CD14+ cells in granulocyte colony-stimulating factor (G-CSF)-mobilized peripheral blood mononuclear cells induce secretion of interleukin-6 and G-CSF by marrow stroma.

Publication Type:

Journal Article

Source:

Blood, Volume 87, Issue 2, p.574-80 (1996)

Keywords:

Antigens, CD14, Bone Marrow, Bone Marrow Cells, Cell Line, Transformed, Cell Separation, Cells, Cultured, Coculture Techniques, Connective Tissue, Culture Media, Conditioned, Granulocyte Colony-Stimulating Factor, Hematopoietic Stem Cells, Humans, Interleukin-1, Interleukin-6, Leukapheresis, Recombinant Proteins

Abstract:

The ability of granulocyte colony-stimulating factor (G-CSF)-mobilized peripheral blood mononuclear cells (G-PBMCs) to induce secretion of cytokines in primary long-term marrow cultures (LTC) or in the human marrow stromal cell line HS23 was compared with that of marrow mononuclear cells. Equal numbers of G-PBMCs or marrow mononuclear cells were added to stromal cultures, supernatants were harvested at day 4 and levels of interleukin-1 alpha (IL-1 alpha), IL-1 beta, IL-2, IL-6, G-CSF, and tumor necrosis factor alpha (TNF alpha) were determined. G-PBMCs induced 21.4-fold higher levels of IL-6 and 12.5-fold higher levels of G-CSF in LTC cocultures compared with marrow mononuclear cells and induced 20.6-fold more IL-6 and 6.3-fold more G-CSF when added to HS23 cells. Experiments using sorted populations of CD20+, CD3+, and CD14+ cells showed that CD14+ cells within G-PBMCs were responsible for triggering the production of IL-6 and G-CSF. The effect did not require cell-cell contact and was inhibited when neutralizing antibodies to IL-1 alpha and IL-1 beta were used in combination. In these experiments, the greater stimulating ability of G-PBMCs is most likely attributable to the greater number of CD14+ cells in G-PBMCs (26.1+% +/- 2.3%) compared with marrow (2.5% +/- 0.8%), because equal numbers of CD14+ cells sorted from marrow and G-PBMCs showed comparable ability to induce IL-6 and G-CSF when placed directly on stromal cells.