GM-CSF, 0.65% +/- 0.28% (41 +/- 18/microL, P < .5 v GM-CSF). Parallel to this increase in CD34+ cells, clonogenic assays showed a corresponding increase in CFU- GM and BFU-E. The total number of CD34+ cells collected from the G-CSF group during a 3-hour apheresis was 119 +/- 65 x 10(6) and was not significantly different from that collected from the group treated with G- and GM-CSF (101 +/- 35 x 10(6) cells), but both were greater than that from the group treated with GM-CSF (12.6 +/- 6.1 x 10(6); P < .01 for both comparisons). Analysis of the CD34+ subsets showed that a significantly higher percentage of cells with the CD34+/CD38- phenotype is found after mobilization with G- and GM-CSF. In the G-CSF group, immunomagnetic selection of CD34+ cells permitted the enrichment of the CD34+ cells in the apheresis product to 81% +/- 11%, with a 48% +/- 12% yield and to a purity of 77% +/- 21% with a 51% +/- 15% recovery in the G- and GM-CSF group. T cells were depleted from a mean of 4.5 +/- 2.0 x 10(9) to 4.3 +/- 5.2 x 10(6) after selection, representing 99.9% depletion. We conclude that it is feasible to collect sufficient numbers of PB progenitor cells from normal donors with one to two leukapheresis procedures for allogeneic transplantation.(ABSTRACT TRUNCATED AT 250 WORDS)

Purging Peripheral Blood Progenitor Cell Grafts from Lymphoma Cells: Quantitative Comparison of Immunomagnetic CD34 + Selection Systems

“…Thus, ex vivo elimination of lymphoma cells from stem cell grafts seems desirable to further improve the long-term results of transplant. As PBPCs have replaced BM as the principal source of stem cells [4,6], CD34 + selection appears to be a particularly attractive method for ex vivo purging of PBPC grafts from lymphoma cells, since this method can easily be applied to the large cell numbers present in leukapheresis products and has been shown to be associated with a high efficacy when used for depletion of T cells or tumor cells from PBPC grafts [11,12,18,22,23].…”

The composition of leukapheresis products impacts on the hematopoietic recovery after autologous transplantation independently of the mobilization regimen

“…Until now, several studies have comparatively analyzed the effect that G-CSF or GM-CSF administered alone or in combination with CCP has on the mobilization into PB of the more immature CD34+ HPCs, identified as CD34+ CD38-cells and/or CD34+ HLA-DRcells. 20,[38][39][40] In contrast, these studies have not included a comprehensive comparison with SCF plus G-CSF plus CCP. Our results show that the use SCF plus G-CSF plus CCP was associated with significantly higher numbers of all the different CD34+ cell subsets analyzed compared to both G-CSF-and G-CSF plus CCP-based mobilization protocols.…”

The Use of Mobilized Peripheral Blood Stem Cells from Normal Donors for Allografting

“…To assess the effects of rHuG-CSF (12 µg/kg/d) on the peripheralization of hematopoietic progenitor cells and lymphoid subsets, we studied a cohort of 41 normal blood stem 10 Mobilized Peripheral Blood Stem Cells for Allografting PBSCs may eventually replace, at least in part, BM as the preferred source of stem cells for both autoand allotransplantation.…”