Quantitative determination of human plasma erythropoietin using embryonic mouse liver erythroblasts

An in vitro bioassay for the quantitative detection of erythropoietin (Ep) in human plasma is described. The method is based on the increased 3H-uridine incorporation into 12-day embryonic mouse liver erythroblasts due to Ep. It was found that 11 out of 12 anaemic patients showed high plasma Ep level, while 7 out of 8 patients suffering from polycythaemia revealed low Ep values. In 4 out of 8 patients with chronic renal failure the Ep level was within the normal range, whereas in the remaining 4 it was higher than normal. The relative simplicity of the method and the reproducibility of the results make it useful even in the routine laboratory.