IL-1α and IL-1β have nearly identical biological activity in that they induce adhesion molecule expression on epithelial cells, control fever induction, and play a role in arthritis and septic shock. Signaling activated by the IL-1R1 promotes these activities through a MYD88 signaling pathway similar to those associated with Toll receptors. Recombinant Human Interleukin-1-beta, produced in E.coli, is a non-glycosylated, polypeptide chain that contains 154 amino acids and has a molecular mass of 17.5 kDa. rHu IL-1ß is purified by proprietary chromotographic technique.