Expression and Purification of Human Interferon-ω in Yeast Pichia pastoris

IFN-ω is a kind of interferon molecules,which has similar function but different antigenicity to IFN-α.It can inhibit virus replication like IFN-α,IFN-γ and tumor necrosis factor alpha.5 L fermenter was used to ferment and interferon-ω was expressed.Then,the glycosylated interferon-ω was purified by a procedure stepped by ultrafiltration and gradient elution SP chromatography column.Its molecular weight and N amino acid sequence were analyzed by MALDI TOF-TOF MS and the N protein sequence analyzer,respectively.In addition,IFN-ω activity was determined by cell changes suppression method.The results showed that IFN-ω expression level reached to highest in induced 48 h.The glycosylated and unglycosylated IFN-ω could be separated by SP gradient elution completely.The glycosylated IFN-ω showed a series of continuous peaks by mass spectrometry,which is the characteristic peak of glycosyl protein.The antiviral activity of the purified glycosylated IFN-ω was 1.46×108 U/mL.