Receptors, Histamine: Cell-surface proteins that bind histamine and trigger intracellular changes influencing the behavior of cells. Histamine receptors are widespread in the central nervous system and in peripheral tissues. Three types have been recognized and designated H1, H2, and H3. They differ in pharmacology, distribution, and mode of action.Histamine: An amine derived by enzymatic decarboxylation of HISTIDINE. It is a powerful stimulant of gastric secretion, a constrictor of bronchial smooth muscle, a vasodilator, and also a centrally acting neurotransmitter.Mast Cells: Granulated cells that are found in almost all tissues, most abundantly in the skin and the gastrointestinal tract. Like the BASOPHILS, mast cells contain large amounts of HISTAMINE and HEPARIN. Unlike basophils, mast cells normally remain in the tissues and do not circulate in the blood. Mast cells, derived from the bone marrow stem cells, are regulated by the STEM CELL FACTOR.Receptors, Histamine H1: A class of histamine receptors discriminated by their pharmacology and mode of action. Most histamine H1 receptors operate through the inositol phosphate/diacylglycerol second messenger system. Among the many responses mediated by these receptors are smooth muscle contraction, increased vascular permeability, hormone release, and cerebral glyconeogenesis. (From Biochem Soc Trans 1992 Feb;20(1):122-5)Receptors, Histamine H2: A class of histamine receptors discriminated by their pharmacology and mode of action. Histamine H2 receptors act via G-proteins to stimulate ADENYLYL CYCLASES. Among the many responses mediated by these receptors are gastric acid secretion, smooth muscle relaxation, inotropic and chronotropic effects on heart muscle, and inhibition of lymphocyte function. (From Biochem Soc Trans 1992 Feb;20(1):122-5)Histamine Antagonists: Drugs that bind to but do not activate histamine receptors, thereby blocking the actions of histamine or histamine agonists. Classical antihistaminics block the histamine H1 receptors only.Histamine Agonists: Drugs that bind to and activate histamine receptors. Although they have been suggested for a variety of clinical applications histamine agonists have so far been more widely used in research than therapeutically.Histamine H1 Antagonists: Drugs that selectively bind to but do not activate histamine H1 receptors, thereby blocking the actions of endogenous histamine. Included here are the classical antihistaminics that antagonize or prevent the action of histamine mainly in immediate hypersensitivity. They act in the bronchi, capillaries, and some other smooth muscles, and are used to prevent or allay motion sickness, seasonal rhinitis, and allergic dermatitis and to induce somnolence. The effects of blocking central nervous system H1 receptors are not as well understood.Receptors, Histamine H3: A class of histamine receptors discriminated by their pharmacology and mode of action. Histamine H3 receptors were first recognized as inhibitory autoreceptors on histamine-containing nerve terminals and have since been shown to regulate the release of several neurotransmitters in the central and peripheral nervous systems. (From Biochem Soc Trans 1992 Feb;20(1):122-5)Pyrilamine: A histamine H1 antagonist. It has mild hypnotic properties and some local anesthetic action and is used for allergies (including skin eruptions) both parenterally and locally. It is a common ingredient of cold remedies.Methylhistamines: Histamine substituted in any position with one or more methyl groups. Many of these are agonists for the H1, H2, or both histamine receptors.Histamine Release: The secretion of histamine from mast cell and basophil granules by exocytosis. This can be initiated by a number of factors, all of which involve binding of IgE, cross-linked by antigen, to the mast cell or basophil's Fc receptors. Once released, histamine binds to a number of different target cell receptors and exerts a wide variety of effects.Histamine H2 Antagonists: Drugs that selectively bind to but do not activate histamine H2 receptors, thereby blocking the actions of histamine. Their clinically most important action is the inhibition of acid secretion in the treatment of gastrointestinal ulcers. Smooth muscle may also be affected. Some drugs in this class have strong effects in the central nervous system, but these actions are not well understood.Dimaprit: A histamine H2 receptor agonist that is often used to study the activity of histamine and its receptors.Cimetidine: A histamine congener, it competitively inhibits HISTAMINE binding to HISTAMINE H2 RECEPTORS. Cimetidine has a range of pharmacological actions. It inhibits GASTRIC ACID secretion, as well as PEPSIN and GASTRIN output.Diphenhydramine: A histamine H1 antagonist used as an antiemetic, antitussive, for dermatoses and pruritus, for hypersensitivity reactions, as a hypnotic, an antiparkinson, and as an ingredient in common cold preparations. It has some undesired antimuscarinic and sedative effects.Impromidine: A highly potent and specific histamine H2 receptor agonist. It has been used diagnostically as a gastric secretion indicator.Metiamide: A histamine H2 receptor antagonist that is used as an anti-ulcer agent.Chlorpheniramine: A histamine H1 antagonist used in allergic reactions, hay fever, rhinitis, urticaria, and asthma. It has also been used in veterinary applications. One of the most widely used of the classical antihistaminics, it generally causes less drowsiness and sedation than PROMETHAZINE.Histidine Decarboxylase: An enzyme that catalyzes the decarboxylation of histidine to histamine and carbon dioxide. It requires pyridoxal phosphate in animal tissues, but not in microorganisms. EC 126.96.36.199.Terfenadine: A selective histamine H1-receptor antagonist devoid of central nervous system depressant activity. The drug was used for ALLERGY but withdrawn due to causing LONG QT SYNDROME.Triprolidine: Histamine H1 antagonist used in allergic rhinitis; ASTHMA; and URTICARIA. It is a component of COUGH and COLD medicines. It may cause drowsiness.Astemizole: Antihistamine drug now withdrawn from the market in many countries because of rare but potentially fatal side effects.Histamine H3 Antagonists: Drugs that selectively bind to but do not activate HISTAMINE H3 RECEPTORS. They have been used to correct SLEEP WAKE DISORDERS and MEMORY DISORDERS.Cetirizine: A potent second-generation histamine H1 antagonist that is effective in the treatment of allergic rhinitis, chronic urticaria, and pollen-induced asthma. Unlike many traditional antihistamines, it does not cause drowsiness or anticholinergic side effects.Histamine N-Methyltransferase: An enzyme that catalyzes the transfer of a methyl group from S-adenosylmethionine to histamine, forming N-methylhistamine, the major metabolite of histamine in man. EC 188.8.131.52.Thiourea: A photographic fixative used also in the manufacture of resins. According to the Fourth Annual Report on Carcinogens (NTP 85-002, 1985), this substance may reasonably be anticipated to be a carcinogen (Merck Index, 9th ed). Many of its derivatives are ANTITHYROID AGENTS and/or FREE RADICAL SCAVENGERS.Burimamide: An antagonist of histamine that appears to block both H2 and H3 histamine receptors. It has been used in the treatment of ulcers.Cell Degranulation: The process of losing secretory granules (SECRETORY VESICLES). This occurs, for example, in mast cells, basophils, neutrophils, eosinophils, and platelets when secretory products are released from the granules by EXOCYTOSIS.Receptors, Antigen, T-Cell: Molecules on the surface of T-lymphocytes that recognize and combine with antigens. The receptors are non-covalently associated with a complex of several polypeptides collectively called CD3 antigens (ANTIGENS, CD3). Recognition of foreign antigen and the major histocompatibility complex is accomplished by a single heterodimeric antigen-receptor structure, composed of either alpha-beta (RECEPTORS, ANTIGEN, T-CELL, ALPHA-BETA) or gamma-delta (RECEPTORS, ANTIGEN, T-CELL, GAMMA-DELTA) chains.Antazoline: An antagonist of histamine H1 receptors.Ranitidine: A non-imidazole blocker of those histamine receptors that mediate gastric secretion (H2 receptors). It is used to treat gastrointestinal ulcers.p-Methoxy-N-methylphenethylamine: A potent mast cell degranulator. It is involved in histamine release.Histamine H1 Antagonists, Non-Sedating: A class of non-sedating drugs that bind to but do not activate histamine receptors (DRUG INVERSE AGONISM), thereby blocking the actions of histamine or histamine agonists. These antihistamines represent a heterogenous group of compounds with differing chemical structures, adverse effects, distribution, and metabolism. Compared to the early (first generation) antihistamines, these non-sedating antihistamines have greater receptor specificity, lower penetration of BLOOD-BRAIN BARRIER, and are less likely to cause drowsiness or psychomotor impairment.Ketotifen: A cycloheptathiophene blocker of histamine H1 receptors and release of inflammatory mediators. It has been proposed for the treatment of asthma, rhinitis, skin allergies, and anaphylaxis.Dibenzylchlorethamine: An alpha adrenergic antagonist.Famotidine: A competitive histamine H2-receptor antagonist. Its main pharmacodynamic effect is the inhibition of gastric secretion.Tryptases: A family of neutral serine proteases with TRYPSIN-like activity. Tryptases are primarily found in the SECRETORY GRANULES of MAST CELLS and are released during mast cell degranulation.Guinea Pigs: A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.Receptors, IgE: Specific molecular sites on the surface of B- and T-lymphocytes which combine with IgEs. Two subclasses exist: low affinity receptors (Fc epsilon RII) and high affinity receptors (Fc epsilon RI).Receptors, G-Protein-Coupled: The largest family of cell surface receptors involved in SIGNAL TRANSDUCTION. They share a common structure and signal through HETEROTRIMERIC G-PROTEINS.Sialadenitis: INFLAMMATION of salivary tissue (SALIVARY GLANDS), usually due to INFECTION or injuries.Chymases: A family of neutral serine proteases with CHYMOTRYPSIN-like activity. Chymases are primarily found in the SECRETORY GRANULES of MAST CELLS and are released during mast cell degranulation.Immunoglobulin E: An immunoglobulin associated with MAST CELLS. Overexpression has been associated with allergic hypersensitivity (HYPERSENSITIVITY, IMMEDIATE).Pheniramine: One of the HISTAMINE H1 ANTAGONISTS with little sedative action. It is used in treatment of hay fever, rhinitis, allergic dermatoses, and pruritus.Receptors, Antigen, T-Cell, alpha-beta: T-cell receptors composed of CD3-associated alpha and beta polypeptide chains and expressed primarily in CD4+ or CD8+ T-cells. Unlike immunoglobulins, the alpha-beta T-cell receptors recognize antigens only when presented in association with major histocompatibility (MHC) molecules.Cells, Cultured: Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.Pre-B Cell Receptors: Membrane proteins in precursor B-LYMPHOCYTES (pre-B Cells). They are composed of membrane-bound MU IMMUNOGLOBULIN HEAVY CHAINS in complex with SURROGATE LIGHT CHAINS instead of conventional IMMUNOGLOBULIN LIGHT CHAINS. Only successful rearrangement of the VDJ segments, at the Ig heavy chain gene locus (IMMUNOGLOBULIN HEAVY CHAIN GENES), will generate mu heavy chains that can pair with surrogate light chains. Thus formation of the pre-B cell receptors is an important checkpoint in the development of mature B cells.Promethazine: A phenothiazine derivative with histamine H1-blocking, antimuscarinic, and sedative properties. It is used as an antiallergic, in pruritus, for motion sickness and sedation, and also in animals.T-Lymphocytes: Lymphocytes responsible for cell-mediated immunity. Two types have been identified - cytotoxic (T-LYMPHOCYTES, CYTOTOXIC) and helper T-lymphocytes (T-LYMPHOCYTES, HELPER-INDUCER). They are formed when lymphocytes circulate through the THYMUS GLAND and differentiate to thymocytes. When exposed to an antigen, they divide rapidly and produce large numbers of new T cells sensitized to that antigen.Mustard Compounds: Strong alkylating and immunosuppressive agents whose biological activity is based on the presence of bis(2-chloroethyl)- groups. Although otherwise structurally diverse, the compounds have in common the capacity to contribute alkyl groups to DNA. They are generally highly toxic but include among their number many widely used and effective antineoplastic agents.Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.Mice, Inbred C57BLPruritus: An intense itching sensation that produces the urge to rub or scratch the skin to obtain relief.Anaphylaxis: An acute hypersensitivity reaction due to exposure to a previously encountered ANTIGEN. The reaction may include rapidly progressing URTICARIA, respiratory distress, vascular collapse, systemic SHOCK, and death.Hypersensitivity: Altered reactivity to an antigen, which can result in pathologic reactions upon subsequent exposure to that particular antigen.Clemastine: A histamine H1 antagonist used as the hydrogen fumarate in hay fever, rhinitis, allergic skin conditions, and pruritus. It causes drowsiness.Cromolyn Sodium: A chromone complex that acts by inhibiting the release of chemical mediators from sensitized mast cells. It is used in the prophylactic treatment of both allergic and exercise-induced asthma, but does not affect an established asthmatic attack.Signal Transduction: The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.Basophils: Granular leukocytes characterized by a relatively pale-staining, lobate nucleus and cytoplasm containing coarse dark-staining granules of variable size and stainable by basic dyes.Muscle, Smooth: Unstriated and unstriped muscle, one of the muscles of the internal organs, blood vessels, hair follicles, etc. Contractile elements are elongated, usually spindle-shaped cells with centrally located nuclei. Smooth muscle fibers are bound together into sheets or bundles by reticular fibers and frequently elastic nets are also abundant. (From Stedman, 25th ed)Mastocytosis: A heterogenous group of disorders characterized by the abnormal increase of MAST CELLS in only the skin (MASTOCYTOSIS, CUTANEOUS), in extracutaneous tissues involving multiple organs (MASTOCYTOSIS, SYSTEMIC), or in solid tumors (MASTOCYTOMA).Receptors, Antigen, B-Cell: IMMUNOGLOBULINS on the surface of B-LYMPHOCYTES. Their MESSENGER RNA contains an EXON with a membrane spanning sequence, producing immunoglobulins in the form of type I transmembrane proteins as opposed to secreted immunoglobulins (ANTIBODIES) which do not contain the membrane spanning segment.Piperidines: A family of hexahydropyridines.Skin: The outer covering of the body that protects it from the environment. It is composed of the DERMIS and the EPIDERMIS.Histamine Agents: Drugs used for their actions on histaminergic systems. Included are drugs that act at histamine receptors, affect the life cycle of histamine, or affect the state of histaminergic cells.Imidazoles: Compounds containing 1,3-diazole, a five membered aromatic ring containing two nitrogen atoms separated by one of the carbons. Chemically reduced ones include IMIDAZOLINES and IMIDAZOLIDINES. Distinguish from 1,2-diazole (PYRAZOLES).Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Cell Line: Established cell cultures that have the potential to propagate indefinitely.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Trachea: The cartilaginous and membranous tube descending from the larynx and branching into the right and left main bronchi.Lymphocyte Activation: Morphologic alteration of small B LYMPHOCYTES or T LYMPHOCYTES in culture into large blast-like cells able to synthesize DNA and RNA and to divide mitotically. It is induced by INTERLEUKINS; MITOGENS such as PHYTOHEMAGGLUTININS, and by specific ANTIGENS. It may also occur in vivo as in GRAFT REJECTION.Passive Cutaneous Anaphylaxis: An evanescent cutaneous reaction occurring when antibody is injected into a local area on the skin and antigen is subsequently injected intravenously along with a dye. The dye makes the rapidly occurring capillary dilatation and increased vascular permeability readily visible by leakage into the reaction site. PCA is a sensitive reaction for detecting very small quantities of antibodies and is also a method for studying the mechanisms of immediate hypersensitivity.Proto-Oncogene Proteins c-kit: A protein-tyrosine kinase receptor that is specific for STEM CELL FACTOR. This interaction is crucial for the development of hematopoietic, gonadal, and pigment stem cells. Genetic mutations that disrupt the expression of PROTO-ONCOGENE PROTEINS C-KIT are associated with PIEBALDISM, while overexpression or constitutive activation of the c-kit protein-tyrosine kinase is associated with tumorigenesis.Antigens, CD3: Complex of at least five membrane-bound polypeptides in mature T-lymphocytes that are non-covalently associated with one another and with the T-cell receptor (RECEPTORS, ANTIGEN, T-CELL). The CD3 complex includes the gamma, delta, epsilon, zeta, and eta chains (subunits). When antigen binds to the T-cell receptor, the CD3 complex transduces the activating signals to the cytoplasm of the T-cell. The CD3 gamma and delta chains (subunits) are separate from and not related to the gamma/delta chains of the T-cell receptor (RECEPTORS, ANTIGEN, T-CELL, GAMMA-DELTA).Cyclic AMP: An adenine nucleotide containing one phosphate group which is esterified to both the 3'- and 5'-positions of the sugar moiety. It is a second messenger and a key intracellular regulator, functioning as a mediator of activity for a number of hormones, including epinephrine, glucagon, and ACTH.Peritoneal Cavity: The space enclosed by the peritoneum. It is divided into two portions, the greater sac and the lesser sac or omental bursa, which lies behind the STOMACH. The two sacs are connected by the foramen of Winslow, or epiploic foramen.Serine Endopeptidases: Any member of the group of ENDOPEPTIDASES containing at the active site a serine residue involved in catalysis.RNA, Messenger: RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.Mastocytosis, Systemic: A group of disorders caused by the abnormal proliferation of MAST CELLS in a variety of extracutaneous tissues including bone marrow, liver, spleen, lymph nodes, and gastrointestinal tract. Systemic mastocytosis is commonly seen in adults. These diseases are categorized on the basis of clinical features, pathologic findings, and prognosis.Muscle Contraction: A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments.Atropine: An alkaloid, originally from Atropa belladonna, but found in other plants, mainly SOLANACEAE. Hyoscyamine is the 3(S)-endo isomer of atropine.Stem Cell Factor: A hematopoietic growth factor and the ligand of the cell surface c-kit protein (PROTO-ONCOGENE PROTEINS C-KIT). It is expressed during embryogenesis and is a growth factor for a number of cell types including the MAST CELLS and the MELANOCYTES in addition to the HEMATOPOIETIC STEM CELLS.Drug Interactions: The action of a drug that may affect the activity, metabolism, or toxicity of another drug.Receptors, Antigen, T-Cell, gamma-delta: T-cell receptors composed of CD3-associated gamma and delta polypeptide chains and expressed primarily in CD4-/CD8- T-cells. The receptors appear to be preferentially located in epithelial sites and probably play a role in the recognition of bacterial antigens. The T-cell receptor gamma/delta chains are separate and not related to the gamma and delta chains which are subunits of CD3 (see ANTIGENS, CD3).Ileum: The distal and narrowest portion of the SMALL INTESTINE, between the JEJUNUM and the ILEOCECAL VALVE of the LARGE INTESTINE.Calcium: A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.Mice, Transgenic: Laboratory mice that have been produced from a genetically manipulated EGG or EMBRYO, MAMMALIAN.Receptors, Drug: Proteins that bind specific drugs with high affinity and trigger intracellular changes influencing the behavior of cells. Drug receptors are generally thought to be receptors for some endogenous substance not otherwise specified.Thymus Gland: A single, unpaired primary lymphoid organ situated in the MEDIASTINUM, extending superiorly into the neck to the lower edge of the THYROID GLAND and inferiorly to the fourth costal cartilage. It is necessary for normal development of immunologic function early in life. By puberty, it begins to involute and much of the tissue is replaced by fat.Mice, Inbred BALB CReceptors, Natural Killer Cell: Receptors that are specifically found on the surface of NATURAL KILLER CELLS. They play an important role in regulating the cellular component of INNATE IMMUNITY.Cytoplasmic Granules: Condensed areas of cellular material that may be bounded by a membrane.Gene Rearrangement, T-Lymphocyte: Ordered rearrangement of T-cell variable gene regions coding for the antigen receptors.Antigens: Substances that are recognized by the immune system and induce an immune reaction.Dogs: The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)Mice, Knockout: Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.beta-N-Acetylhexosaminidases: A hexosaminidase specific for non-reducing N-acetyl-D-hexosamine residues in N-acetyl-beta-D-hexosaminides. It acts on GLUCOSIDES; GALACTOSIDES; and several OLIGOSACCHARIDES. Two specific mammalian isoenzymes of beta-N-acetylhexoaminidase are referred to as HEXOSAMINIDASE A and HEXOSAMINIDASE B. Deficiency of the type A isoenzyme causes TAY-SACHS DISEASE, while deficiency of both A and B isozymes causes SANDHOFF DISEASE. The enzyme has also been used as a tumor marker to distinguish between malignant and benign disease.Flow Cytometry: Technique using an instrument system for making, processing, and displaying one or more measurements on individual cells obtained from a cell suspension. Cells are usually stained with one or more fluorescent dyes specific to cell components of interest, e.g., DNA, and fluorescence of each cell is measured as it rapidly transverses the excitation beam (laser or mercury arc lamp). Fluorescence provides a quantitative measure of various biochemical and biophysical properties of the cell, as well as a basis for cell sorting. Other measurable optical parameters include light absorption and light scattering, the latter being applicable to the measurement of cell size, shape, density, granularity, and stain uptake.Anti-Allergic Agents: Agents that are used to treat allergic reactions. Most of these drugs act by preventing the release of inflammatory mediators or inhibiting the actions of released mediators on their target cells. (From AMA Drug Evaluations Annual, 1994, p475)ThiazolesTime Factors: Elements of limited time intervals, contributing to particular results or situations.Genes, T-Cell Receptor beta: DNA sequences encoding the beta chain of the T-cell receptor. The genomic organization of the TcR beta genes is essentially the same in all species and is similar to the organization of Ig genes.Leukemia, Mast-Cell: A form of systemic mastocytosis (MASTOCYTOSIS, SYSTEMIC) characterized by the presence of large numbers of tissue MAST CELLS in the peripheral blood without skin lesions. It is a high-grade LEUKEMIA disease with bone marrow smear of >20% MAST CELLS, multi-organ failure and a short survival.Cell Count: The number of CELLS of a specific kind, usually measured per unit volume or area of sample.Radioligand Assay: Quantitative determination of receptor (binding) proteins in body fluids or tissue using radioactively labeled binding reagents (e.g., antibodies, intracellular receptors, plasma binders).Receptor-CD3 Complex, Antigen, T-Cell: Molecule composed of the non-covalent association of the T-cell antigen receptor (RECEPTORS, ANTIGEN, T-CELL) with the CD3 complex (ANTIGENS, CD3). This association is required for the surface expression and function of both components. The molecule consists of up to seven chains: either the alpha/beta or gamma/delta chains of the T-cell receptor, and four or five chains in the CD3 complex.Carboxypeptidases A: Carboxypeptidases that are primarily found the DIGESTIVE SYSTEM that catalyze the release of C-terminal amino acids. Carboxypeptidases A have little or no activity for hydrolysis of C-terminal ASPARTIC ACID; GLUTAMIC ACID; ARGININE; LYSINE; or PROLINE. This enzyme requires ZINC as a cofactor and was formerly listed as EC 184.108.40.206 and EC 220.127.116.11.B-Lymphocytes: Lymphoid cells concerned with humoral immunity. They are short-lived cells resembling bursa-derived lymphocytes of birds in their production of immunoglobulin upon appropriate stimulation.Inositol Phosphates: Phosphoric acid esters of inositol. They include mono- and polyphosphoric acid esters, with the exception of inositol hexaphosphate which is PHYTIC ACID.Clone Cells: A group of genetically identical cells all descended from a single common ancestral cell by mitosis in eukaryotes or by binary fission in prokaryotes. Clone cells also include populations of recombinant DNA molecules all carrying the same inserted sequence. (From King & Stansfield, Dictionary of Genetics, 4th ed)Cell Membrane: The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.U937 Cells: A human cell line established from a diffuse histiocytic lymphoma (HISTIOCYTIC LYMPHOMA, DIFFUSE) and displaying many monocytic characteristics. It serves as an in vitro model for MONOCYTE and MACROPHAGE differentiation.Gene Expression: The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.Mice, Mutant Strains: Mice bearing mutant genes which are phenotypically expressed in the animals.Antigens, CD8: Differentiation antigens found on thymocytes and on cytotoxic and suppressor T-lymphocytes. CD8 antigens are members of the immunoglobulin supergene family and are associative recognition elements in MHC (Major Histocompatibility Complex) Class I-restricted interactions.Complementarity Determining Regions: Three regions (CDR1; CDR2 and CDR3) of amino acid sequence in the IMMUNOGLOBULIN VARIABLE REGION that are highly divergent. Together the CDRs from the light and heavy immunoglobulin chains form a surface that is complementary to the antigen. These regions are also present in other members of the immunoglobulin superfamily, for example, T-cell receptors (RECEPTORS, ANTIGEN, T-CELL).Thioxanthenes: Compounds with three aromatic rings in linear arrangement with a SULFUR in the center ring.Kinetics: The rate dynamics in chemical or physical systems.Gene Rearrangement, beta-Chain T-Cell Antigen Receptor: Ordered rearrangement of T-cell variable gene regions coding for the beta-chain of antigen receptors.Pyridines: Compounds with a six membered aromatic ring containing NITROGEN. The saturated version is PIPERIDINES.Salivary Glands: Glands that secrete SALIVA in the MOUTH. There are three pairs of salivary glands (PAROTID GLAND; SUBLINGUAL GLAND; SUBMANDIBULAR GLAND).Antigens, CD: Differentiation antigens residing on mammalian leukocytes. CD stands for cluster of differentiation, which refers to groups of monoclonal antibodies that show similar reactivity with certain subpopulations of antigens of a particular lineage or differentiation stage. The subpopulations of antigens are also known by the same CD designation.Cell Differentiation: Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.Jurkat Cells: A CELL LINE derived from human T-CELL LEUKEMIA and used to determine the mechanism of differential susceptibility to anti-cancer drugs and radiation.Receptors, Immunologic: Cell surface molecules on cells of the immune system that specifically bind surface molecules or messenger molecules and trigger changes in the behavior of cells. Although these receptors were first identified in the immune system, many have important functions elsewhere.Cytokines: Non-antibody proteins secreted by inflammatory leukocytes and some non-leukocytic cells, that act as intercellular mediators. They differ from classical hormones in that they are produced by a number of tissue or cell types rather than by specialized glands. They generally act locally in a paracrine or autocrine rather than endocrine manner.ZAP-70 Protein-Tyrosine Kinase: A protein tyrosine kinase that is required for T-CELL development and T-CELL ANTIGEN RECEPTOR function.Genes, T-Cell Receptor alpha: DNA sequences encoding the alpha chain of the T-cell receptor. The genomic organization of the TcR alpha genes is essentially the same in all species and is similar to the organization of Ig genes.Rabbits: The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Cats: The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)CD4-Positive T-Lymphocytes: A critical subpopulation of T-lymphocytes involved in the induction of most immunological functions. The HIV virus has selective tropism for the T4 cell which expresses the CD4 phenotypic marker, a receptor for HIV. In fact, the key element in the profound immunosuppression seen in HIV infection is the depletion of this subset of T-lymphocytes.
