Expression and purification of IFNβ-HSA fusion protein in Pichia pastoris

Abstract:

In order to obtain enough fusion protein for developing preclinical studies of IFNb-HAS, we screened Pichia pastoris transformants expressing high-level protein by immunology method. The yield of IFNβ-HSA was about 500 mg/L by fed-batch fermentation. The purity of IFNβ-HSA reached 96% through the steps of ultrafiltration, Blue Sepharose FF, Ni2+-IMAC and DEAE Sepharose FF. Analysis of Western blotting showed that IFNβ-HSA had the antigenicity of IFNβ and HSA. The specific activity was about 1.96×107 IU/mg by standard survival activity test on WISH cells challenged with VSV virus. This study provided a method to produce IFNβ-HSA.