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Lymphotoxin
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. Lymphotoxin plays a critical role in developing and preserving the framework of lymphoid organs and of gastrointestinal immune responses, as well as in the activation signaling of both the innate and adaptive immune responses. Lymphotoxin alpha (LT-α, previously known as TNF-beta) and lymphotoxin beta (LT-β), the two forms of lymphotoxin, each have distinctive structural characteristics and perform specific functions. Structure and function Each LT-α/LT-β subunit is a trimer and assembles into homotrimers or heterotrimers. LT-α binds with LT-β to form membrane-bound heterotrimers LT-α1-β2 and LT-α2-β1, which are commonly referred to as lymphotoxin beta. LT-α1-β2 is the most prevalent form of lymphotoxin beta. LT-α also forms a homotrimer, LT ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lymphotoxin Alpha
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. LT-α has a significant impact on the maintenance of the immune system including the development of secondary lymphoid organs. Absence of LT-α leads to the disruption of gastrointestinal development, prevents Peyer's patch development, and results in a disorganized spleen. As a signaling molecule, LT-α is involved in the regulation of cell survival, proliferation, differentiation, and apoptosis. L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lymphotoxin Alpha
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. LT-α has a significant impact on the maintenance of the immune system including the development of secondary lymphoid organs. Absence of LT-α leads to the disruption of gastrointestinal development, prevents Peyer's patch development, and results in a disorganized spleen. As a signaling molecule, LT-α is involved in the regulation of cell survival, proliferation, differentiation, and apoptosis. L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lymphotoxin Beta Receptor
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. Function The protein encoded by this gene is a member of the tumor necrosis factor (TNF) family of receptors. It is expressed on the surface of most cell types, including cells of epithelial and myeloid lineages, but not on T and B lymphocytes. The protein specifically binds the lymphotoxin membrane form (a complex of lymphotoxin-alpha and lymphotoxin-beta). The encoded protein and its ligand play a role in the development and organization of lymphoid tissue and transformed cells. Activation of the encoded protein can trigger apoptosis. Not only does the LTBR help trigger apoptosis, it can lead to the release of the cytokine interleukin 8. Overexpression of LTBR in HEK293 cells increases IL-8 promoter activity and le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lymphotoxin Beta Receptor
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. Function The protein encoded by this gene is a member of the tumor necrosis factor (TNF) family of receptors. It is expressed on the surface of most cell types, including cells of epithelial and myeloid lineages, but not on T and B lymphocytes. The protein specifically binds the lymphotoxin membrane form (a complex of lymphotoxin-alpha and lymphotoxin-beta). The encoded protein and its ligand play a role in the development and organization of lymphoid tissue and transformed cells. Activation of the encoded protein can trigger apoptosis. Not only does the LTBR help trigger apoptosis, it can lead to the release of the cytokine interleukin 8. Overexpression of LTBR in HEK293 cells increases IL-8 promoter activity and le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lymphotoxin Beta
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. Function Lymphotoxin beta is a type II membrane protein of the TNF family. It anchors lymphotoxin-alpha to the cell surface through heterotrimer formation. The predominant form on the lymphocyte surface is the lymphotoxin-alpha 1/beta 2 complex (e.g. 1 molecule alpha/2 molecules beta) and this complex is the primary ligand for the lymphotoxin-beta receptor. The minor complex is lymphotoxin-alpha 2/beta 1. LTB is an inducer of the inflammatory response system and involved in normal development of lymphoid tissue. Lymphotoxin-beta isoform b is unable to complex with lymphotoxin-alpha suggesting a function for lymphotoxin-beta which is independent of lymphotoxin-alpha. Alternative splicing results in multiple transcript variants encoding different isoforms. Pro-tumorigenic function of membrane LT is clearly established: mice with overexpression of L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NF-κB
Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) is a protein complex that controls transcription of DNA, cytokine production and cell survival. NF-κB is found in almost all animal cell types and is involved in cellular responses to stimuli such as stress, cytokines, free radicals, heavy metals, ultraviolet irradiation, oxidized LDL, and bacterial or viral antigens. NF-κB plays a key role in regulating the immune response to infection. Incorrect regulation of NF-κB has been linked to cancer, inflammatory and autoimmune diseases, septic shock, viral infection, and improper immune development. NF-κB has also been implicated in processes of synaptic plasticity and memory. Discovery NF-κB was discovered by Ranjan Sen in the lab of Nobel laureate David Baltimore via its interaction with an 11-base pair sequence in the immunoglobulin light-chain enhancer in B cells. Later work by Alexander Poltorak and Bruno Lemaitre in mice and ''Drosophila'' frui ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Herpesvirus Entry Mediator