During an attack, blood tests for tryptase or histamine (released from mast cells) might be useful in diagnosing anaphylaxis ... or anaphylactoid reactions are a type of anaphylaxis that does not involve an allergic reaction but is due to direct mast cell ... Antigen-bound IgE then activates FcεRI receptors on mast cells and basophils. This leads to the release of inflammatory ... The coronary spasm is related to the presence of histamine-releasing cells in the heart. While a fast heart rate caused by low ...
... acts as a selective antagonist of the histamine H1 receptor, thus stabilizing mast cells and inhibiting histamine ... "Topical antihistamines and mast cell stabilisers for treating seasonal and perennial allergic conjunctivitis". Cochrane ... Olopatadine is an antihistamine (as well as anticholinergic and mast cell stabilizer), sold as a prescription eye drop ... It is used to treat itching associated with allergic conjunctivitis (eye allergies). A steroid-free nasal spray formulation is ...
It supresses allergic reactions by binding to FcεRI receptor in mast cells, thereby inhibiting production of histamines. It is ... Proxicromil is a mast-cell stabilizer that prevents degranulation and release of mediators such as histamine from mast cells. ... Mast cells are a type of white blood cells that function in the immune and neuro-immune system. Allergic reactions or responses ... Dietsch, Hinrichs, G. N., D.J. (1989). "The role of mast cells in the elicitation of experimental allergic encephalomyelitis". ...
During an attack, blood tests for tryptase or histamine (released from mast cells) might be useful in diagnosing anaphylaxis ... or anaphylactoid reactions are a type of anaphylaxis that does not involve an allergic reaction but is due to direct mast cell ... Antigen-bound IgE then activates FcεRI receptors on mast cells and basophils. This leads to the release of inflammatory ... Non-immunologic mechanisms involve substances that directly cause the degranulation of mast cells and basophils. These include ...
... antigens can cause systemic anaphylaxis in mice through classic pathway by cross-linking IgE bound to the mast cell receptor Fc ... IgG affinity to Fc receptors on phagocytic cells is specific to individual species from which the antibody comes as well as the ... IgG are also involved in the regulation of allergic reactions. According to Finkelman, there are two pathways of systemic ... εRI, stimulating the release of both histamine and platelet activating factor (PAF). In the alternative pathway antigens form ...
Stem cell factor
Mast cells are the only terminally differentiated hematopoietic cells that express the c-Kit receptor. Mice with SCF or c-Kit ... It also promotes the release of histamine and tryptase, which are involved in the allergic response. The presence of both ... SCF binds to the c-KIT receptor (CD 117), a receptor tyrosine kinase. c-Kit is expressed in HSCs, mast cells, melanocytes, and ... of the normal levels of mast cells. Conversely, the injection of SCF increases mast cell numbers near the site of injection by ...
IgE then binds to IgE receptors on the surface of mast cells. Then, mast cells release histamine, which then leads to the ... Histamine also binds to H1 and H2 receptors of the conjunctival vasculature and causes vasodilatation. Mast cell-derived ... When histamine is released from mast cells, it binds to H1 receptors on nerve endings and causes the ocular symptom of itching ... Mast cell intermediaries cause an allergic inflammation and symptoms through the activation of inflammatory cells. ...
IgE primes the IgE-mediated allergic response by binding to Fc receptors found on the surface of mast cells and basophils. Fc ... mast cell stabilizers, which inhibit the degranulation of mast cells that is normally triggered by IgE-binding at FcεRI. Long- ... Ishizaka,, Teruko; Ishizaka, Kimishige; Johansson, S. Gunnar O.; Bennich, Hans (April 1, 1969). "Histamine Release from Human ... There are two types of Fcε receptors: FcεRI (type I Fcε receptor), the high-affinity IgE receptor FcεRII (type II Fcε receptor ...
3 - FcεRI receptor. 4 - preformed mediators (histamine, proteases, chemokines, heparin). 5 - granules. 6 - mast cell. 7 - newly ... Allergic reactions are hyperactive responses of the immune system to generally innocuous substances. When immune cells ... a kind of Fc receptor called FcεRI) on the surface of other kinds of immune cells called mast cells and basophils, which are ... Activated mast cells and basophils undergo a process called degranulation, during which they release histamine and other ...
Pawankar R (February 2001). "Mast cells as orchestrators of the allergic reaction: the IgE-IgE receptor mast cell network". ... The most famous mediator is histamine, which results in the five symptoms of inflammation: heat, swelling, pain, redness and ... mast cells, and basophils. As a result of its cellular distribution, this receptor plays a major role in controlling allergic ... Siraganian RP (December 2003). "Mast cell signal transduction from the high-affinity IgE receptor". Curr. Opin. Immunol. 15 (6 ...
... set of mast cell mediators is released through degranulation following the activation of cell surface receptors on mast cells. ... and allergic rhinitis and allergic conjunctivitis. Antihistamine drugs act by blocking histamine action on nerve endings. ... Other neoplastic disorders associated with mast cells include mast cell sarcoma and mast cell leukemia. Mast cell activation ... connective tissue-type mast cells and mucosal mast cells. The activities of the latter are dependent on T-cells. Mast cells are ...
MCT mast cells found in the mucosa are stabilised." Nedocromil is another mast cell stabilizer that also works in controlling ... This drug prevents the release of inflammatory chemicals such as histamine from mast cells. Because of their convenience (and ... "Topical antihistamines and mast cell stabilisers for treating seasonal and perennial allergic conjunctivitis". Cochrane ... exaggerated neuronal reflexes triggered by stimulation of irritant receptors on sensory nerve endings (e.g. exercise-induced ...
The high affinity IgE receptor plays a central role in allergic disease, coupling allergen and mast cell to initiate the ... "The high-affinity IgE receptor (FcepsilonRI): a critical regulator of airway smooth muscle cells?". Am. J. Physiol. Lung Cell ... occurs that brings about the release of histamine and proteases from the granules in the cytoplasm of the mast cell and leads ... Le Coniat M, Kinet JP, Berger R (1990). "The human genes for the alpha and gamma subunits of the mast cell receptor for ...
Receptors. IgE primes the IgE-mediated allergic response by binding to Fc receptors found on the surface of mast cells ... histamine, proteases, chemokines, heparin); 5 - granules; 6 - mast cell; 7 - newly formed mediators (prostaglandins, ... mast cell stabilizers, which inhibit the degranulation of mast cells that is normally triggered by IgE-binding at FcεRI. Long- ... IgE can upregulate the expression of both types of Fcε receptors. FcεRI is expressed on mast cells, basophils, and the antigen- ...
Activated mast cells and basophils undergo a process called degranulation, during which they release histamine and other ... circulates in the blood and binds to IgE-specific receptors on the surface of other kinds of immune cells called mast cells and ... Allergic responses can be divided into two phases: an acute response that occurs immediately after exposure to an allergen, ... also described as cell-mediated allergy. Confirmation is by double-blind, placebo-controlled food challenges, conducted by an ...
Activated mast cells and basophils undergo a process called degranulation, during which they release histamine and other ... circulates in the blood and binds to IgE-specific receptors on the surface of other kinds of immune cells called mast cells and ... Allergic responses can be divided into two phases: an acute response that occurs immediately after exposure to an allergen, ... also described as cell-mediated allergy. SPT and sIgE have sensitivities of 55% and 83% respectively, and specificities of 68% ...
H1-antihistamines work by binding to histamine H1 receptors in mast cells, smooth muscle, and endothelium in the body as well ... Clinically, H1-antihistamines are used to treat allergic reactions and mast cell-related disorders. Sedation is a common side ... Normally, histamine binds to the H1 receptor and heightens the receptor's activity; the receptor antagonists work by binding to ... Mast cell stabilizers are drugs which prevent mast cell degranulation. cromolyn sodium Nedocromil β-agonists Currently most ...
... and then to a receptor on mast cells or basophils where it triggers the release of inflammatory chemicals such as histamine. ... mast cell stabilizers, and antileukotriene agents are common treatments of allergic diseases. Anti-cholinergics, decongestants ... a kind of Fc receptor called FcεRI) on the surface of other kinds of immune cells called mast cells and basophils, which are ... Activated mast cells and basophils undergo a process called degranulation, during which they release histamine and other ...
... the FcεRI receptors on basophils, mast cells, and dendritic cells are gradually down-regulated with somewhat different kinetics ... providing the fundamental mechanism for omalizumab's effects on various allergic and non-allergic diseases involving mast cell ... such as histamine, leukotrienes, tryptase, inflammatory cytokines, and others, causing various allergic symptoms/diseases. The ... series of papers have shown that IgE potentiates the activities of mast cells and omalizumab can function as a mast cell- ...
For example, IgE is responsible for an allergic response consisting of mast cell degranulation and histamine release. IgE's Fab ... Those cells that recognize coated pathogens have Fc receptors, which, as the name suggests, interact with the Fc region of IgA ... Williams, CM; Galli, SJ (May 2000). "The diverse potential effector and immunoregulatory roles of mast cells in allergic ... In humans, the cell surface is bare around the B cell receptors for several hundred nanometers, which further isolates the BCRs ...
... from the mast cell or basophil. Once released, the histamine can react with local or widespread tissues through histamine ... at the histamine H1-receptor. In type I hypersensitivity allergic reactions, an allergen (a type of antigen) interacts with and ... cross-links surface IgE antibodies on mast cells and basophils. Once the mast cell-antibody-antigen complex is formed, a ... These agents also commonly have action at α-adrenergic receptors and/or 5-HT receptors. This lack of receptor selectivity is ...
Activated mast cells and basophils undergo a process called degranulation, during which they release histamine and other ... circulates in the blood and binds to IgE-specific receptors on the surface of other kinds of immune cells called mast cells and ... including allergic eosinophilic esophagitis. Egg whites, which are potentially histamine liberators, also provoke a nonallergic ... The measles and mumps parts of the "MMR vaccine" (for measles, mumps, and rubella) are cultured on chick embryo cell culture ...
Accordingly, these cells contain the body's highest concentrations of histamine granules. No-mast cell histamine is also found ... For example, diphenhydramine (Benadryl™), targets and inhibits the H1 histamine receptor to relieve symptoms of allergic ... H3 controls histamine turnover by feedback inhibition of histamine synthesis and release. Finally, H4 plays roles in mast cell ... 2008). "Expression of non-mast cell histidine decarboxylase in tumor-associated microvessels in human esophageal squamous cell ...
