Studies of the Renal Erythropoietic Factor Using a Hemagglutination-Inhibition System 1

Abstract

Summary

A hemagglutination-inhibition system utilizing gamma-globulins extracted from anti-ESF serum for the determination of erythropoietin (ESF) is reported. Use of this technique showed that the renal erythropoietic factor (REF) is different immunochemically from ESF. Small but detectable levels of ESF were found in normal serum and the incubation of REF with serum resulted in the generation of ESF. The small increases in red cell ⁵⁹Fe incorporation noted in assay mice treated with the REF alone is probably due to the endogenous production of the ESF.