TRAIL is a 30 kD protein known as TNF-related apoptosis inducing ligand, CD253, TNFSF10, or Apo-2L. It can be expressed as a cell surface (30 kD) and soluble ligand (19-20 kD) produced by megakaryocytes and platelets, monocytes, neutrophils, NK cells and activated T cells. This antigen is also expressed on tumor cells and transformed cell lines. TRAIL has been reported to induce apoptosis in tumor and transformed cell lines by a caspase-dependent process. This antibody is useful for flow cytometric staining and blocking studies.