IN-VITRO AND IN-VIVO EFFECTS OF RECOMBINANT-HUMAN-ERYTHROPOIETIN PLUSRECOMBINANT HUMAN G-CSF ON HUMAN HEMATOPOIETIC PROGENITOR CELLS

We tested in vitro the effect of recombinant human erythropoietin (rhE PO) plus recombinant human G-CSF (rhG-CSF) on purified human CD34(+) h aemopoietic progenitors (HP) and in vivo in patients who had undergone anti-cancer chemotherapy for advanced ovarian cancer. In this prelimi nary experience we found that, in vitro, rhEPO potentiates the effect of rhG-CSF on HP growth and differentiation toward the granulocyte-mac rophage lineage. rhEPO plus rhG-CSF produced in vitro a proliferative stimulus of HP which represents 26% of the maximum stimulation obtaine d using IL-1, IL-3, IL-6, G-CSF, GM-CSF and stem cell factor in combin ation. In the patients treated with rhEPO plus rhG-CSF after chemother apy, we observed a favourable trend for platelet and neutrophil recove ries compared with a control group treated with rhG-CSF alone and a si gnificantly higher haematocrit nadir was observed in the rhEPO plus rh G-CSF series. In the patients treated with rhEPO plus rhG-CSF we obser ved a significant increase of circulating colony-forming unit granuloc yte-macrophage (CFU-GM) and burst forming unit-erythroid (BFU-e) compa red with the rhG-CSF series. Our results, in vitro and in vivo, encour age the in vivo use of rhEPO plus rhG-CSF to improve blood cell recove ries of patients who have undergone conventional or high-dose chemothe rapy. Moreover, rhEPO plus rhG-CSF was demonstrated to be a good HP mo bilising treatment for blood stem cell collection after chemotherapy.