Acute severe asthma
The IgE antibody attaches to surface receptors on airway mucosal mast cells. One important question is whether atopic ... mast cells, lymphocytes, and neutrophils during the late-phase (or chronic) reaction. The simple explanation for allergic ... These mediators include histamine; leukotrienes C4, D4, and E4; and a host of cytokines. Together, these mediators cause ... bronchial smooth muscle constriction, vascular leakage, inflammatory cell recruitment (with further mediator release), and ...
Symptoms are thought to be the result of histamine being released by mast cells on the surface of the skin. Due to the lack of ... systemic mast cell proliferation). Dermographism can be treated by substances (i.e. an antihistamine) which prevent histamine ... In rare cases, allergy tests may uncover substances the patient is allergic to. While cromoglycate, which prevents histamine ... These may need to be given as a combination of H1 antagonists, or possibly with an H2-receptor antagonist such as cimetidine. ...
Histamine and other proinflammatory substances are released from mast cells in the skin and tissues in response to the binding ... of allergen-bound IgE antibodies to high-affinity cell surface receptors. Basophils and other inflammatory cells are also seen ... Whether the trigger is allergic or not, a complex release of inflammatory mediators, including histamine from cutaneous mast ... inhibit cell responsiveness to mast cell products and inhibit T cell activity. They are preferred by some experts to treat ...
The most important pathophysiologic mechanism of mast cell and basophil histamine release is immunologic. These cells, if ... allergic rhinitis) Histamine intolerance Histamine receptor antagonist Red wine headache Scombroid food poisoning Histamine ... Most histamine in the body is generated in granules in mast cells and in white blood cells (leukocytes) called basophils. Mast ... release histamine that stimulates nearby parietal cells by binding to the apical H2 receptor. Stimulation of the parietal cell ...
Prostaglandin EP3 receptor
... stimulates mouse and human mast cells to release histamine by an EP3-dependent mechanism. Furthermore, EP3-deficient mice fail ... EP3 receptor-deficient mice and/or wild type mice treated with an EP3 receptor agonist are similarly protected from allergic ... a mouse lung cancer cell line, is suppressed in EP33 receptor deficient mice. This effect was associated with a reduction in ... Eicosanoid receptor Prostaglandin E2 receptor 1 (EP1) Prostaglandin E2 receptor 2 (EP2) Prostaglandin E2 receptor 4 (EP4) ...
Allergic hivesEdit. Histamine and other proinflammatory substances are released from mast cells in the skin and tissues in ... response to the binding of allergen-bound IgE antibodies to high-affinity cell surface receptors. Basophils and other ... Leukotriene-receptor antagonistsEdit. Leukotrienes are released from mast cells along with histamine. The medications, ... inhibit cell responsiveness to mast cell products and inhibit T cell activity. They are preferred by some experts to treat ...
... by mast cells following the cross-linking of allergen specific IgE molecules bound to mast cell FcεRI receptors. These ... The reaction is caused by the release of histamine and mast cell granule proteins by a process called degranulation, as well as ... cell isotype switching to IgE which will bind to the mast cell FcεRI receptors and prime the individual for further allergic ... which develops 8-12 hours and is mediated by mast cells) should not be confused with delayed hypersensitivity Type IV allergic ...
Ketotifen fumarate CAS#: 34580-14-8
... the related pharmacological studies of ketotifen fumarate have confirmed that it can inhibit mast cell /basophil cells to ... by both a strong antagonism effect on histamine H1 receptor and inhibitory effect of the release of the mediator of allergic ... It can inhibit the release various kinds of mediators of mast cells, basophils and macrophages, including the release of slow ... UsesKetotifen, C19H19NOS, is also a piperidine derivative; like oxatomide, it has mast cell stabilizing actions besides its ...
Ketotifen Fumarate 2mg/ml , 60ml
Ketotifen fumarate is an H1 antihistamine and mast cell stabilizer used in treatment of allergies and asthma orally and for ... allergic symptoms and allergic conjunctivitis in ophthalmic form. Ketotifen is also known for its effect of up-regulating the ... Whether this effect is secondary to the mast cell stabilising properties of ketotifen or H(1) receptor antagonism remains to be ... The number of mast cells in rectal biopsies and spontaneous release of tryptase were lower in patients with IBS than in healthy ...
Histamine H4 Receptor Mediates Chemotaxis and Calcium Mobilization of Mast Cells | Journal of Pharmacology and Experimental...
Migration of mast cells may also play a role in allergic rhinitis and allergy where increases in mast cell number are found ( ... Histamine induces cyclic AMP in mast cells through H2 receptors, but not H4 receptors. Mast cells of H3R-/- mice were activated ... Mast cells are important effector cells in allergic diseases. Mast cells bind IgE with IgE receptor, and subsequent contact ... Histamine induces calcium mobilization in mast cells through H4 receptors. A, histamine induces calcium mobilization in mast ...
Talk to Me about Mast Cells - Lyme Disease
I would like to hear from people trying to heal from Lyme who also have mast cell activation issues. In your experience, how ... Its basically an allergic reaction. Antihistamines dont target the same receptors that are affected - mast cells. You are ... I would like to hear from people trying to heal from Lyme who also have mast cell activation issues. In your experience, how ... Low histamine diet works best. I would get itchy, skin tingling sensations, and of course the inflammation leads to weight gain ...
Identification of a mast-cell-specific receptor crucial for pseudo-allergic drug reactions. - PubMed - NCBI
Mast cells are primary effectors in allergic reactions, and may have important roles in disease by secreting histamine and ... Identification of a mast-cell-specific receptor crucial for pseudo-allergic drug reactions.. McNeil BD1, Pundir P2, Meeker S3, ... Identification of a mast cell specific receptor crucial for pseudo-allergic drug reactions ... Identification of a mast cell specific receptor crucial for pseudo-allergic drug reactions ...
Epinastine Hydrochloride Monograph for Professionals - Drugs.com
Relatively selective histamine H1-receptor antagonist1 with mast-cell stabilizing properties.2 ... Inhibits the release of mediators (e.g., histamine) from cells involved in hypersensitivity reactions (e.g., mast cells).1 2 ... Allergic Conjunctivitis. Prevention of ocular itching associated with allergic conjunctivitis.1. Epinastine Hydrochloride ... Histamine H1-receptor Antagonists. Chemical Name: 3-Amino-9,13b-dihydro-1H-dibenz[c,f]imidazo[1,5-a]azepine. Molecular Formula: ...
Parvovirus B19 Infection Medication: Antipyretic agents, Immunologic effectors, Antihistamines
These agents decrease or prevent allergic symptoms caused by histamine receptors from mast cells. ... Case report: aplastic crisis in sickle cell disorders: bone marrow necrosis and human parvovirus infection. Am J Med Sci. 1988 ... blocks Fc receptors on macrophages; suppresses inducer T and B cells and augments suppressor T cells; blocks complement cascade ... Competitively blocks histamine from binding to H1 receptors. As a result of CNS penetration, diphenhydramine frequently causes ...
12.2 - Antibodies and immunity Flashcards by Hannah Chorley | Brainscape
... allergen molecules bind to the IgE antibodies attached to the mast cell. 6) Mast cell releases histamine. 7) Inflammatory ... 4) Antibodies bind to receptors on mast cells. 5) On the next encounter with allergen, ... Pathogens are immobilised when clumped together so prevents them from entering cells, making phagocytosis easier ... Outline the stages of an allergic reaction 1) Initial contact with the allergen. 2) Primary immune response triggered. 3) IgE ...
Gs-Coupled Adenosine Receptors Differentially Limit Antigen-Induced Mast Cell Activation | Journal of Pharmacology and...
1987) Inhibition of IgE-dependent histamine release from human dispersed lung mast cells by anti-allergic drugs and salbutamol ... Many of these mediators, such as histamine, are released by mast cells. Targeting pathways that limit antigen-induced mast cell ... In addition to β-adrenergic receptors, mast cells express other Gs-coupled receptors, including the A2 adenosine receptors A2A ... 2000) Activation of adenosine A2 alpha receptors inhibits mast cell degranulation and mast cell-dependent vasoconstriction. ...
Anaphylaxis - Wikipedia
During an attack, blood tests for tryptase or histamine (released from mast cells) might be useful in diagnosing anaphylaxis ... or anaphylactoid reactions are a type of anaphylaxis that does not involve an allergic reaction but is due to direct mast cell ... Antigen-bound IgE then activates FcεRI receptors on mast cells and basophils. This leads to the release of inflammatory ... Non-immunologic mechanisms involve substances that directly cause the degranulation of mast cells and basophils. These include ...
Are the anti-allergic actions of theophylline due to antagonism at the adenosine receptor | SpringerLink
Adenosine potentiated anaphylactic histamine release from isolated rat mast cells in a dose-dependent manner between 10−8 and ... Adenosine Mast Cell Histamine Theophylline Phosphodiesterase This is a preview of subscription content, log in to check access ... Adenosine potentiated anaphylactic histamine release from isolated rat mast cells in a dose-dependent manner between 10−8 and ... A. Sydbom andT. Karlsson,Relationship Between Serum IgE Level and Anaphylactic Histamine Release from Isolated Rat Mast Cells, ...
Olopatadine - Wikipedia
Olopatadine acts as a selective antagonist of the histamine H1 receptor, thus stabilizing mast cells and inhibiting histamine ... "Topical antihistamines and mast cell stabilisers for treating seasonal and perennial allergic conjunctivitis". Cochrane ... Olopatadine is an antihistamine (as well as anticholinergic and mast cell stabilizer), sold as a prescription eye drop ... It is used to treat itching associated with allergic conjunctivitis (eye allergies). A steroid-free nasal spray formulation is ...
Anaphylaxis - Wikipedia
During an attack, blood tests for tryptase or histamine (released from mast cells) might be useful in diagnosing anaphylaxis ... or anaphylactoid reactions are a type of anaphylaxis that does not involve an allergic reaction but is due to direct mast cell ... Antigen-bound IgE then activates FcεRI receptors on mast cells and basophils. This leads to the release of inflammatory ... The coronary spasm is related to the presence of histamine-releasing cells in the heart. While a fast heart rate caused by low ...
Google Answers: High Histamine Levels
Histamine is released from histamine-storing cells (mast cells) and then attaches to other cells that have receptors for ... The attachment of the histamine to the receptors causes the cell to be activated, releasing other chemicals which produce the ... In extreme cases, histamine levels in someone who is allergic to a bee sting or a particular food like strawberries can be ... Benadryl and other over the counter anti-histamines are often used when histamine is released by mast cells (specialized white ...
Inflammatory Mediators Flashcards by ashley f | Brainscape
gastic acid secretion (by H2 receptors on gastric parietal cells). -gastric carcinoid tumors (proliferation of mast cells and ... function of endogenous histamine -allergic hypersensitivity response. - ... pharmacologic effect of H2 receptor -vascular/smooth muscle. -gastric parietal cell. -cardiac. -some CNS ... REVERSIBLE, competitive inhibitors of the H1 receptor (act like an inverse agonist) ...
Xinzhong Dong Reports in Nature the Identification of a New Mast Cell Allergy Receptor - The Solomon H Snyder Department of...
Mast cells are primary effectors in allergic reactions, and may have important roles in disease by secreting histamine and ... This receptor is exclusively found in a type of immune cells called mast cells. Once the receptor is triggered, it causes mast ... Identification of a mast-cell-specific receptor crucial for pseudo-allergic drug reactions. McNeil et al, Nature (2014) doi: ... reports in Nature the identification of a new receptor on mast cells linked to drug-induced allergic reactions. Many clinical ...
DailyMed - STANDARDIZED MITE D FARINAE- dermatophagoides farinae injection, solution STANDARDIZED MITE D PTERONYSSINUS-...
IgE antibodies bind to surface receptors on mast cells and basophils.. When antigens gain access to the immune system they ... a decrease in histamine release to specific allergen and an increase in suppressor cell population to specific allergen. These ... The allergic state is initiated by an immune response inducing B cells to produce IgE antibodies to specific allergens. ... The reacting antigen to the surface bound IgE stimulates a number of chemical mediators to be released from the mast cells and ...
Stem cell factor - wikidoc
Expression in mast cells. Mast cells are the only terminally differentiated hematopoietic cells that express the c-Kit receptor ... It also promotes the release of histamine and tryptase, which are involved in the allergic response. ... SCF binds to the c-KIT receptor (CD 117), a receptor tyrosine kinase. c-Kit is expressed in HSCs, mast cells, melanocytes, ... of the normal levels of mast cells. Conversely, the injection of SCF increases mast cell numbers near the site of injection by ...
