|
FcεRI
The high-affinity IgE receptor, also known as FcεRI, or Fc epsilon RI, is the high-affinity receptor for the Fc region of immunoglobulin E (IgE), an antibody isotype involved in allergy disorders and parasite immunity. FcεRI is a tetrameric receptor complex that binds Fc portion of the ε heavy chain of IgE. It consists of one alpha ( FcεRIα – antibody binding site), one beta ( FcεRIβ – which amplifies the downstream signal), and two gamma chains ( FcεRIγ – the site where the downstream signal initiates) connected by two disulfide bridges on mast cells and basophils. It lacks the beta subunit on other cells. It is constitutively expressed on mast cells and basophils and is inducible in eosinophils. Tissue distribution FcεRI is found on epidermal Langerhans cells, eosinophils, mast cells, and basophils. As a result of its cellular distribution, this receptor plays a major role in controlling allergic responses. FcεRI is also expressed on antigen-presenting c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FcεRI Receptor
The high-affinity IgE receptor, also known as FcεRI, or Fc epsilon RI, is the high-Affinity (pharmacology), affinity receptor (biochemistry), receptor for the Fc region of immunoglobulin E (IgE), an antibody Isotype (immunology), isotype involved in allergy disorders and parasitism, parasite immunity. FcεRI is a tetrameric protein, tetrameric receptor complex that binds Fc portion of the ε Immunoglobulin heavy chain, heavy chain of IgE. It consists of one alpha (FCER1A, FcεRIα – antibody binding site), one beta (FCER1B, FcεRIβ – which amplifies the downstream signal), and two gamma chains (FCER1G, FcεRIγ – the site where the downstream signal initiates) connected by two disulfide bridges on Mast cell, mast cells and Basophil, basophils. It lacks the beta subunit on other cells. It is constitutively expressed on mast cells and basophils and is inducible in Eosinophil, eosinophils. Tissue distribution FcεRI is found on epidermal Langerhans cells, eosinophils, ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunoglobulin E
Immunoglobulin E (IgE) is a type of antibody (or immunoglobulin (Ig) " isoform") that has been found only in mammals. IgE is synthesised by plasma cells. Monomers of IgE consist of two heavy chains (ε chain) and two light chains, with the ε chain containing four Ig-like constant domains (Cε1–Cε4). IgE is thought to be an important part of the immune response against infection by certain parasitic worms, including '' Schistosoma mansoni'', ''Trichinella spiralis'', and ''Fasciola hepatica''. IgE is also utilized during immune defense against certain protozoan parasites such as ''Plasmodium falciparum''. IgE may have evolved as a defense to protect against venoms. IgE also has an essential role in type I hypersensitivity, which manifests in various allergic diseases, such as allergic asthma, most types of sinusitis, allergic rhinitis, food allergies, and specific types of chronic urticaria and atopic dermatitis. IgE also plays a pivotal role in responses to allergens, such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IgE FcεRI Receptor Signal Cascade
Immunoglobulin E (IgE) is a type of antibody (or immunoglobulin (Ig) "isoform") that has been found only in mammals. IgE is synthesised by plasma cells. Monomers of IgE consist of two heavy chains (ε chain) and two light chains, with the ε chain containing four Ig-like constant domains (Cε1–Cε4). IgE is thought to be an important part of the immune response against infection by certain parasitic worms, including ''Schistosoma mansoni'', ''Trichinella spiralis'', and ''Fasciola hepatica''. IgE is also utilized during immune defense against certain protozoan parasites such as ''Plasmodium falciparum''. IgE may have evolved as a defense to protect against venoms. IgE also has an essential role in type I hypersensitivity, which manifests in various allergic diseases, such as allergic asthma, most types of sinusitis, allergic rhinitis, food allergies, and specific types of chronic urticaria and atopic dermatitis. IgE also plays a pivotal role in responses to allergens, such a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mast Cell
A mast cell (also known as a mastocyte or a labrocyte) is a resident cell of connective tissue that contains many granules rich in histamine and heparin. Specifically, it is a type of granulocyte derived from the myeloid stem cell that is a part of the immune and neuroimmune systems. Mast cells were discovered by Friedrich von Recklinghausen and later rediscovered by Paul Ehrlich in 1877. Although best known for their role in allergy and anaphylaxis, mast cells play an important protective role as well, being intimately involved in wound healing, angiogenesis, immune tolerance, defense against pathogens, and vascular permeability in brain tumors. The mast cell is very similar in both appearance and function to the basophil, another type of white blood cell. Although mast cells were once thought to be tissue-resident basophils, it has been shown that the two cells develop from different hematopoietic lineages and thus cannot be the same cells. Structure Mast cells ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allergy
Allergies, also known as allergic diseases, are various conditions caused by hypersensitivity of the immune system to typically harmless substances in the environment. These diseases include Allergic rhinitis, hay fever, Food allergy, food allergies, atopic dermatitis, allergic asthma, and anaphylaxis. Symptoms may include allergic conjunctivitis, red eyes, an itchy rash, sneeze, sneezing, coughing, a rhinorrhea, runny nose, shortness of breath, or swelling. Note that food intolerances and food poisoning are separate conditions. Common allergens include pollen and certain foods. Metals and other substances may also cause such problems. Food, insect stings, and medications are common causes of severe reactions. Their development is due to both genetic and environmental factors. The underlying mechanism involves immunoglobulin E antibodies (IgE), part of the body's immune system, binding to an allergen and then to FcεRI, a receptor on mast cells or basophils where it triggers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FCER1G
