Objective: To explore the differences between recombinant human granulocyte colony-stimulating factor (rhG-CSF) primed and non-primed peripheral blood stem cell harvests.
Methods: The constituents of the harvests including CD(3)(+), CD(4)(+), CD(8)(+), CD(19)(+), CD(14)(+), CD(34)(+) and CD(56)(+) cells, T cell subsets, dendritic cells (DCs) and their subsets, the costimulating molecular expression on monocyte and B lymphocyte and the quantities of IL-4 and IFNgamma secreted by CD(4)(+) T cells were analyzed with multicolor flow cytometry T cells proliferation was studied using MTT techniques.
Results: There was statistically significant difference of the proportion of CD(3)(+), CD(4)(+), CD(34)(+), CD(14)(+) cells between A group (rhG-CSF primed peripheral blood stem cell harvests) and B group (non-primed peripheral lymphocyte harvests). The percentages of DCs and their subsets in A group were higher than those in B group, especially the percentage of DC2 was much higher (P = 0.000). The proportion of IL-4 producing CD(4)(+) T cells (Th2 cell) and the ratio of IL-4/IFNgamma (IL-4 producing CD(4)(+) T cells/IFNgamma producing CD(4)(+) T cells) in A group was significantly higher than those B group (P = 0.044, 0.012). Furthermore, the T cell proliferation ability in A group was lower than that in B group.
Conclusions: rhG-CSF primed peripheral blood stem cell harvests contained more CD(34)(+) cells, CD(14)(+) cells, Th2 cell and type II cytokines than non-primed peripheral lymphocyte harvests. The differences of immunologic composition and function between A group and B group may help to provide a biological explanation for the lower occurrence of acute graft versus host disease following peripheral blood stem cell infusion than following donor lymphocyte infusion.