Cytotoxic anaphylaxis | definition of cytotoxic anaphylaxis by Medical dictionary
Release is a consequence of the binding of IgE antibodies to Fc receptors on the surface of particularly mast cells and ... complement-dependent hypersensitivity to foreign cells or to alterations of cell-surface antigens that is mediated by ... an unusual or exaggerated allergic reaction of an animal to foreign protein or other substances. Anaphylaxis is an immediate or ... antibody-mediated hypersensitivity reaction (type I) produced by the release of vasoactive agents such as histamine and ...
Anaphalactic shock | definition of Anaphalactic shock by Medical dictionary
... they cause the mast cell to release histamine and other chemicals, which spill out onto neighboring cells. ... Release is a consequence of the binding of IgE antibodies to Fc receptors on the surface of particularly mast cells and ... Like the majority of other allergic reactions, anaphylaxis is caused by the release of histamine and other chemicals from mast ... Mast cells are a type of white blood cell and they are found in large numbers in the tissues that regulate exchange with the ...
Mediators, Receptors, and Signalling Pathways in the Anti-Inflammatory and Antihyperalgesic Effects of Acupuncture
Histamine released by mast cells activates histamine 1 receptor (H1R) producing signalling via the phospholipase A2/ ... modulating transient receptor potential vallinoid (TRPV1), a G-protein coupled receptor which plays a central role in allergic ... STAT 6 and NFκB are transcription factors which play an essential role in Th2 cell differentiation . Inhibition of STAT 6 ... 4. Complex Cross Talk between Receptors. Chemokine receptors, opioid receptors and TRPV1 receptors have been reported to ...
Search Results For Health And Wellness: Replenishing Results found: 13
Also, it is believed that pycnogenol interferes with the effects of histamine via its receptors, and acts on mast cells ... of the cells. ATP is crucial in maintaining the integrity and function of every cell, which is necessary for day- to-day health ... This is the reason why it is widely accepted as a viable treatment option for asthma, multiple sclerosis, allergic rhinitis, ... It is thought that because the components of rose hip oil are so similar to those of skin cell membranes, that is why this oil ...
Pediatric Allergic Rhinitis: Practice Essentials, Background, Pathophysiology
Some patients find allergic rhinitis to be just as debilitating and intrusive as severe asthma. ... Although allergic rhinitis (AR) is a common disease, the impact on daily life cannot be underestimated. ... For example, tree pollen allergen binds to IgE antibodies that are attached to a mast cell via Fcε receptor. When 2 IgE ... This cross-linking causes mast cells to degranulate, releasing various mediators. The best-known mediators are histamine, ...
What is the role of immune hypersensitivity in the pathophysiology of acute urticaria (hives)?
... the H1 and H2 receptors, which are present on many cell types. The activation of the H1 histamine receptors on endothelial and ... Histamine is the ligand for 2 membrane-bound receptors, ... bind and cross-link Fc receptors on the surface of mast cells ... Allergic reactions due to ibuprofen in children. Pediatr Dermatol. 2001 Jan-Feb. 18(1):66-7. [Medline]. ... Histamine is the ligand for 2 membrane-bound receptors, the H1 and H2 receptors, which are present on many cell types. The ...
Identification of mast cell progenitors in adult mice | PNAS
... an orphan receptor in the IL-1 receptor family that is expressed on T helper type 2 cells and mast cells (18-20); CD9, a marker ... mast cells are known primarily as critical effector cells of asthma and other IgE-associated allergic disorders (2-4). However ... including histamine, leukotrienes, prostaglandins, serine proteases, and various cytokines, chemokines, and growth factors (2-4 ... MCPs reconstitute mast cell compartments in mast cell-deficient KitW-sh/KitW-sh mice. Lethally irradiated KitW-sh/KitW-sh mice ...
A Minor Catalytic Activity of Src Family Kinases Is Sufficient for Maximal Activation of Mast Cells via the High-Affinity IgE...
... of the total Lyn and/or SFK capacity of mast cells available to the FcεRI receptor is sufficient for a maximal mast cell ... Genetic variation influences FcεRI-induced mast cell activation and allergic responses. J. Immunol. 179: 740-743. ... Reduced Lyn kinase activity does not impair cytokine production or histamine release in WeeB mast cells after low-intensity ... Cells with metachromatically stained granules were counted as mast cells. D, The percentage of degranulated mast cells was ...
Hay Fever Guide: What is Hayfever?
Hay fever or seasonal allergic rhinitis is an allergic reaction to pollen and other airborne allergens such as fungal spores. ... Mast cells have special receptors to which IgE can bind. When two of these mast cell bound antibodies are together the allergen ... but there is a sensitivity level above which we will suffer an allergic reaction, triggering the release of histamines. Many ... When enough of these are so linked, the mast cells will then release histamines. The body needs histamines - in the brain they ...
PPT - Immune Globulin: The Miracle Product PowerPoint presentation | free to view - id: 37234-NmRiZ
Possible involvement in cell differentiation. 31. IgE*Least common serum isotype *Most IgE bound to IgE Fc receptor on mast ... cells *Antigen binding to IgE releases inflammatory substances *Histamine *Pathogenesis of hay fever, allergic asthma ... Antigen-presenting cell (B Cell). B. Adapted from Israels LG, Israels ED. Mechanisms in Hematology. 1996. 20. Adaptive Humoral ... Secretion of B cell growth factors by activated CD4 cells (IL-4, -5, -6) ...
JCI - Newly identified T cell subsets in mechanistic studies of food immunotherapy
... binding of allergen-specific IgE antibodies to FcεRI receptors on mast cells or basophils that primes the cells for allergic ... and release allergic mediators such as histamine, leukotrienes, and prostaglandins into the surrounding tissue. Symptoms of ... Other cells such as Tfh cells, γδ T cells, and ILC2s are also thought to play a role in allergic reactions. Key cytokines ... Mucosal mast cells and ILC2s also produce Th2-type cytokines: ILC2s produce IL-5 and IL-13, and mucosal mast cells produce Th9 ...
Cutaneous Basophil Hypersensitivity | SpringerLink
Receptor modulation of histamine release in isolated purified rat mast cells, Monogr. Allergy 18: 190-192.Google Scholar ... Kaliner, M. A., 1980, Is a mast cell a mast cell a mast cell ?, J. Allergy Clin. Immunol 66: 1-4.PubMedGoogle Scholar ... Dvorak, A. M., Mihm, M. C., Jr., and Dvorak, H. F., 1976a, Degranulation of basophilic leukocytes in allergic contact ... Development of rat mast cells in vitro. I. Differentiation of mast cells from thymus cells, J. Immunol. 116: 747-754.PubMed ...
Mast Cell Activation Syndrome Madness.... - The Patient Celiac - Celiac.com
At this time last year I had never heard of mast cell activation syndrome (MCAS) and the first time that I heard the name I ... but are best known for their participation in the allergic response. When mast cells degranulate, or burst open, histamine and ... they prevent symptoms by blocking histamine receptors. ... In mast cell activation syndrome (also known as mast cell ... Systemic mastocytosis (SM) is a well-known, very serious mast cell disease in which there are too many mast cells in the body ...
Tox and Hound - Twisted Interactions
... activates mast cells. The mast cells release histamine into the bloodstream, binding receptors in vasculature, skin, and ... In addition to mediating allergic response, histamine is involved in wakefulness. Histamine receptors exist in throughout the ... In this way, software and cell models, supplemented with ECGs performed on just a small number of trial participants, may be ... The H1 histamine receptor, which mediates allergic response, is coupled to a G protein that triggers a cascade of responses in ...
Inflammatory mediatorsInfiltrationAsthmaReactionIntracellularMacrophagesKetotifenSymptomsProteasesEffects of histamineAllergensTreatment of allergicAnaphylaxisEffector cellsInflammationGranulesDiseasesMiceAntagonistsChemical mediatorsAntigensAllergyProtein-coupled receptorsHypersensitivityAntihistamineBindsBone marrowDegranulateProinflammatoryMoleculesSurface receptorsBoundTriggersInhibiting histamine releaseImmune cellsImmunoglobulinBindAnaphylacticPathogenesisAntihistamines and mast cell stabilisersDisabling the allergic responseTissueSecreteResponseUrticariaVitroProteinsHistidineAllergen-specific
- 1. Antagonizing effect on inflammatory mediators: Clinical studies have already demonstrated that ketotifen fumarate can effectively inhibit the histamine-induced bronchospasm with its intensity being comparable to Azelastine, suggesting that ketotifen fumarate has strong histamine antagonistic effect. (chemicalbook.com)
- 2. The membrane protective effect of mast cells/basophils: the related pharmacological studies of ketotifen fumarate have confirmed that it can inhibit mast cell /basophil cells to release inflammatory mediators such as histamine, leukotrienes and platelet activating factor, suggesting that it has a strong membrane protective effects on mast cells/basophils membrane. (chemicalbook.com)
- I also found exercise would greatly exacerbate my symptoms, and I remember reading somewhere that it can trigger histamine release. (healingwell.com)
- These agents decrease or prevent allergic symptoms caused by histamine receptors from mast cells. (medscape.com)
- http://www.afdo.org/afdo/upload/ROP.pdf ?Symptoms of increased histamine release include impurities (characteristically produced by bathing or showering), heartburn, acid eructation, peptic ulcer, small bowel hypermotility, flushing and angioneurotic edema. (google.com)
- The body needs histamines - in the brain they keep us alert, attentive and awake - but when there are too many in the body, it is these histamines which are mainly responsible for causing the unpleasant hay fever symptoms. (haymax.biz)
- Symptoms are caused by having too much histamine in one's system and can affect almost any part of the body (see comprehensive list below). (celiac.com)
- Most of us are familiar with the antihistamine drugs that are used to treat allergic symptoms, such as Claritin, Allergra, and Zrytec. (celiac.com)
- Although these medications do not prevent mast cells from releasing histamine, they prevent symptoms by blocking histamine receptors. (celiac.com)
- Some patients will experience only one or two symptoms from having too much histamine floating around, and other patients will experience many, many symptoms. (celiac.com)
- A 1982 randomized-controlled trial of nearly 400 patients that compared terfenadine vs 1st-generation antihistamine chlorpheniramine vs placebo found the active drugs had comparable effects on allergic symptoms (60% in both groups had moderate to complete relief). (emcrit.org)
- These mediators are responsible for the symptoms in allergic conditions such as allergic asthma. (frontiersin.org)
- These cells release chemical messengers in the body that cause the symptoms of an allergic reaction. (emedicinehealth.com)
- By occupying the histamine receptor sites, they prevent histamine from causing the characteristic allergic symptoms. (emedicinehealth.com)
- In this way, the symptoms of an allergic reaction are produced. (dictionary.com)
- Those with MCAS have overactive mast cells that release too many chemicals into the body at inappropriate times, resulting in a variety of symptoms that, up until recently, have been difficult for physicians to identify. (drlam.com)
- Because of its connection to norepinephrine, the adrenals, and how the body responds to the stress of standing, POTS is strongly associated with Mast cell activation and adrenal disorders in both its action and symptoms. (drlam.com)
- Anti-allergy drugs can treat allergic symptoms by interfering at one of several points in this process. (foley.com)
- By contrast, drugs known as mast cell stabilizers prevent mast cells from releasing mediators, and thus counteract the effects of histamine and other mediators that cause allergic symptoms. (foley.com)
- The compound's primary mechanisms of action are believed to make it an effective treatment against the signs and symptoms of allergic conjunctivitis. (bio-medicine.org)
- A Michigan State University researcher is providing new insight into how certain types of stress interact with immune cells and can regulate how these cells respond to allergens, ultimately causing physical symptoms and disease. (medicalxpress.com)
- Most people know about histamine because of antihistamines , drugs commonly used to manage allergy symptoms. (selfhacked.com)
- The symptoms of the allergic reaction may range from mild to severe. (wikipedia.org)
- A severe case of an allergic reaction, caused by symptoms affecting the respiratory tract and blood circulation, is called anaphylaxis . (wikipedia.org)
- Many of the symptoms associated with mastocytoma are due to chemicals contained within mast cell granules, such as histamine. (oncolink.org)
- In the cat, histamine can cause allergic type symptoms, such as low blood pressure and difficulty breathing. (oncolink.org)
- Topical antihistamines and mast cell stabilisers, alone or in combination, are safe and effective for reducing symptoms of seasonal and perennial allergic conjunctivitis. (cochrane.org)
- It seems that all reported topical antihistamines and mast cell stabilisers reduce symptoms and signs of seasonal allergic conjunctivitis when compared with placebo in the short term. (cochrane.org)
- Seasonal/perennial allergic conjunctivitis is the most common allergic conjunctivitis, usually with acute manifestations when a person is exposed to allergens and with typical signs and symptoms including itching, redness, and tearing. (cochrane.org)
