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Death Receptor 3
Death receptor 3 (DR3), also known as tumor necrosis factor receptor superfamily member 25 (TNFRSF25), is a cell surface receptor of the tumor necrosis factor receptor superfamily which mediates apoptotic signalling and differentiation. Its only known TNFSF ligand is TNF-like protein 1A (TL1A). Function The protein encoded by this gene is a member of the TNF-receptor superfamily. This receptor is expressed preferentially by activated and antigen-experienced T lymphocytes. TNFRSF25 is also highly expressed by FoxP3 positive regulatory T lymphocytes. TNFRSF25 is activated by a monogamous ligand, known as TL1A (TNFSF15), which is rapidly upregulated in antigen presenting cells and some endothelial cells following Toll-Like Receptor or Fc receptor activation. This receptor has been shown to signal both through the TRADD adaptor molecule to stimulate NF-kappa B activity or through the FADD adaptor molecule to stimulate caspase activation and regulate cell apoptosis. Multiple altern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Surface Receptor
Cell surface receptors (membrane receptors, transmembrane receptors) are receptors that are embedded in the plasma membrane of cells. They act in cell signaling by receiving (binding to) extracellular molecules. They are specialized integral membrane proteins that allow communication between the cell and the extracellular space. The extracellular molecules may be hormones, neurotransmitters, cytokines, growth factors, cell adhesion molecules, or nutrients; they react with the receptor to induce changes in the metabolism and activity of a cell. In the process of signal transduction, ligand binding affects a cascading chemical change through the cell membrane. Structure and mechanism Many membrane receptors are transmembrane proteins. There are various kinds, including glycoproteins and lipoproteins. Hundreds of different receptors are known and many more have yet to be studied. Transmembrane receptors are typically classified based on their tertiary (three-dimensional) stru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tumor Necrosis Factor Receptor
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] |
Apoptosis
Apoptosis (from grc, ἀπόπτωσις, apóptōsis, 'falling off') is a form of programmed cell death that occurs in multicellular organisms. Biochemical events lead to characteristic cell changes (morphology) and death. These changes include blebbing, cell shrinkage, nuclear fragmentation, chromatin condensation, DNA fragmentation, and mRNA decay. The average adult human loses between 50 and 70 billion cells each day due to apoptosis. For an average human child between eight and fourteen years old, approximately twenty to thirty billion cells die per day. In contrast to necrosis, which is a form of traumatic cell death that results from acute cellular injury, apoptosis is a highly regulated and controlled process that confers advantages during an organism's life cycle. For example, the separation of fingers and toes in a developing human embryo occurs because cells between the digits undergo apoptosis. Unlike necrosis, apoptosis produces cell fragments called apoptotic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Differentiation
Cellular differentiation is the process in which a stem cell alters from one type to a differentiated one. Usually, the cell changes to a more specialized type. Differentiation happens multiple times during the development of a multicellular organism as it changes from a simple zygote to a complex system of tissues and cell types. Differentiation continues in adulthood as adult stem cells divide and create fully differentiated daughter cells during tissue repair and during normal cell turnover. Some differentiation occurs in response to antigen exposure. Differentiation dramatically changes a cell's size, shape, membrane potential, metabolic activity, and responsiveness to signals. These changes are largely due to highly controlled modifications in gene expression and are the study of epigenetics. With a few exceptions, cellular differentiation almost never involves a change in the DNA sequence itself. Although metabolic composition does get altered quite dramatica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TNF-like Protein 1A
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. Function The protein encoded by this gene is a cytokine that belongs to the tumor necrosis factor (TNF) ligand family. This protein is abundantly expressed in endothelial cells, but is not expressed in either B or T cells. The expression of this protein is inducible by TNF-alpha and IL-1 alpha. This cytokine is a ligand for receptor TNFRSF25 (death receptor 3) and TNFRSF6B (decoy receptor 3). It can activate both the NF-κB and MAPK signalling pathways, and acts as an autocrine factor to induce apoptosis in endothelial cells. This cytokine is also found to inhibit endothelial ce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TRADD
Tumor necrosis factor receptor type 1-associated DEATH domain protein is a protein that in humans is encoded by the ''TRADD'' gene. TRADD is an adaptor protein. Function The protein encoded by this gene is a death domain containing adaptor molecule that interacts with TNFRSF1A/TNFR1 and mediates programmed cell death signaling and NF-κB activation. This protein binds adaptor protein TRAF2, reduces the recruitment of inhibitor-of-apoptosis proteins (IAPs) by TRAF2, and thus suppresses TRAF2 mediated apoptosis. This protein can also interact with receptor TNFRSF6/ FAS and adaptor protein FADD/MORT1, and is involved in the Fas-induced cell death pathway. Interactions TRADD has been shown to interact with: * FADD, * Keratin 18 * RIPK1, * STAT1, * TNFRSF1A, * TNFRSF25, and * TRAF2. See also * TRAF * RIP Rest in peace (RIP), a phrase from the Latin (), is sometimes used in traditional Christian services and prayers, such as in the Catholic, Lutheran, Anglican, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FADD
