[Using process of refolding the protein to obtain recombinant human interleukin-1 receptor antagonist]

Shugang Li1, Xiaoyan Deng, Hong Zhao

  • 1College of Bioengineering of Chongqing University, Chongqing 400044, China.

Recombinant human interleukin-1 receptor antagonist was expressed in E. coli as an insoluble inclusion body. The inclusion body was dissolved in the 8 M urea and then the solution was diluted untill the concentration of urea became 2 M. By ion exchange chromatography the protein in the solution of 2 M urea was refolded and purified. At last the purity of product is more than 95% and its bioactivity is more than 1 x 10(5) IU/mg while it has little endotoxin. Western-Blotting also indicates that recombinant protein can react with antibodies against anti-hIL-1ra.

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