LIGHT , also known as TNFSF14 or CD258 , is a newly identified member of the TNF superfamily (TNFSF14) that is expressed by activated T lymphocytes , monocytes , granulocytes , spleen cells , and immature dendritic cells. TNFSF14 / LIGHT / CD258 is a type II transmembrane protein that is known to bind 2 membrane-bound TNFSF signaling receptors: HVEM , which is predominantly expressed by T cells , and lymphotoxin β receptor (LTβR) , which is expressed by stromal cells and nonlymphoid hematopoietic cells. TNFSF14 / LIGHT / CD258 also binds to a soluble non-signaling receptor , decoy receptor 3 (DcR3) , which can modulate the function of LIGHT in vivo. TNFSF14 / LIGHT / CD258 can also costimulate T cell responses via HVEM , which is constitutively expressed in most lymphocyte subpopulations , including CD4+ and CD8+ T cells. In addition , TNFSF14 / LIGHT / CD258 has been shown to suppress tumor formation in vivo and to induce tumor cell apoptosis via the up-regulation of intercellular adhesion molecule 1 and an increased lymphocyte adhesion to cancer cells. Thus , TNFSF14 / LIGHT / CD258 is being actively investigated as a possible basis for cancer treatment.