Fas Ligand (FasL) is a member of the TNF superfamily that is expressed on the cell surface of activated T cells. Binding of FasL to Fas Receptor triggers apoptosis in Fas-bearing cells. FasL has the ability to kill T cells and activated B cells, which leads to down-regulation of the immune response. The mechanism of Fas-induced apoptosis involves recruitment of pro-caspase 8 through an adaptor molecule called FADD, followed by processing of the pro-enzyme into active forms. These active caspases then cleave various cellular substrates, leading to the eventual cell death. Both human and murine sFasL are fully active on human and murine cells. Recombinant Human soluble Fas Ligand is a 17.9 kDa protein comprising the TNF-homologous region of FasL and contains an 8-residue N-terminal His-Tag.
Amino Acid Sequence
Chinese Hamster Ovary Cells (CHO)
Determined by it's ability to induce cytotoxicity in Jurkat cells in the absence of any cross-linking. The ED50 for this effect is 10.0 ng/ml, corresponding to a specific activity of 1×105 units/mg.
Endotoxin level is <0.1 ng/μg of protein (<1EU/μg).
Centrifuge the vial prior to opening. Reconstitute in water to a concentration of 0.1–1.0 mg/ml. Do not vortex. For extended storage, it is recommended to further dilute in a buffer containing a carrier protein (example 0.1% BSA) and store in working aliquots at –20°C to –80°C