The biochemistry of erythropoietin: an approach to its mode of action.

The elucidation of the mechanism of action of erythropoietin depends upon a detailed assessment of its effects at the molecular level. We have now begun to examine the effects of human erythropoietin and other inducers on clonal lines of Rauscher murine erythroleukemia cells. Over 100 clonal lines have been examined by assessing the hemglobinization of colonies grown in plasma clot culture in response to erythropoietin and dimethylsulfoxide. Many of the clones respond to both inducers. However, some clones respond only to erythropoietin. The cells also differentiate in suspension culture, exhibiting striking morphological changes characteristic of erythroid development. This system should serve as an excellent model for the study of control mechanisms in erythropoiesis.