Expression of human interleukin-17 in Pichia pastoris: purification and characterization

A Pichia pastoris expression clone has been developed to produce the human cytokine interleukin-17 (hIL-17). Characterization of purified recombinant hIL-17 made with this clone demonstrated that it shared many characteristics with hIL-17 produced in mammalian cells. The hIL-17 produced in Pichia had the correct N-terminus of natural mature hIL-17 and a glycosylation pattern similar to hIL-17 produced in mammalian cells; both Pichia and human cells add approximately 5 kDa of sugars via N-linked glycosylation and both express a mixture of the glycosylated and nonglycosylated forms. Gel filtration provides evidence that the Pichia produced hIL-17 exists as a dimer in solution. A combination of cation-exchange and gel-filtration chromatography yielded 3.5 mg of highly purified and biologically active hIL-17 from a 10-liter fermentation. These results show that P. pastoris is a useful system to produce recombinant hIL-17 in structure/function studies of this molecule.