Animal-free Recombinant Human IL-27 is expressed in human 293 cells as a non-covalently bonded heterodimer cytokine composed of IL27p28 (25 kDa) and glycosylated EB13 (30 kDa). Production in human 293 cells uses a serum-free, chemically defined media and offers authentic glycosylation. Cytokines produced in non-human expression systems may have an artificial linker, a tag, and/or not human-like posttranslational modifications.