the present invention is drawn to mutant interleukin 6 , which has the amino acid arginine in position 176 , replacing serine in position 176 with wild - type interleukin 6 . the mutant interleukin 6 of the present invention has greater biological activity than the wild - type protein . the present invention is further drawn to methods of making mutant interleukin 6 , having arginine at position 176 and methods of using the same .