Abstract
The effects of hematopoietic growth factors on in vitro human megakaryocytopoiesis were studied using a serum-depleted culture system. Both recombinant interleukin-3 (rIL-3) and recombinant granulocyte-macrophage colony-stimulating factor (rGM-CSF) increased megakaryocyte (MK) colony formation (P < .01) above that observed in baseline cultures. Recombinant interleukin-4 (rIL-4) and interleukin 1α (rIL-1α) failed either to promote MK colony formation alone or to increase rIL-3 or rGM-CSF promoted colony formation. Recombinant erythropoietin (rEpo) and purified thrombocytopoiesis-stimulating factor (TSF) did not increase (P > .05) MK colony formation when added alone but synergized with rIL-1α, leading to a twofold increase in MK colony formation. Such a synergistic relationship was not observed between rIL-4 and rEpo. In addition, TSF enhanced the ability of rIL-3 but not rGM-CSF to promote MK colony formation. Addition of rEpo to optimal or suboptimal concentrations of rGM-CSF or suboptimal concentrations of rIL-3 resulted in a significant increase (P < .05) in the total number of MK-containing colonies, due to the appearance of multilineage colonies containing MKs. The addition of rEpo to optimal concentrations of rIL-3 resulted in increased numbers of multilineage colonies containing MKs; however, the number of total MK-containing colonies was not significantly increased when compared to assays containing rIL-3 alone. By contrast, transforming growth factor-β (TFG-β) inhibited both rIL-3, and rGM-CSF promoted MK colony formation, with optimal inhibition resulting in a 35%-45% reduction of MK colony formation. These data suggest that a number of growth factors can regulate in vitro human megakaryocytopoiesis by either promoting or inhibiting MK colony formation.
Original language | English |
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Pages (from-to) | 671-677 |
Number of pages | 7 |
Journal | Blood |
Volume | 73 |
Issue number | 3 |
DOIs | |
State | Published - 1989 |
Externally published | Yes |