Control Peptide for 029815. Interleukin-18 (IL-18), an 18kD cytokine, is a single, non-glycosylated polypeptide chain containing 157aa. IL-18 was previously known as interferon-gamma inducing factor (IGIF). This pleiotropic cytokine is produced by monocyte/macrophage cells. Like IL-12, IL-18 plays an important role in cell-mediated immune responses. Source: Synthetic peptide corresponding to aa41 from human IL-18. Applications: Suitable for use in ELISA and Antibody Blocking.