LIGHT is a type II membrane protein belonging to the TNF family of membrane-anchored ligands. It is expressed in splenocytes, activated PBL, CD8+ tumor infiltrating lymphocytes, granulocytes and monocytes. LIGHT has the ability to activate NFkB, stimulate proliferation of lymphocytes, and induce apoptosis in certain human tumor cells. LIGHT binds to three receptors; the herpes virus entry mediator type A receptor (HEVM), LTbR and a decoy receptor (DcR3).