Preparation of an Infectious Mononucleosis Receptor from Sheep Erythrocyte Stroma

Abstract

A method is described for the isolation and purification of infectious mononucleosis receptor (IMR) in high yield from sheep erythrocyte stroma. The procedure involves extraction of the stroma successively with boiling acetone, 100, 75 and 50% ethanol which removes approximately 40% non-infectious-mononucleosis-active material. Subsequent phenol/buffered saline extraction of the residue from the organic extraction yields a highly active IMR preparation in the aqueous phases. This material was further purified by ethanol precipitation and gel filtration chromatography. The yield was 0.2% of the stroma. Approximately 0.1 μg/ml of the purified IMR inhibits 4 agglutinating units of infectious mononucleosis (IM) serum. The material is a glycoprotein containing N-acetyl- and N-glycolylneuraminic acids, hexose, hexosamine and approximately 46% protein. It gives one band in immunoelectrophoresis with IM serum and loses IM specificity upon treatment with neuraminidase.