- The clinical signs and symptoms of allergic conjunctivitis are mediated by the release of histamine by mast cells. (cochrane.org)
- Corticosteroid creams can be rubbed into the affected area to lessen the symptoms of the allergic reaction, but this will not shorten the duration of the rash. (stlouischildrens.org)
- A person who has or had MS claims that taking histamine and caffeine improves symptoms of fatigue and prevents progression of the disease. (rutgers.edu)
- Mast cells are best known as the culprits that produce the histamine and other molecules responsible for allergic symptoms, ranging from the itch of eczema to the mucous explosions of hay fever to the throat constriction of asthma or food-triggered anaphylaxis. (scienceblog.com)
- In the study, Robinson's group used electron microscopy to show that mast cells in injured joints of humans who didn't yet have arthritic symptoms weren't releasing their histamine- and tryptase-laden granules, whereas mast cells residing in the joints of humans with arthritic symptoms were. (scienceblog.com)
- Several types of genetically altered lab mice whose mast cells were deficient or absent were highly resistant to the development of osteoarthritic features including joint inflammation, osteophyte development and joint breakdown after undergoing an experimental procedure to induce these symptoms, the researchers found. (scienceblog.com)
- Mast cells and basophils release preformed chemical mediators (i.e. histamine, tryptase, carboxypeptidase A, and proteoglycans) as well as newly generated mediators (i.e. leukotrienes, prostaglandins, platelet-activating factor, and various cytokines) that induce various symptoms of anaphylaxis. (renalandurologynews.com)
- FcεRI) and can be activated by IgE and specific antigen to release a diverse array of mediators, including histamine, leukotrienes, prostaglandins, serine proteases, and various cytokines, chemokines, and growth factors ( 2 - 4 ). (pnas.org)
- Cross-linking of cell surface IgE bound to FcεRI by Ag leads to the rapid release of inflammatory mediators, including histamine, proteases, arachidonic acid metabolites, and various cytokines ( 2 ). (jimmunol.org)
- These mediators can either be preformed (e.g., histamine, proteases, cytotoxic proteins) and released within seconds to minutes after activation, or de novo synthesized (e.g., arachidonic acid metabolites, chemokines, cytokines) and released minutes to hours to days after activation. (worldallergy.org)
- Mast cells rapidly degranulate upon crosslinking of specific IgE by corresponding allergens and release preformed histamine, proteases (chymase, tryptase) and cytokines (TNF-alpha), followed by the rapid synthesis and release of prostaglandins and leukotrienes. (worldallergy.org)
- Mast cells are tissue cells that exert their biological effects by releasing preformed and de novo synthesised mediators such as histamine, proteases, leukotrienes, prostaglandins, and cytokines on cell activation by IgE receptor crosslinking and other less defined cellular signals. (bmj.com)
- These cells trigger an inflammatory cascade by secreting numerous preformed pro-inflammatory chemical mediators such as histamine, proteases and cytokines into the blood. (bmj.com)
Effects of histamine5
- Mast cells are major producers of histamine, yet effects of histamine on mast cells are currently unclear. (aspetjournals.org)
- The diverse biological effects of histamine are mediated through different histamine receptors, which are all G protein-coupled receptors. (aspetjournals.org)
- However, not all effects of histamine can be attributed to these three histamine receptors. (aspetjournals.org)
- Histamine antagonists (also called antihistamines) inhibit the action of histamine by blocking histamine H1 receptors, antagonising the vasoconstrictor, and to a lesser extent, the vasodilator effects of histamine. (cochrane.org)
- Currently, most allergy treatments focus on either stopping the effects of histamine and other mediators or on dampening the body's overall immune response by use of steroids. (eurekalert.org)
- When IgE antibodies bind with allergens, they cause the mast cell to release histamine and other chemicals, which spill out onto neighboring cells. (thefreedictionary.com)
- Overall, mast cells are the main players in the early phase of the allergic reaction, due to their resident localization at sites where they are most likely to encounter environmental or food allergens (e.g., submucosa of the respiratory or digestive tract). (worldallergy.org)
- One chemical substance, histamine, is known to help the body get rid of invading allergens such as pollen, dust mites or the protein of a particular food like a peanut or shellfish. (medicalxpress.com)
- In response to allergens - such as pollen, dust mites, or peanuts - mast cells release a chemical substance called histamine, which works to rid the body of these allergens. (medicalnewstoday.com)
- Left: mast cells are activated by allergens reacting with IgE bound to IgE receptors on the mast cell surface to trigger the release of histamine and other inflammatory mediators that. (eurekalert.org)
- A detailed understanding of the immunological mechanisms that underlie the development of allergic disease, as well as the processes that drive immune tolerance to allergens, will be instrumental in designing therapeutic strategies to treat and prevent allergic disease. (jci.org)
- In-depth analysis of the cells and tissues of patients treated with such targeted interventions provides a wealth of information on the mechanisms that drive allergies and tolerance to allergens. (jci.org)
- Allergens and pathogens that have passed the skin or mucosal epithelium are phagocytosed by antigen-presenting cells (APCs). (jci.org)
Treatment of allergic8
- Presently, most pharmacological agents for the treatment of allergic disease target receptors for inflammatory mediators. (aspetjournals.org)
- The district court had construed that language in conjunction with the "stabilizing conjunctival mast cells" language, and interpreted the claims as reciting "concentrations of olopatadine that stabilize conjunctival mast cells 'to an extent clinically relevant in the treatment of allergic eye disease. (foley.com)
- IRVINE, Calif., May 08, 2007 /PRNewswire-FirstCall/ -- ISTA Pharmaceuticals, Inc., today announced results from the preliminary analysis of its U.S. Phase II/III clinical study of bepotastine for the treatment of allergic conjunctivitis. (bio-medicine.org)
- ISTA plans to complete the Phase II/III study analysis and then discuss the results with the Food and Drug Administration to determine the remaining clinical studies required to confirm ocular safety and efficacy for the submission of an NDA for bepotastine for the treatment of allergic conjunctivitis. (bio-medicine.org)
- In 2006, ISTA licensed from Senju the exclusive North American rights to an eye drop formulation of bepotastine for the treatment of allergic conjunctivitis. (bio-medicine.org)
- While it may be tempting for clinicians involved with the treatment of allergic individuals to only consider the negative roles of these three cell types, it is important to consider that causing allergic diseases is not their physiological function, and that they play important protective roles. (worldallergy.org)
- Given the success of exon skipping in clinical trials to treat genetic diseases such as Duchenne muscular dystrophy, we propose that exon skipping of FcεRIβ is a potential approach for mast cell-specific treatment of allergic diseases. (eurekalert.org)
- The present invention also provides pharmaceutical compositions, for the treatment of allergic diseases and for the treatment of hyperplasias and malignancies, comprising as an active ingredient the above mentioned chimeric protein and a conventional adjuvant product. (google.com)
- Physical factors such as exercise (known as exercise-induced anaphylaxis) or temperature (either hot or cold) may also act as triggers through their direct effects on mast cells. (wikipedia.org)
- 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 and defense against pathogens . (wikidoc.org)
- Through several different intricate experiments these peptides were found to suppress passive cutaneous anaphylaxis and mast cell-dependent airway inflammation and substantially reduce allergic airway inflammation. (bmj.com)
- Accordingly, mast cells are known primarily as critical effector cells of asthma and other IgE-associated allergic disorders ( 2 - 4 ). (pnas.org)
- Mast cells are effector cells that mediate the allergic response through Ag stimulation of IgE bound to FcεRI. (jimmunol.org)
- IgE-mediated food-allergic disease differs from non-IgE-mediated disease because the pathophysiology results from activation of the immune system, causing a T helper 2 response which results in IgE binding to Fc ε receptors on effector cells like mast cells and basophils. (readbyqxmd.com)
- Secretagogue-induced histamine release, inflammation and airway contraction are abolished in Mrgprb2-null mutant mice. (nih.gov)
- Further research on the complex cross talk between receptors during inflammation is also helping to elucidate the mediators and signalling pathways activated by acupuncture. (hindawi.com)
- The histamine then binds to histamine receptors in other cells of the body, which initiate the response known as inflammation as well as other responses. (dictionary.com)
- Endogenous factors, including reactive oxygen species, and damage-associated molecular patterns (DAMPs) recognized by toll-like receptors (TLRs), can also result in airway inflammation. (frontiersin.org)
- These have receptors that release histamine and other substances when they perceive a 'threat' (like medication), thus causing inflammation. (shinyshiny.tv)
- The in vitro study elucidated inhibitory effects of kaempferol, a flavonoid found in apples and many berries, on inflammation in human airway epithelial BEAS-2B cells. (hindawi.com)
- Proinflammatory IL-8 is secreted by macrophages and lung epithelial cell into lung fluid and recruits neutrophils and eosinophils to the sites of inflammation [ 7 ]. (hindawi.com)
- Exposure to lipopolysaccharide (LPS) increases the severity of asthma, which activates Toll-like receptor (TLR) signaling in the regulation of Th2-driven lung inflammation [ 9 ]. (hindawi.com)
- If this process shifts out of balance, too much histamine triggers inflammation and allergies. (selfhacked.com)
- Recent investigations in a murine model have demonstrated that mast cells can have a critical role in the generation of inflammation within the joint. (biomedcentral.com)
- In an attempt to fight off the invaders, mast cells release histamine, which when binding to histamine receptors on skin cells, result in inflammation. (stlouischildrens.org)
- By eliminating the expression of the IgE receptor on the surface of mast cells, we have identified an innovative and targeted approach with the potential to treat allergic inflammation in millions of patients worldwide. (eurekalert.org)
- The data suggest that smoke exposure enhances antigen-induced mast cell activation via TGF-β/Smad signaling pathways in mouse allergic asthma, and that it exacerbates airway inflammation and remodeling. (biomedcentral.com)
- Effects of smoke on allergic airway inflammation in mice have reported both exacerbation [ 4 - 8 ] and attenuation [ 9 - 11 ], although these studies could not be directly compared due to differences in the various factors used, such as mouse strain, the routes and manners of allergen sensitization and smoke exposure. (biomedcentral.com)
- Mast cells are specialized cells derived from stem cells in the bone marrow and play an important role in helping an animal respond to inflammation and allergies. (animalmedcenter.com)
- Mast cell activation results in the immediate release of proinflammatory mediators prestored in cytoplasmic granules, as well as initiation of lipid mediator production and cytokine synthesis by these resident tissue leukocytes. (aspetjournals.org)
- Adenosine 5′-triphosphate (ATP, compound 3 in Figure 1 ) is abundant in mast cells, stored in granules and secreted upon activation. (frontiersin.org)
- Each mast cell has what is known as secretory granules, which contain mediators. (drlam.com)
- Specific granules, which define final cell types, are first produced at the myelocyte stage. (merckvetmanual.com)
- Cell types are recognized by characteristic granule staining affinity, eg, basophilic granules for basophils, eosinophilic granules for eosinophils, and neutral or nonstaining granules for neutrophils. (merckvetmanual.com)
- Within seconds to minutes of IgE crosslinking, granules in the cytoplasm of the mast cell fuse with each other and with the cell surface membrane, ejecting their contents into the extracellular milieu. (biomedcentral.com)
- Mast cells were first described by Paul Ehrlich in his 1878 doctoral thesis on the basis of their unique staining characteristics and large granules. (wikidoc.org)
- These granules also led him to the mistaken belief that they existed to nourish the surrounding tissue, and he named them "mastzellen," a german term, meaning "feeding-cells. (wikidoc.org)
- When activated, a mast cell rapidly releases its characteristic granules and various hormonal mediators into the interstitium. (wikidoc.org)
- But when they become activated, they secrete granules containing histamine, tryptase and other inflammatory substances. (scienceblog.com)
- In all, the scientists were able to get the same osteoarthritis-protective results using a number of genetic tricks, as well as three small-molecule compounds that each blocked a separate stage of the cascade via which IgE trips off mast-cell activation and secretion of granules containing collagen-chewing tryptase. (scienceblog.com)
- Allergen-induced mast cell activation is central to the pathogenesis of asthma and other allergic diseases. (aspetjournals.org)
