Methods for the preparation of purified granulopoiesis-inhibiting factor (chalone)

This paper describes in some detail methods which may be useful for the preparation of chalone-like granulopoietic inhibitor(s). Details are given for a) preparation of crude starting material from various sources, b) primary extraction and crude fractionation techniques, c) gel chromatography, d) anion exchange chromatography, and e) thiol-binding chromatography. Possibilities for the chromatographic use of marker substances are discussed and methods for obtaining the factor in radioactively labeled form are given. Some of the stability problems encountered during working and storage of granulopoiesis-inhibiting factor (GIF) are discussed. The purpose of this paper is to provide simple chemical techniques for the purification of GIF for investigators with mainly biological interests.