Retrovirally-produced erythropoietin effectively induces differentiation and proliferation of J2E erythroid cells

The J2E erythroid cell line terminally differentiates in response to recombinant human erythropoietin (rHu-epo). Here we demonstrate that retrovirally produced monkey erythropoietin (Zen-epo) is also capable of inducing the final maturation steps of J2E cells in a dose-dependant manner. The hormone committed J2E cells to a pathway of accelerated proliferation, haemoglobin synthesis and morphological changes including enucleation. However, only 6 h exposure to Zen-epo was required to initiate maximum haemoglobin synthesis 72 h later. Significantly, the synthesis of haemoglobin was achieved by concomitantly activating globin production, haem synthesis and iron uptake. Methylcellulose assays revealed that the vast majority of clonogenic cells were able to respond to Zen-epo. These data show that retrovirally manufactured erythropoietin is an effective stimulus for the erythropoietic development of J2E cells in vitro.