Expression and characterization of an EGF-IL-18 fusion protein for targeting (therapy) in insect cells / 中国免疫学杂志

ABSTRACT

Objective:To express and purify a new fusion protein harboring human epidermal growth factor receptor(EGFR) binding domain and Interleukin-18(IL-18), as well as preliminary assay biological activity of recombinant proteins.Methods:Fusion protein was expressed in insect cells Spodoptera frugiperda cell (Sf9) by using Bac-to-Bac system, and an abbreviation purification procedure was used to purify fusion protein. IFN-?induction assay and EGF Receptor competitive test was used to determine fusion protein's biological activity.Results:SDS-PAGE and western blot assay showed that purified EGF-IL-18 fusion protein had high purity in 20 kD as expected and had the same antigenic specificity as human IL-18. IFN-?induction assay and EGF Receptor competitive test showed that fusion protein induced production of IFN-?in human PBMC and bound with tumor cells.Conclusion:EGF-IL-18 fusion protein has been successfully expressed and purified in insect cells and shows potential to apply in targeting therapy for tumor.