SYNERGISM OF HEMATOPOIETIC GROWTH-FACTORS ON ENDOTHELIAL-CELL PROLIFERATION

Endothelial cells, which are nonhemopoietic cells, express and/or prod uce most of the known hemopoietic receptors and cytokines. The biologi cal role of these factors, and their respective receptors, on endothel ial cells is still unknown. In this study, the authors assessed the ef fect 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 othe rs, on proliferation and chemotaxis of human umbilical vein endothelia l cells (HUVECs). They found growth stimulatory activity with IL-3, EP O, and CM-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 si ngly tested hemopoietic growth factors stimulated the migration of HUV ECs, but in conjunction with other factors, they did not show any addi tive or synergistic effect.