THE SYNERGISTIC EFFECT OF THROMBOPOIETIN IN ERYTHROPOIESIS WITH ERYTHROPOIETIN AND/OR IL-3 AND MYELOPOIESIS WITH G-CSF OR IL-3 FROM UMBILICAL CORD BLOOD CELLS OF PREMATURE NEONATES

The authors sought to determine whether recombinant human thrombopoietin (TPO) acts synergistically with other cytokine(s) on burst-forming unit-erythroid (BFU-E)-derived and colony-forming unit-granulocyte/macrophage (CFU-GM)-derived colony formations from cord blood of premature neonates. Cord blood nonadherent mononuclear cells (MNC) from normal premature neonates were cultured in a methylcellulose system. When cultured with 1 2 10 4 MNC/mL, erythropoietin (EPO) 2 U/mL, interleukin-3 (IL-3) 50 ng/mL, and/or TPO 100 ng/mL, the addition of TPO to EPO gave rise to more BFU-E-derived colonies ( p = .000). The addition of TPO to EPO + IL-3 gave rise to more BFU-E-derived colonies ( p = .002) also. TPO synergizes erythropoiesis from cord blood of premature neonates. Likewise, the addition of TPO to G-CSF gave rise to more CFU-GM-derived colonies ( p = .000) also. TPO synergizes myelopoiesis from cord blood of premature neonates. Thus, TPO has synergistic effects on both erythropoiesis and myelopoiesis from cord blood of premature neonates.