Identification of an erythropoietin-sensitive cell line

The murine lymphoblastic cell line DA-1 has been characterized as dependent upon both interleukin-3 (IL-3, multicolony-stimulating factor [multi-CSF]) and granulocyte-macrophage colony-stimulating factor (GM- CSF) for survival and growth. Here we demonstrate that it is responsive to a third hematopoietic factor, the erythroid-specific hormone, erythropoietin (Epo). DA-1 cells are stimulated to proliferate by partly purified natural murine and human Epo, and pure recombinant human Epo. Antibody to Epo specifically blocks Epo-stimulated growth. Maximal growth stimulated by Epo and GM-CSF is similar, and considerably less than that stimulated by multi-CSF. Proliferation stimulated by Epo and GM-CSF is transient, decreasing within 24 to 48 hours of exposure. However, Epo acts cooperatively with GM-CSF to sustain proliferation. With or without GM-CSF, no obvious erythroid differentiation of DA-1 cells occurs after exposure to Epo for up to 72 hours. This is the first report of a growth factor-dependent cell line also responsive to Epo for survival and growth. The availability of this cell line model should greatly facilitate biochemical analysis of the mechanism of Epo growth-stimulating action.