Fas Ligand (CD178 antigen, CD95L protein)

Fas is a type I membrane protein that belongs to the TNF/nerve growth factor receptor family. Fas mediates apoptosis, the programmed cell death, when it is cross-linked with specific binding partners. FasL is predominantly expressed on activated T-cells and NK cells; thus FasL-mediated cell death is involved in the T or NK cell-mediated cytotoxicity, some pathologic tissue damages, and the regulation of lymphocyte homeostasis. Elevated expression levels of FasL have been measured in various proliferative disorders and cancers.