LIGHT, also known as tumor necrosis factor superfamily member 14 (TNFSF14), is a secreted protein of the TNF superfamily. [5] [6] [7] It is recognized by herpesvirus entry mediator (HVEM), as well as decoy receptor 3.
LIGHT stands for "homologous to lymphotoxin, exhibits inducible expression and competes with HSV glycoprotein D for binding to herpesvirus entry mediator, a receptor expressed on T lymphocytes". In the cluster of differentiation terminology it is classified as CD258.
The protein encoded by this gene is a member of the tumor necrosis factor (TNF) ligand family. This protein is a ligand for TNFRSF14, which is a member of the tumor necrosis factor receptor superfamily, and which is also known as a herpesvirus entry mediator (HVEM). Two alternatively spliced transcript variant encoding distinct isoforms have been reported. [6]
This protein may function as a costimulatory factor for the activation of lymphoid cells and as a deterrent to infection by herpesvirus. This protein has been shown to stimulate the proliferation of T cells, [8] trigger apoptosis of various tumor cells [9] and play a role in vascular normalisation processes. [10] This protein is also reported to prevent tumor necrosis factor alpha-mediated apoptosis in primary hepatocytes. [11]
LIGHT has been shown to interact with TNFRSF14, [12] [13] TNFRSF6B, [12] [13] [14] BIRC2, [15] TRAF2 [15] and TRAF3. [15]
Similar to how CD4 is the primary mediating receptor in HIV infection, the HSV glycoprotein (gD) binds to the HVEM receptor which is demanded by TNFSF14/LIGHT lowering the ability for LIGHT to activate the NFκB pathway. NFκB is a survival factor helping to inhibit apoptosis which triggers a pathway inhibiting caspase 8. When gD from HSV binds to HVEM, LIGHT is non-competitively inhibited from binding, encouraging apoptosis in the infected cell. [7]
Lymphotoxin is a member of the tumor necrosis factor (TNF) superfamily of cytokines, whose members are responsible for regulating the growth and function of lymphocytes and are expressed by a wide variety of cells in the body.
The Fas receptor, also known as Fas, FasR, apoptosis antigen 1, cluster of differentiation 95 (CD95) or tumor necrosis factor receptor superfamily member 6 (TNFRSF6), is a protein that in humans is encoded by the FAS gene. Fas was first identified using a monoclonal antibody generated by immunizing mice with the FS-7 cell line. Thus, the name Fas is derived from FS-7-associated surface antigen.
TNF receptor-associated factor 2 is a protein that in humans is encoded by the TRAF2 gene.
Lymphotoxin beta receptor (LTBR), also known as tumor necrosis factor receptor superfamily member 3 (TNFRSF3), is a cell surface receptor for lymphotoxin involved in apoptosis and cytokine release. It is a member of the tumor necrosis factor receptor superfamily.
Tumor necrosis factor receptor 1 (TNFR1), also known as tumor necrosis factor receptor superfamily member 1A (TNFRSF1A) and CD120a, is a ubiquitous membrane receptor that binds tumor necrosis factor-alpha (TNFα).
Death receptor 4 (DR4), also known as TRAIL receptor 1 (TRAILR1) and tumor necrosis factor receptor superfamily member 10A (TNFRSF10A), is a cell surface receptor of the TNF-receptor superfamily that binds TRAIL and mediates apoptosis.
TNF receptor-associated factor 5 is a protein that in humans is encoded by the TRAF5 gene.
Lymphotoxin-alpha (LT-α) formerly known as tumor necrosis factor-beta (TNF-β) is a protein that in humans is encoded by the LTA gene. Belonging to the hematopoietic cell line, LT-α exhibits anti-proliferative activity and causes the cellular destruction of tumor cell lines. As a cytotoxic protein, LT-α performs a variety of important roles in immune regulation depending on the form that it is secreted as. Unlike other members of the TNF superfamily, LT-α is only found as a soluble homotrimer, when found at the cell surface it is found only as a heterotrimer with LTβ.
TNF receptor-associated factor (TRAF3) is a protein that in humans is encoded by the TRAF3 gene.
Lymphotoxin-beta (LT-beta) also known as tumor necrosis factor C (TNF-C) is a protein that in humans is encoded by the LTB gene.
A proliferation-inducing ligand (APRIL), also known as tumor necrosis factor ligand superfamily member 13 (TNFSF13), is a protein of the TNF superfamily recognized by the cell surface receptor TACI. It is encoded by the TNFSF13 gene.
Herpesvirus entry mediator (HVEM), also known as tumor necrosis factor receptor superfamily member 14 (TNFRSF14), is a human cell surface receptor of the TNF-receptor superfamily encoded by the TNFRSF14 gene.
Tumor necrosis factor ligand superfamily member 12 also known as TNF-related weak inducer of apoptosis (TWEAK) is a protein that in humans is encoded by the TNFSF12 gene.
Decoy receptor 3 (Dcr3), also known as tumor necrosis factor receptor superfamily member 6B (TNFRSF6B), TR6 and M68, is a soluble protein of the tumor necrosis factor receptor superfamily which inhibits Fas ligand-induced apoptosis.
Decoy receptor 1 (DCR1), also known as TRAIL receptor 3 (TRAILR3) and tumor necrosis factor receptor superfamily member 10C (TNFRSF10C), is a human cell surface receptor of the TNF-receptor superfamily.
Decoy receptor 2 (DCR2), also known as TRAIL receptor 4 (TRAILR4) and tumor necrosis factor receptor superfamily member 10D (TNFRSF10D), is a human cell surface receptor of the TNF-receptor superfamily.
Tumor necrosis factor receptor superfamily member 12A also known as the TWEAK receptor (TWEAKR) is a protein that in humans is encoded by the TNFRSF12A gene.
Vascular endothelial growth inhibitor (VEGI), also known as TNF-like ligand 1A (TL1A) and TNF superfamily member 15 (TNFSF15), is protein that in humans is encoded by the TNFSF15 gene. VEGI is an anti-angiogenic protein. It belongs to tumor necrosis factor (ligand) superfamily, where it is member 15. It is the sole known ligand for death receptor 3, and it can also be recognized by decoy receptor 3.
B- and T-lymphocyte attenuator or BTLA is a protein that belongs to the CD28 immunoglobulin superfamily (IgSF) which is encoded by the BTLA gene located on the 3rd human chromosome. BTLA was first discovered in 2003 as an inhibitor of Th1 expansion and it became the 3rd member of the CD28 IgSF. However, its discovered ligand herpes virus entry mediator or HVEM belongs to the tumor necrosis factor receptor superfamily (TNFRSF). This finding was surprising because until the discovery of HVEM it was believed that receptors and ligands always belong to the same family.
Tumor necrosis factor receptor 2 (TNFR2), also known as tumor necrosis factor receptor superfamily member 1B (TNFRSF1B) and CD120b, is one of two membrane receptors that binds tumor necrosis factor-alpha (TNFα). Like its counterpart, tumor necrosis factor receptor 1 (TNFR1), the extracellular region of TNFR2 consists of four cysteine-rich domains which allow for binding to TNFα. TNFR1 and TNFR2 possess different functions when bound to TNFα due to differences in their intracellular structures, such as TNFR2 lacking a death domain (DD).
This article incorporates text from the United States National Library of Medicine, which is in the public domain.