Megakaryopoiesis in vitro in myelodysplastic syndromes and acute myeloid leukaemia: effect of pegylated recombinant human megakaryocyte growth and development factor in combination with other growth factors

Pegylated recombinant human megakaryocyte growth and development factor (PE G-rHuMGDF) can stimulate megakaryopoiesis in vitro in some myelodysplastic syndrome (MDS) and acute myeloid leukaemia (AML) patients. We assessed PEG- rHuMGDF combined with granulocyte colony-stimulating factor (G-CSF), granul ocyte-macrophage CSF (GM-CSF), interleukin 3 (IL-3), IL6, stem cell factor (SCF) or erythropoietin in 40 MDS, 33 AML and 16 normal bone marrow samples , CD61-positive cells in suspension cultures increased with PEG-rHuMGDF alo ne in 20/25 RA + RAS, 11/14 RAEB + RAEBt and 29/33 AML cases. Further incre ases when IL-3 and/or SCF were added to PEG-rHuMGDF occurred in 14/20 RA RAS. 8/13 RAEB + RAEBt and 18/26 AML cases. CFU-Mlr growth was poor overall , but could be enhanced by PEG-rHuMGDF combinations in some patients, Stimu lation of megakaryopoiesis by PEG-rHuMGDF can be augmented by IL-3 and SCF in many MDS and AML patients.