Eosinophil derived neurotoxin (EDN) levels in commercial human urinary preparations of glycoprotein hormones

Eosinophil derived neurotoxin (EDN) is a ubiquitous human ribonuclease, occ urring not only in eosinophils, but also in many tissues and body fluids. I t may be a contaminant of commercial human urinary preparations of chorioni c gonadotropin (hCG) and other glycoprotein hormones. Here we describe the use of a fast commercial assay to quantify this contaminant and demonstrate that the content varies much between different commercial glycoprotein hor mone preparations. As this ribonuclease may have a cytotoxic activity on ce rtain cells, it is useful to be able to determine its quantity in a fast an d reliable way in these preparations. (C) 1999 Elsevier Science Ireland Ltd . All rights reserved.