Synergism of Hemopoietic Growth Factors on Endothelial Cell Proliferation

Endothelial cells, which are nonhemopoietic cells, express and/or produce most of the known hemopoietic receptors and cytokines. The biological role of these factors, and their respective receptors, on endothelial cells is still unknown. In this study, the authors assessed the effect of different hemopoietic growth factors, ie, interleukin-3 (IL-3), erythropoietin (EPO), macrophage-colony stimulating factor (M-CSF), granulocyte-colony stimulating factor (G-CSF), granulocyte macrophage-colony stimulating factor (GM-CSF), singly or in conjunction with others, on proliferation and chemotaxis of human umbilical vein endothelial cells (HUVECs). They found growth stimulatory activity with IL-3, EPO, and GM-CSF and potent synergism between EPO and IL-3, less with IL-3 and GM-CSF, and none with EPO and either GM-CSF or G-CSF. All the singly tested hemopoietic growth factors stimulated the migration of HUVECs, but in conjunction with other factors, they did not show any additive or synergistic effect.