Recombinant human interleukin-6 accelerates in-vitro megakaryocytopoiesis and platelet recovery post autologous peripheral blood stem cell transplantation.

Prolonged thrombocytopenia complicated by bleeding episodes represent a major problem following autologous bone marrow transplantation (ABMT). Recombinant human interleukin-6 (rhIL-6) has been shown to be a maturation factor for both mouse and human megakaryocytes. We administered rhIL-6 to a 43 year old woman who developed marked resistant and prolonged thrombocytopenia with bleeding episodes following autologous peripheral blood stem cell transplantation (APBSCT). Twenty days after the initiation of rhIL-6 therapy, the number of megakaryocyte (MK) progenitors (CFU-MK and BFU-MK) cultured from the peripheral blood increased followed by a moderate increase in the number of bone marrow megakaryocytes. The platelet count increased and the bleeding episodes disappeared. Although spontaneous platelet recovery cannot be ruled out in this case it seems that rhIL-6 may be an important thrombopoietic factor for severe thrombocytopenia following APBSCT.