FAS-associated death domain protein, also called MORT1, is encoded by the ''FADD'' gene on the 11q13.3 region of chromosome 11 in humans. FADD is an adaptor protein that bridges members of the tumor necrosis factor receptor superfamily, such as the Fas-receptor, to procaspases 8 and 10 to form the death-inducing signaling complex (DISC) during apoptosis. As well as its most well known role in apoptosis, FADD has also been seen to play a role in other processes including proliferation, cell cycle regulation and development. Structure FADD is a 23 kDa protein, made up of 208 amino acids. It contains two main domains: a C terminal death domain (DD) and an N terminal death effector domain (DED). Each domain, although sharing very little sequence similarity, are structurally similar to one another, with each consisting of 6 α helices. The DD of FADD binds to receptors such as the Fas receptor at the plasma membrane via their DD. The interaction between the death domains are elec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Regulatory T Cell
The regulatory T cells (Tregs or Treg cells), formerly known as suppressor T cells, are a subpopulation of T cells that modulate the immune system, maintain tolerance to self-antigens, and prevent autoimmune disease. Treg cells are immunosuppressive and generally suppress or downregulate induction and proliferation of effector T cells. Treg cells express the biomarkers CD4, FOXP3, and CD25 and are thought to be derived from the same lineage as naïve CD4+ cells. Because effector T cells also express CD4 and CD25, Treg cells are very difficult to effectively discern from effector CD4+, making them difficult to study. Research has found that the cytokine transforming growth factor beta (TGF-β) is essential for Treg cells to differentiate from naïve CD4+ cells and is important in maintaining Treg cell homeostasis. Mouse models have suggested that modulation of Treg cells can treat autoimmune disease and cancer and can facilitate orga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asthma
Asthma is a long-term inflammatory disease of the airways of the lungs. It is characterized by variable and recurring symptoms, reversible airflow obstruction, and easily triggered bronchospasms. Symptoms include episodes of wheezing, coughing, chest tightness, and shortness of breath. These may occur a few times a day or a few times per week. Depending on the person, asthma symptoms may become worse at night or with exercise. Asthma is thought to be caused by a combination of genetic and environmental factors. Environmental factors include exposure to air pollution and allergens. Other potential triggers include medications such as aspirin and beta blockers. Diagnosis is usually based on the pattern of symptoms, response to therapy over time, and spirometry lung function testing. Asthma is classified according to the frequency of symptoms, forced expiratory volume in one second (FEV1), and peak expiratory flow rate. It may also be classified as atopic or non-atopic, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allotransplantation
Allotransplant (''allo-'' meaning "other" in Greek) is the transplantation of cells, tissues, or organs to a recipient from a genetically non-identical donor of the same species. The transplant is called an allograft, allogeneic transplant, or homograft. Most human tissue and organ transplants are allografts. It is contrasted with autotransplantation (from one part of the body to another in the same person), syngenic transplantation of isografts (grafts transplanted between two genetically identical individuals) and xenotransplantation (from other species). Allografts can be referred to as "homostatic" if they are biologically inert when transplanted, such as bone and cartilage. An immune response against an allograft or xenograft is termed rejection. An allogenic bone marrow transplant can result in an immune attack on the recipient, called graft-versus-host disease. Procedure Material is obtained from a donor who is a living person, or a deceased person's body receiving ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Keratitis
Keratitis is a condition in which the eye's cornea, the clear dome on the front surface of the eye, becomes inflamed. The condition is often marked by moderate to intense pain and usually involves any of the following symptoms: pain, impaired eyesight, photophobia (light sensitivity), red eye and a 'gritty' sensation. Classification (by chronicity) Acute * Acute epithelial keratitis * Nummular keratitis * Interstitial keratitis * Disciform keratitis Chronic * Neurotrophic keratitis * Mucous plaque keratitis Classification (infective) Viral * Herpes simplex keratitis (dendritic keratitis). Viral infection of the cornea is often caused by the herpes simplex virus (HSV) which frequently leaves what is called a 'dendritic ulcer'. * Herpes zoster keratitis, associated with herpes zoster ophthalmicus, which is a form of shingles. Bacterial * Bacterial keratitis. Bacterial infection of the cornea can follow from an injury or from wearing contact lenses. The bacteria involved ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CTLA-4
CTLA-4 or CTLA4 (cytotoxic T-lymphocyte-associated protein 4), also known as CD152 (cluster of differentiation 152), is a protein receptor that functions as an immune checkpoint and downregulates immune responses. CTLA-4 is constitutively expressed in regulatory T cells but only upregulated in conventional T cells after activation – a phenomenon which is particularly notable in cancers. It acts as an "off" switch when bound to CD80 or CD86 on the surface of antigen-presenting cells. The CTLA-4 protein is encoded by the ''Ctla-4'' gene in mice and the ''CTLA-4'' gene in humans. History CTLA-4 was first identified in 1991 as a second receptor for the T cell costimulation ligand B7. In November 1995, the labs of Tak Wah Mak and Arlene H. Sharpe independently published their findings on the discovery of the function of CTLA-4 as a negative regulator of T-cell activation, by knocking out the gene in mice. Previous studies from several labs had used methods which could not def ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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