Tumor necrosis factor ligand superfamily member 15, also known TNFSF15, belongs to the TNF superfamily. TNFSF15 is predominantly expressed in endothelial cells and its expression is inducible by TNFalpha and IL1alpha. TNFSF15 is an angiogenesis inhibitor of the TNF family and functions in part by directly inhibiting endothelial cell proliferation. TNFSF15 may act as an autocrine factor to induce apoptosis in endothelial cells via activation of multiple signaling pathways, including stress protein kinases and certain caspases. Recombinant human TNFSF15 protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.