[Preparation of recombinant cytokines. II. Effective method for isolation, purification and renaturation of human recombinant gamma-interferon].

An efficient method for the isolation, purification, and renaturation of human recombinant gamma-interferon from biomass of transformed E. coli cells was developed. It involves the extraction of the protein from the inclusion bodies, preliminary purification of the protein, and three stages of ion-exchange chromatography with an intermediate renaturation between the second and the third stages. A highly active (2 x 10(7) U/mg) recombinant protein of up to 99% purity (according to SDS-PAGE and HPLC) was obtained with a 30% overall yield.