Disubstituted pegylated interleukin 2, preparation method therefor and use thereof

A PEGylated interleukin 2, wherein a preparation method for the PEGylated interleukin 2 comprises the steps of:

• (1) reacting PEG with IL-2 to obtain a crude product of a PEGylated interleukin 2;
• (2) performing gel chromatography filtration to remove free interleukin 2 from the crude product;
• (3) performing affinity chromatography on a product in the step (2) by means of an α receptor column, and collecting a flow-through peak component and an elution peak component;
• and
• (4) performing ion exchange separation on one or two of the flow-through peak component and the elution peak component in the step (3), and collecting to obtain components of the PEGylated interleukin 2.

A preparation method for a disubstituted PEGylated interleukin 2, comprising the steps of:

• (1) reacting PEG with IL-2 to obtain a crude product of a PEGylated interleukin 2;
• (2) performing gel chromatography filtration to remove free interleukin 2 from the crude product;
• (3) performing affinity chromatography on a product in the step (2) by means of an α receptor column, and collecting a flow-through peak component and an elution peak component;
• and
• (4) performing ion exchange separation on one or two of the flow-through peak component and the elution peak component in the step (3), and collecting to obtain components of the disubstituted PEGylated interleukin 2.