Patent ID: 8729244

Claim:
A method for purifying factor B, the method comprising: (i) obtaining a blood plasma fraction containing factor B; (ii) subjecting the fraction obtained in step (i) to affinity chromatography on a sepharose gel onto which heparin is grafted and collecting a factor B-enriched fraction; (iii) subjecting the factor B-enriched fraction obtained in step (ii) to cation exchange chromatography on SP-Sepharose, collecting a fraction further enriched in factor B, and treating the fraction further enriched in factor B with solvent and detergent; (iv) subjecting the treated fraction further enriched in factor B obtained in step (iii) to anion exchange chromatography on Q-Sepharose; and (v) eluting the factor B, wherein the blood plasma fraction containing factor B is obtained from the supernatant of a blood plasma cryoprecipitate optionally mixed with a plasma fraction not retained on an anion exchange chromatography, or a plasma fraction not retained on an anion exchange chromatography, and the blood plasma fraction containing factor B is adjusted to a pH of 6 prior to step (ii).