Use of Zetaprep Cartridge for the Purification of Human Recombinant Interleukin 1β

Zetaprep mass ion-exchange media represent a rapid and efficient chromatographic tool in the separation of proteins, in place of the conventional agarose or cellulose-based gels. We adopted this method, combined with classical steps, to purify to homogeneity human recombinant interleukin 1β (IL-1β) produced from E. Coli and from S. cerevisiae. An anion exchanger QAE-ZetaPrep was used to achieve a rapid partial purification of both proteins. The IL-1β purification was completed by gel permeation chromatography on Sephadex G-50. When the protein was produced from yeast, an intermediate chromatographic step on a hydroxylapatite column was also necessary. The isolated proteins proved to be homogeneous by electrophoresis and amino acid analysis. The biological activity of IL-1β produced by E. coli is comparable to that of the natural protein, while the protein produced by yeast showed very low specific activity.