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. Nomenclature This protein was originally known as herpesvirus entry mediator A (HveA); HveB and HveC are structurally unrelated proteins of the immunoglobulin superfamily. It is also known as CD270 in the cluster of differentiation classification. Moreover, it is also referred to as ATAR (another TRAF-associated receptor). Function The protein encoded by this gene is a member of the TNF-receptor superfamily. The cytoplasmic region of this receptor was found to bind to several TNF receptor associated factor (TRAF) family members, which may mediate the signal transduction pathways that activate the immune response. In melanocytic cells TNFRSF14 gene expression may be regulated by MITF. Interactions TNFRSF14 has been shown to interact with TRAF2, TNFSF14 and TRAF5. Clinical relevance Mutations in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TNF Receptor Superfamily
The tumor necrosis factor receptor superfamily (TNFRSF) is a protein superfamily of cytokine receptors characterized by the ability to bind tumor necrosis factors (TNFs) via an extracellular cysteine-rich domain. With the exception of nerve growth factor (NGF), all TNFs are homologous to the archetypal TNF-alpha. In their active form, the majority of TNF receptors form trimeric complexes in the plasma membrane. Accordingly, most TNF receptors contain transmembrane domains (TMDs), although some can be cleaved into soluble forms (e.g. TNFR1), and some lack a TMD entirely (e.g. DcR3). In addition, most TNF receptors require specific adaptor protein such as TRADD, TRAF, RIP and FADD for downstream signalling. TNF receptors are primarily involved in apoptosis and inflammation, but they can also take part in other signal transduction pathways, such as proliferation, survival, and differentiation. TNF receptors are expressed in a wide variety of tissues in mammals, especially in leukocy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melanoma
Melanoma, also redundantly known as malignant melanoma, is a type of skin cancer that develops from the pigment-producing cells known as melanocytes. Melanomas typically occur in the skin, but may rarely occur in the mouth, intestines, or eye (uveal melanoma). In women, they most commonly occur on the legs, while in men, they most commonly occur on the back. About 25% of melanomas develop from moles. Changes in a mole that can indicate melanoma include an increase in size, irregular edges, change in color, itchiness, or skin breakdown. The primary cause of melanoma is ultraviolet light (UV) exposure in those with low levels of the skin pigment melanin. The UV light may be from the sun or other sources, such as tanning devices. Those with many moles, a history of affected family members, and poor immune function are at greater risk. A number of rare genetic conditions, such as xeroderma pigmentosum, also increase the risk. Diagnosis is by biopsy and analysis of any skin lesion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multiple Myeloma
Multiple myeloma (MM), also known as plasma cell myeloma and simply myeloma, is a cancer of plasma cells, a type of white blood cell that normally produces antibodies. Often, no symptoms are noticed initially. As it progresses, bone pain, anemia, kidney dysfunction, and infections may occur. Complications may include amyloidosis. The cause of multiple myeloma is unknown. Risk factors include obesity, radiation exposure, family history, and certain chemicals. There is an increased risk of multiple myeloma in certain occupations. This is due to the occupational exposure to aromatic hydrocarbon solvents having a role in causation of multiple myeloma. Multiple myeloma may develop from monoclonal gammopathy of undetermined significance that progresses to smoldering myeloma. The abnormal plasma cells produce abnormal antibodies, which can cause kidney problems and overly thick blood. The plasma cells can also form a mass in the bone marrow or soft tissue. When one tumor i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytotoxicity
Cytotoxicity is the quality of being toxic to cells. Examples of toxic agents are an immune cell or some types of venom, e.g. from the puff adder (''Bitis arietans'') or brown recluse spider (''Loxosceles reclusa''). Cell physiology Treating cells with the cytotoxic compound can result in a variety of cell fates. The cells may undergo necrosis, in which they lose membrane integrity and die rapidly as a result of cell lysis. The cells can stop actively growing and dividing (a decrease in cell viability), or the cells can activate a genetic program of controlled cell death (apoptosis). Cells undergoing necrosis typically exhibit rapid swelling, lose membrane integrity, shut down metabolism, and release their contents into the environment. Cells that undergo rapid necrosis in vitro do not have sufficient time or energy to activate apoptotic machinery and will not express apoptotic markers. Apoptosis is characterized by well defined cytological and molecular events including a change i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Killer T Cell
Natural killer T (NKT) cells are a heterogeneous group of T cells that share properties of both T cells and natural killer cells. Many of these cells recognize the non-polymorphic CD1d molecule, an antigen-presenting molecule that binds self and foreign lipids and glycolipids. They constitute only approximately 1% of all peripheral blood T cells. Natural killer T cells should neither be confused with natural killer cells nor killer T cells (cytotoxic T cells). Nomenclature The term "NK T cells" was first used in mice to define a subset of T cells that expressed the natural killer (NK) cell-associated marker NK1.1 (CD161). It is now generally accepted that the term "NKT cells" refers to CD1d-restricted T cells, present in mice and humans, some of which coexpress a heavily biased, semi-invariant T-cell receptor and NK cell markers. Molecular characterization NKT cells are a subset of T cells that coexpress an αβ T-cell receptor, but also express a variety of molecular marke ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
