The Isolation of Erythropoiesis Regulatory Factors by an Electrofractionation Technique Combined with Selective Membrane Permeability 1

Abstract

Summary

A urine concentrate from a patient with paroxysmal nocturnal hemoglobinuria contained four regulators of erythro-poiesis that could be isolated by an electro-fractionation technique combined with selective membrane permeability. An erythropoie-sis-stimulating factor (ESF) passed toward the anode through a membrane with a cutoff at a molecular weight of 30,000, but was retained by a membrane with a cutoff at 20,000, while another ESF was retained by a membrane with a cutoff at 50,000. An ESF-generating factor passed toward the cathode through a membrane with a cutoff at 50,000 but was retained by a membrane with a cutoff at 30,000.

An inhibitor of erythropoiesis (EIF) passed toward the cathode through a membrane with a cutoff at a mol wt of 30,000 but was retained by a membrane with a cutoff at 10,000. The EIF brought about maximal depression of erythropoiesis 6 days after the first of four daily injections, but erythropoiesis gradually returned to normal 3 days later, though the EIF injections were continued. The EIF appeared to be mostly lipid and about 7.5% protein.

The authors express their appreciation to members of the engineering departments at the Veterans Administration Hospitals in Augusta, GA and St. Louis, MO for their assistance in the construction of the electrofractionation apparatus used in this work.