Expression of Human Serum Albumin-Interleukin-2 Fusion Protein in Chinese Hamster Ovary Cells

Abstract:

Interleukin-2（IL-2） plays an important role in immune response and is wildly used as therapeutic protein to treat diseases，such as cancer，hepatitis and immunodeficiency. In this study，the pMH3 plasmid containing fusion protein of human serum albumin and IL-2 was constructed and then transfected to Chinese hamster ovary（CHO） cells by electroporation. CHO cells stably expressing the target protein were selected by neo gene in pMH3 plasmid and determined by Dot-blot during 96-plate culture. The titer of HSA-IL-2 was 2.26 mg/L in the 24-plate culture. Reverse transcription PCR and western blot showed that the gene encoding HSA-IL-2 was integrated to genome of recombinant CHO cells and the secreted fusion protein was detected by antibody to be HSA and IL-2. The biological activity of fusion protein was analyzed by IL-2 dependent CTLL-2 cells，and the result showed that the recombinant protein possessed a high activity. In conclusion，the recombinant CHO cells producing biological fusion protein of HSA-IL-2 were successful established.