In vivo effect of human erythroid-potentiating activity on hematopoiesis in mice

Endotoxin-free purified recombinant human erythroid-potentiating activity (EPA) was administered to normal and bled mice. In anemic ICR mice EPA treatment led to a significant increase in the number of reticulocytes in the peripheral blood and erythroid precursors in the spleen. Stimulation of CFU-E and BFU-E in the spleen was also observed in C3H/HEJ mice, which excluded the possibility of endotoxin effect. Unchanged, 51Cr-tagged red cell survival and lack of radioactivity in the stool or urine suggests that the EPA stimulation of erythropoiesis was not due to hemolysis or bleeding. Thus, EPA has an effect on erythropoiesis in anemic mice in vivo.