Fc fragment of IgE, high affinity I, receptor for; gamma polypeptide is gamma chain of high affinity IgE receptor. This protein is encoded by the FCER1G gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ... in humans. Function The high affinity IgE receptor, FcεRI, is a key molecule involved in allergic reactions. It is a tetramer composed of 1 alpha, 1 beta, and 2 gamma chains. The gamma chains are also subunits of other Fc receptors. rovided by RefSeq, Jul 2008 References Further reading * * * * * * * * * Genes on human chromosome 1 {{gene-1-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FCER1B
High affinity immunoglobulin epsilon receptor subunit beta is a protein that in humans is encoded by the ''MS4A2'' gene. Function The allergic response involves the binding of allergen to receptor-bound IgE followed by cell activation and the release of mediators responsible for the manifestations of allergy. The IgE-receptor, a tetramer composed of an alpha, beta, and 2 disulfide-linked gamma chains, is found on the surface of mast cells and basophils. This gene encodes the beta subunit of the high affinity IgE receptor which is a member of the membrane-spanning 4A gene family. Members of this nascent protein family are characterized by common structural features and similar intron/exon splice boundaries and display unique expression patterns among hematopoietic cells and nonlymphoid tissues. This family member is localized to 11q12, among a cluster of family members. See also * FcεRI The high-affinity IgE receptor, also known as FcεRI, or Fc epsilon RI, is the high-aff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basophil
Basophils are a type of white blood cell White blood cells (scientific name leukocytes), also called immune cells or immunocytes, are cells of the immune system that are involved in protecting the body against both infectious disease and foreign entities. White blood cells are genera .... Basophils are the least common type of granulocyte, representing about 0.5% to 1% of circulating white blood cells. They are the largest type of granulocyte. They are responsible for inflammatory reactions during immune response, as well as in the formation of acute and chronic allergic diseases, including anaphylaxis, asthma, atopic dermatitis and Hay Fever, hay fever. They also produce compounds that coordinate immune responses, including histamine and serotonin that induce inflammation, and heparin that prevents Coagulation, blood clotting, although there are less than that found in mast cell granules. Mast cells were once thought to be basophils that migrated from the blood into their r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antibody
An antibody (Ab) or immunoglobulin (Ig) is a large, Y-shaped protein belonging to the immunoglobulin superfamily which is used by the immune system to identify and neutralize antigens such as pathogenic bacteria, bacteria and viruses, including those that cause disease. Each individual antibody recognizes one or more specific antigens, and antigens of virtually any size and chemical composition can be recognized. Antigen literally means "antibody generator", as it is the presence of an antigen that drives the formation of an antigen-specific antibody. Each of the branching chains comprising the "Y" of an antibody contains a paratope that specifically binds to one particular epitope on an antigen, allowing the two molecules to bind together with precision. Using this mechanism, antibodies can effectively "tag" the antigen (or a microbe or an infected cell bearing such an antigen) for attack by cells of the immune system, or can neutralize it directly (for example, by blocking a p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FCER1A
Fc fragment of IgE, high affinity I, receptor for; alpha polypeptide, also known as FCER1A, is a protein which in humans is encoded by the ''FCER1A'' gene. Function The high affinity IgE receptor plays a central role in allergic disease, coupling allergen and mast cell to initiate the inflammatory and immediate hypersensitivity responses that are characteristic of disorders such as hay fever and asthma. The allergic response occurs when 2 or more IgE receptors are crosslinked via IgE molecules that in turn are bound to an allergen (antigen) molecule. A perturbation occurs that brings about the release of histamine and proteases from the granules in the cytoplasm of the mast cell and leads to the synthesis of prostaglandins and leukotrienes—potent effectors of the hypersensitivity response. The IgE receptor consists of 3 subunits: alpha (this protein), beta, and gamma; only the alpha subunit is glycosylated Glycosylation is the reaction in which a carbohydrate (or ' glyca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Affinity (pharmacology)
In biochemistry and pharmacology, a ligand is a substance that forms a complex with a biomolecule to serve a biological purpose. The etymology stems from Latin ''ligare'', which means 'to bind'. In protein-ligand binding, the ligand is usually a molecule which produces a signal by binding to a site on a target protein. The binding typically results in a change of conformational isomerism (conformation) of the target protein. In DNA-ligand binding studies, the ligand can be a small molecule, ion, or protein which binds to the DNA double helix. The relationship between ligand and binding partner is a function of charge, hydrophobicity, and molecular structure. Binding occurs by intermolecular forces, such as ionic bonds, hydrogen bonds and Van der Waals forces. The association or docking is actually reversible through dissociation. Measurably irreversible covalent bonding between a ligand and target molecule is atypical in biological systems. In contrast to the definition o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
