TNFSF14, also known as tumor necrosis factor ligand superfamily member 14 or LIGHT (homologous to lymphotoxins, exhibits inducible expression, and competes with HSV glycoprotein D for HVEM, a receptor expressed by T lymphocytes), is a cytokine belonging to the tumor necrosis factor (TNF) superfamily. TNFSF14 is a type II transmembrane protein that can be cleaved to produce a soluble form. It functions as a ligand for two receptors, herpes virus entry mediator (HVEM) and lymphotoxin beta receptor (LTβR), and is involved in regulating immune responses, inflammation, and lymphoid organ development. TNFSF14 has been implicated in various physiological and pathological processes, including the modulation of T cell activation, the regulation of immune cell migration, and the promotion of antitumor immunity.