Description: Cytokine that binds to TNFRSF13B/TACI and TNFRSF17/BCMA. TNFSF13/APRIL binds to the same 2 receptors. Together, they form a 2 ligands -2 receptors pathway involved in the stimulation of B- and T-cell function and the regulation of humoral immunity. A third B-cell specific BAFF-receptor (BAFFR/BR3) promotes the survival of mature B-cells and the B-cell response. (www.uniprot.org) Produced in E.coli. Single, non-glycosylated polypeptide chain containing 153 amino acids. The activity is determined by the dose-dependant stimulation of IL-8 production by human PBMC. The ED50 for this effect is less than 10ng/ml.