- 1. A method for treating allergic eye diseases in humans comprising stabilizing conjuctival mast cells by topically administering to the eye a composition comprising a therapeutically effective amount of 11-(3-dimethylaminopropylidene)-6,11-dihydrodibenz(b,e)oxepin-2-acetic acid or a pharmaceutically acceptable salt thereof. (foley.com)
- Therefore, therapies that reduce eosinophil numbers are usually effective in allergic diseases. (worldallergy.org)
- Mast cells become highly activated in response to stressful situations the body may be experiencing," said Adam Moeser, an associate professor and endowed chair who specializes in stress-induced diseases. (medicalxpress.com)
- When this happens, CRF1 tells these cells to release chemical substances that can lead to inflammatory and allergic diseases such as irritable bowel syndrome, asthma, life-threatening food allergies and autoimmune disorders such as lupus. (medicalxpress.com)
- This work is a critical step forward in decoding how stress makes us sick and provides a new target pathway in the mast cell for therapies to improve the quality of life of people suffering from common stress -related diseases. (medicalxpress.com)
- This causes immune cells to release chemical substances that can trigger a host of diseases, including asthma , lupus , and irritable bowel syndrome (IBS). (medicalnewstoday.com)
- Mast cells are present in limited numbers in normal human synovium, but in rheumatoid arthritis and other inflammatory joint diseases this population can expand to constitute 5% or more of all synovial cells. (biomedcentral.com)
- Biomedical research has long sought to exploit their pleiotropic properties as a basis for cell therapy for a variety of diseases and to facilitate hematopoietic stem cell establishment and stromal reconstruction in bone marrow transplantation. (wjgnet.com)
- Early experimental and preclinical studies focused on their stem cell renewal, differentiation, and regenerative properties for potential use in degenerative diseases of mesenchymal origin. (wjgnet.com)
- Over half of the US population possesses sensitivity to at least one allergen, and allergic diseases rank 5th in the list of leading chronic diseases. (jyi.org)
- Asthma and allergic diseases affect up to 20 percent of people in developed countries, and their prevalence is increasing," says Cruse. (eurekalert.org)
- Abstract: Allergic diseases are driven by activation of mast cells and release of mediators in response to IgE-directed antigens. (eurekalert.org)
- Development of allergic diseases starts with a sensitization phase ( Figure 1 ). (jci.org)
- The alarming increase in the prevalence of allergic diseases over the past decade has led to a clear need for more effective treatment. (google.com)
- What we found is that the CRF2 receptor can act as an inhibitor, or a control point, in mast cells, which prevents them from becoming overactivated," said Adam Moeser, lead author and an associate professor specializing in stress-induced diseases. (innovationtoronto.com)
- This chemotactic response is mediated by the H 4 receptor, because chemotaxis toward histamine was absent in mast cells derived from H 4 receptor-deficient mice but was detected in H 3 receptor-deficient mast cells. (aspetjournals.org)
- In vitro studies using cultured human and mouse mast cells, and studies of mice lacking A 2B receptors, suggest that adenosine receptors, specifically the G s -coupled A 2A and A 2B receptors, might provide such a target. (aspetjournals.org)
- In the current study the Dong lab has identified a single cell surface receptor (called MRGPRX2 in humans and Mrgprb2 in mice) is the culprit of these side-effects. (jhu.edu)
- Strikingly, mice without this receptor exhibited no allergic symptom as seen in normal mice. (jhu.edu)
- The gene encoding stem cell factor (SCF) is found on the Sl locus in mice and on chromosome 12q22-12q24 in humans. (wikidoc.org)
- Mice that do not express the receptor for SCF (c-KIT) also die from anemia. (wikidoc.org)
- In adult mice, the injection of the ACK2 anti-KIT antibody , which binds to the c-Kit receptor and inactivates it, leads to severe problems in hematopoiesis. (wikidoc.org)
- We identified a cell population in adult mouse bone marrow, characterized as Lin - c-Kit + Sca-1 - -Ly6c - FcεRIα - CD27 - β7 + T1/ST2 + , that gives rise only to mast cells in culture and that can reconstitute the mast cell compartment when transferred into c- kit mutant mast cell-deficient mice. (pnas.org)
- C57BL/Ka-Thy1.1 (CD45.2) mice (4-8 weeks old) were used for the isolation of MCPs, other myeloid progenitors, hematopoietic stem cells (HSCs), and MPPs. (pnas.org)
- The congenic C57BL/Ka-Thy1.1-Ly5.2 (CD45.1) mice (4-8 weeks old) were used for the isolation of CD45.1 + MCPs for transferring into genetically mast cell-deficient C57BL/6- Kit W-sh /Kit W-sh (CD45.2) mice (6-8 weeks old). (pnas.org)
- McNeil found a receptor in mice that, like the human receptor, is found only in mast cells. (newswise.com)
- During the study, Moeser compared the histamine responses of mice to two types of stress conditions - psychological and allergic - where the immune system becomes overworked. (medicalxpress.com)
- One group of mice was considered "normal" with CRF1 receptors on their mast cells and the other group had cells that lacked CRF1. (medicalxpress.com)
- While the 'normal' mice exposed to stress exhibited high histamine levels and disease, the mice without CRF1 had low histamine levels, less disease and were protected against both types of stress," Moeser said. (medicalxpress.com)
- The CRF1-deficient mice exposed to allergic stress had a 54 percent reduction in disease, while those mice who experienced psychological stress had a 63 percent decrease. (medicalxpress.com)
- They then disabled the gene for this receptor in mice and found that it halted the pseudo-allergic response, regardless of the substance tested. (shinyshiny.tv)
- This study further explored the blockade of Tyk-STAT signaling by kaempferol in both LPS-stimulated BEAS-2B cells and OVA-challenged mice. (hindawi.com)
- For their study, the researchers looked at two groups of mice: one that had normal CRF1 receptors on their mast cells, and one that was lacking in CRF1 receptors. (medicalnewstoday.com)
- In the study, both groups of mice were exposed to psychological stress and allergic stress, wherein the immune system becomes overactive. (medicalnewstoday.com)
- The researchers found that the mice with normal CRF1 receptors on their mast cells experienced an increase in histamine levels in response to both stress conditions, and this led to disease. (medicalnewstoday.com)
- Mice that lacked CRF1 receptors saw a 54 percent decrease in disease in response to allergic stress, and a 63 percent decline in disease in response to psychological stress. (medicalnewstoday.com)
- Correspondingly, mice deficient in mast cells have been found to exhibit striking susceptibility to death from certain types of bacterial infection. (biomedcentral.com)
- In a study published online May 14 in eLife , the scientists demonstrated for the first time that banishing mast cells - or blocking signals from the most common stimulus activating them in real life, or disabling a cartilage-degrading enzyme they release when activated - all protected mice from developing osteoarthritis induced by an experimental procedure. (scienceblog.com)
- Their results in vivo showed a marked reduction in the allergic dermatitis response in the mice. (eurekalert.org)
- Moeser was able to duplicate the same result by isolating mice, pig and human mast cells. (innovationtoronto.com)
- FcεRI is expressed on mast cells , basophils , and the antigen-presenting dendritic cells in both mice and humans. (wikipedia.org)
- Mast cell chemotaxis toward histamine could be blocked by the dual H 3 /H 4 receptor antagonist thioperamide, but not by H 1 or H 2 receptor antagonists. (aspetjournals.org)
- Almost a century of extensive pharmacological research using specific histamine receptor agonists and antagonists has identified three histamine receptors (H 1 , H 2 , and H 3 receptor). (aspetjournals.org)
- It was shown that specific H 1 and H 2 receptor antagonists and agonists do not bind to the H 4 receptor. (aspetjournals.org)
- and this also explains the benefits of using histamine receptor antagonists. (worldallergy.org)
- complement-dependent hypersensitivity to foreign cells or to alterations of cell-surface antigens that is mediated by immunoglobulin G (IgG) or IgM. (thefreedictionary.com)
- These antigens stimulate the bodies' mast cells, which then break or degranulate, releasing mediators that include histamines. (haymax.biz)
- A molecular structure or site on the surface or interior of a cell that binds with substances such as hormones, antigens, drugs, or neurotransmitters. (dictionary.com)
- B- Lymphocytes in the body have cell surface receptors for foreign bodies or antigens. (mybiosource.com)
- These structures are strategically located to allow the nodule cells to intercept and react with foreign antigens and then travel to regional lymph nodes, where they undergo proliferation and differentiation. (freeonlineresearchpapers.com)
- G. Marone and L.M. Lichtenstein , Adenosine-Adenosine Deaminase Modulation of Histamine Release , J. Allergy clin Immunol. (springer.com)
- As our appreciation of different T cell subsets and their plasticity increases, the initial simplistic view that restoring Th1/Th2 balance by decreasing Th2 or increasing Th1 responses can ameliorate food allergy is being enhanced by a more complex model involving other T cell subsets, particularly Tregs. (jci.org)
- In this Review, we focus on the current understanding of T cell functions in food allergy, tolerance, and immunotherapy. (jci.org)
- Histamine is a chemical released by specialized allergy cells called activated mast cells during the allergic response. (emedicinehealth.com)
- To compare and test the reliability and consistency of 2 different food allergy testing methods: cell size allergy testing versus IgG ELISA food allergy testing within the same donor. (naturalmedicinejournal.com)
- This finding highlights the results of more than 20 years of research indicating that mast cells are frequent participants in non-allergic immune responses as well as in allergy. (biomedcentral.com)
- The role of mast cells in the development of allergy. (wikidoc.org)
- The activation of these cells causes release of histamine and other preformed mediators, and rapid symptom onset, in contrast with non-IgE-mediated food allergy which is more delayed in onset. (readbyqxmd.com)
- Askenase, P. W., 1976, Cutaneous basophil hypersensitivity uncovered in the cell transfer of classical tuberculin hypersensitivity, J. Immunol. (springer.com)
- In contrast to an IgE allergic response which is faster and more severe, food hypersensitivity is a delayed type cell-mediated response. (naturalmedicinejournal.com)
- First-generation antihistamine that binds to H1 receptors in the CNS and the body. (medscape.com)
- An antihistamine works by blocking the action of the histamine, which works well for some people and is one of the most popular methods of treating hay fever. (haymax.biz)
- Antihistamine drugs work by preventing the binding of histamine to histamine receptors. (dictionary.com)
- The '805 patent acknowledges that olopatadine was known to be an effective antihistamine, and characterizes the invention as relating to the discovery that olopatadine has mast cell stabilizing activity. (foley.com)
- Kamei also reported that "although olopatadine is a good antihistamine, it is not an effective mast cell stabilizer. (foley.com)
- This typically includes antihistamine-type drugs that work on the two types of histamine receptors, H1 and H2. (oncolink.org)
- Cyproheptadine is an H1 antihistamine drug that is most commonly used as an appetite stimulant in cats, but can also be used to treat mast cell tumor. (oncolink.org)
- Stem cell factor (also known as SCF , KIT-ligand , KL , or steel factor ) is a cytokine that binds to the c-KIT receptor ( CD117 ). (wikidoc.org)
- The allergen binds to the Fab part of the IgE molecules on the mast cell surface. (wikidoc.org)
- Allergen-specific IgE binds to FcεRI on mast cells and basophils. (jci.org)
- IgE binds to high-affinity receptor (FcεRI) for its constant region, found almost exclusively on the surface of these cells. (google.com)
- SCF plays a role in the regulation of HSCs in the stem cell niche in the bone marrow. (wikidoc.org)
- In the bone marrow, HSCs and hematopoietic progenitor cells are adjacent to stromal cells, such as fibroblasts and osteoblasts (Figure 2). (wikidoc.org)
- It causes a significant decrease in the number HSC and other hematopoietic progenitor cells in the bone marrow. (wikidoc.org)
- High-intensity stimulation of lyn −/− bone marrow-derived mast cells with highly multivalent Ag resulted in enhanced cytokine production as previously reported, and WeeB cells displayed an intermediate phenotype. (jimmunol.org)
- Despite its predominance, Lyn-deficient bone marrow-derived mast cells (BMMCs) still respond to FcεRI engagement, with hyperresponsiveness observed under some conditions and hyporesponsiveness observed in others ( 6 , 8 - 11 ). (jimmunol.org)
- During initiation of an inflammatory lesion, local mononuclear cell release of specific stimulating factors rapidly stimulates bone marrow to release neutrophil reserve and accelerate granulopoiesis. (merckvetmanual.com)
- However, current evidence suggests that they are generated by different precursor cells in the bone marrow. (wikidoc.org)
- Nevertheless, both mast cells and basophils are thought to originate from bone marrow precursors expressing the CD34 molecule. (wikidoc.org)
- The basophil leaves the bone marrow already mature while the mast cell circulates in an immature form, only maturing once in a tissue site. (wikidoc.org)
