Method for the Purification of G-CSF

Abstract

The present invention relates to a method for obtaining recombinant granulocyte-colony stimulating factor (G-CSF), comprising at least one cation exchange chromatography and at least one hydrophobic interaction chromatography, wherein said two chromatographic steps are immediately consecutive in optional order. In particular, the present invention relates to a method for purifying G-CSF from a mixture of G-CSF and other proteins, comprising two cation exchange chromatography steps which are conducted before and after a hydrophobic interaction chromatography, respectively.

1 . A method of purifying a protein expressed in a denatured insoluble intracellular form in a non-mammalian expression system, comprising:
 (a) solubilizing the protein in a solubilization solution comprising a solubilizing agent;   (b) forming a refold solution comprising the solubilization solution and a refold buffer, the refold buffer comprising a refolding agent;   (c) loading the refold solution to a chromatography matrix under conditions for the protein to bind to the matrix;   (d) washing the chromatography matrix; and   (e) eluting the protein from the chromatography matrix.