- The mast cell tumor may also be diffusely spread to other sites, such as the liver, lymph nodes, bone marrow, and skin. (oncolink.org)
- For cats with mast cell tumor of the spleen that are stable enough to tolerate surgery, removal of the spleen can result in significant improvement, even in cats that have involvement of the bone marrow. (oncolink.org)
- The chimeric protein, produced in E. coli , specifically and efficiently kills mouse mast cell lines expressing the FcεRI receptor, as well as primary mast cells derived from bone marrow. (google.com)
- When these cells encounter triggering foods, they degranulate, which may include the release of histamine. (naturalmedicinejournal.com)
- Mast cells can be stimulated to degranulate by direct injury (e.g physical or chemical), cross-linking of IgE receptors, or by activated complement proteins. (wikidoc.org)
- Targeting pathways that limit antigen-induced mast cell activation may have greater therapeutic efficacy by inhibiting the synthesis and release of many proinflammatory mediators produced in the mast cell. (aspetjournals.org)
- Once the receptor is triggered, it causes mast cells to release histamine and many other proinflammatory reagents. (jhu.edu)
- Crosslinking of surface-bound IgE results in the immediate release of granule contents, including histamine, and the more gradual elaboration of other proinflammatory mediators. (biomedcentral.com)
- Antigen binding to two adjacent IgE molecules causes perturbation of the cell membrane leading to the release of vasoactive substances. (thefreedictionary.com)
- Lyn phosphorylates the ITAMs in the cytoplasmic domains of the β- and γ-chains, which leads to the recruitment of additional Lyn to the β-chain, the tyrosine kinase Syk to the γ-chains, and other signaling and scaffolding molecules to the aggregated receptor complex ( 3 - 5 ). (jimmunol.org)
- These are biologically active molecules, that, once a mast cell is triggered, are secreted and cause an allergic or inflammatory response . (drlam.com)
- 1-4 Moreover, TNF-α induces endothelial adhesion molecules and thus may initiate the recruitment of circulatory inflammatory cells into the tissue. (bmj.com)
- This receptor is of such high affinity that binding of IgE molecules is essentially irreversible. (wikidoc.org)
- A research team led by Dr. Chris Kepley from Virginia Commonwealth University Health System (VCU) found that soccerball-shaped, 60 carbon-caged nanoparticles known as fullerenes, or buckyballs, suppress the allergic response by inhibiting the release of histamines and other inflammatory molecules. (jyi.org)
- Mast Cells and Peripheral Blood Basophils are the storage facilities for inflammatory molecules and defenders of the body's immune system. (jyi.org)
- The IgE receptor acts as a key that frees inflammatory molecules. (jyi.org)
- If effectively generated, the altered fullerene will be able to specifically target Mast Cells and Peripheral Blood Basophils and provide more knowledge on the effects of IgE and the stem cell factor have on the release of the inflammatory molecules. (jyi.org)
- The frequent alternative splicing (as a likely mechanism generating activator receptors), the presence of KIR4DL and KIR2DL1 (D0+D1) molecules and other data reported here suggest that the KIR family in Aotus has had a rapid evolution, independent from its Catarrhini counterparts. (jove.com)
- But mast cells also produce a degradative protein, tryptase, that can rip up collagens and other molecules that form the cartilage in joints. (scienceblog.com)
- These IgE molecules are fixed to high affinity IgE receptors (FceRI) on the surface of mast cells, basophils and various antigen-presenting cells, e.g., macrophages, dendritic cells, Langerhans cells. (renalandurologynews.com)
- The actions of LTB 4 are mediated by two cell surface receptors, BLT1, which is predominantly expressed in peripheral blood leukocytes, and BLT2, which is expressed ubiquitously ( 21 - 23 ). (jimmunol.org)
- Equipped with a diversity of surface receptors and effector capabilities, mast cells are sentinels of the immune system, detecting and delivering a first response to invading bacteria and other insults. (biomedcentral.com)
- Mast cells express surface receptors for IgG, complement, and specific pathogen-associated molecular patterns. (biomedcentral.com)
- Histamine is the ligand for 2 membrane-bound receptors, the H1 and H2 receptors, which are present on many cell types. (medscape.com)
- In an allergic response, a foreign substance - an allergen - is bound by IgE, which, in turn, activates mast cells. (emcrit.org)
- Mast cells are activated by cross-linking of antigen-specific IgE bound to the high-affinity receptor (FcεRI) on their membranes. (biomedcentral.com)
- At this point, my only known triggers for MCAS are high histamine foods and foods that are histamine-releasing, including fermented foods and foods/drinks that have added sulfites. (celiac.com)
- Please see my previous post "Celiac Disease and Multiple Food Intolerances" from July 2013 for more details on food triggers and high histamine foods. (celiac.com)
- This triggers the release of inflammatory chemicals such as histamine . (wikipedia.org)
- In addition, histamine triggers stomach acid production which can lead to ulcers. (oncolink.org)
- What triggers an allergic response? (optimalhealthnetwork.com)
Inhibiting histamine release1
- This receptor is exclusively found in a type of immune cells called mast cells. (jhu.edu)
- I. Transfer with immune serum or immune cells, Immunology 45: 501-511. (springer.com)
- Mast cells are innate immune cells that play a role in defending the body against bacteria, viruses, and parasites, but are best known for their participation in the allergic response. (celiac.com)
- The federally funded study, published in the Journal of Leukocyte Biology , showed how a stress receptor, known as corticotropin-releasing factor, or CRF1, can send signals to certain immune cells , called mast cells , and control how they defend the body. (medicalxpress.com)
- Researchers at Michigan State University in East Lansing have revealed how a protein known as corticotropin-releasing factor receptor subtype 1 (CRF1) responds to stress by sending signals to specific immune cells. (medicalnewstoday.com)
- As these changes gain momentum, they may shift the balance in immune cells and reduce barrier integrity in the gut. (selfhacked.com)
- However, the full range of MSC-mediated immune-modulation remains incompletely understood, as emerging reports also reveal that MSCs can adopt an immunogenic phenotype, stimulate immune cells, and yield seemingly contradictory results in experimental animal models of inflammatory disease. (wjgnet.com)
- Once an allergen is inhaled it is processed by the immune cells and stimulates a B-cell mediated IgE response. (optimalhealthnetwork.com)
- However, more typical H 3 receptor ligands (such as thioperamide, clobenpropit, imetit, and R -α-methylhistamine) could bind the H 4 receptor with affinities different from that of the H 3 receptor. (aspetjournals.org)
- Mast cells have special receptors to which IgE can bind. (haymax.biz)
- The H1 antihistamines are not structurally related to histamine and they do not bind the active site of the histamine receptor. (emcrit.org)
- A structure or site, found on the surface of a cell or within a cell, that can bind to a hormone, antigen, or other chemical substance and thereby begin a change in the cell. (dictionary.com)
- For example, when a mast cell within the body encounters an allergen, specialized receptors on the mast cell bind to the allergen, resulting in the release of histamine by the mast cell. (dictionary.com)
- However, mast cells can be activated by many mechanisms in addition to IgE and specific antigen, and these cells have also been implicated in the pathogenesis of autoimmune disorders ( 5 ), in the expression of innate immunity to bacterial infection ( 6 , 7 ), and in a wide variety of other biological processes ( 1 - 7 ). (pnas.org)
- However, the role of BLT2 in mast cells in asthmatic pathogenesis has not been elucidated. (jimmunol.org)
- All three cell are involved in the pathogenesis of allergic disease. (worldallergy.org)
- The aim of our studies is to determine miRNA expression in cancer cell lines and in series of clinically well-annotated tumor samples and to examine the role of aberrantly expressed miRNAs for the pathogenesis of cancer. (libpubmedia.co.uk)
Antihistamines and mast cell stabilisers3
- We found insufficient evidence to discern which topical antihistamines and mast cell stabilisers are the most effective. (cochrane.org)
- Direct comparisons of different antihistamines and mast cell stabilisers need to be interpreted with caution. (cochrane.org)
- Overall, topical antihistamines and mast cell stabilisers appear to be safe and well tolerated. (cochrane.org)
Disabling the allergic response1
- Furthermore, histamine causes a contraction of the cells of the vascular endothelium and increases the vascular permeability, thereby allowing higher-molecular substances to escape into the tissue? (google.com)
- This balance may change dramatically when there is either increased tissue demand associated with the development of an inflammatory process or a stem-cell injury that reduces the marrow production rate. (merckvetmanual.com)
- METHODS Mast cells were isolated from surgery tissue specimens of patients undergoing bowel resection because of cancer. (bmj.com)
- Kaempferol allayed the airway tissue levels of eotaxin-1 and eotaxin receptor CCR3 enhanced by OVA challenge. (hindawi.com)
- Beyond the acute phase of the immune response, mast cells may participate in the response of tissue to injury by means of mediators that promote angiogenesis and fibrosis. (biomedcentral.com)
- Mast cells are found principally in mucosae and in connective tissue, generally clustered at epithelial surfaces and around nerves and blood vessels [ 3 ]. (biomedcentral.com)
- The tissue site an immature mast cell chooses to settle in probably determines its precise characteristics. (wikidoc.org)
- Two types of mast cells are recognized, those from connective tissue and a distinct set of mucosal mast cells. (wikidoc.org)
- When evaluating the tissue sample obtained from surgical removal of the mast cell tumor, the diagnosis of mast cell tumor will be confirmed, the mast cell tumor will be staged, and the width of the tissue margins, which are free of tumor will be measured. (animalmedcenter.com)
- Staging and the width of the tissue margins which are free of tumor cells together with the location of the mass, the health of the dog, and the grade of the mast cell tumor will determine whether further treatment with radiation therapy or chemotherapy will be recommended. (animalmedcenter.com)
- A substance that most people tolerate well, but to which others have an allergic response, is called an allergen. (thefreedictionary.com)
- In addition to mediating allergic response, histamine is involved in wakefulness. (emcrit.org)
- Src family kinases (SFK) are critical for initiating and regulating the response of mast cells activated by engagement of the high-affinity IgE receptor, FcεRI. (jimmunol.org)
- Taken together, our results suggest that the BLT2-Nox1-reactive oxygen species cascade is a previously unsuspected mediatory signaling mechanism to Th2 cytokine production in Ag-stimulated BMMCs, thus contributing to allergic response. (jimmunol.org)
- However, neither the source of ROS generated in response to Ag stimulation nor the pathway by which they are generated in Ag-stimulated mast cells is clearly understood. (jimmunol.org)
- He then tested that receptor by putting it into lab-grown cells and found that they did react to medications that provoke mast cell response. (newswise.com)
- Mast cell releasing histamine during an allergic response, computer illustration. (sciencephoto.com)
- Histamine is released from mast cells in response to an allergen, causing a localized inflammatory immune response. (sciencephoto.com)
- Previous research has shown that the activity of mast cells - a type of immune cell - heightens in response to psychological stress, and this, too, can cause illness. (medicalnewstoday.com)
- However, rodents that lacked CRF1 receptors demonstrated low histamine levels in response to stress, and they experienced less disease. (medicalnewstoday.com)
- Early results demonstrated their usage as safe, and there was little host response to these cells. (wjgnet.com)
- With the newly discovered abilities of buckyball against the allergic response pathway, continued research will be devoted to enhancing their anti-inflammatory effects with the attachment of different functional groups. (jyi.org)
- By stopping the activation of the IgE receptor, fullerene stopped the allergic response. (jyi.org)
- In addition to its prevention of allergic response, fullerene can also act as a reactive oxygen sponge thus preventing oxidative stress. (jyi.org)
- Fullerene's role as an antioxidant is directly linked to it involvement in the inhibition of the allergic response. (jyi.org)
- Mast cells and basophils are key players in the IgE-dependent allergic response. (bmj.com)
- The immune response begins when white blood cells engulf and destroy the allergen. (stlouischildrens.org)
- IgE primes the IgE-mediated allergic response by binding to Fc receptors found on the surface of mast cells and basophils . (wikipedia.org)
- Although it is not yet well understood, IgE may play an important role in the immune system's recognition of cancer , in which the stimulation of a strong cytotoxic response against cells displaying only small amounts of early cancer markers would be beneficial. (wikipedia.org)
- In essence, an allergic response is an overcompensation of the immune system against relatively harmless airborne substances. (optimalhealthnetwork.com)
- This calcium dependent process may be the most important trigger, as well as a major key in preventing the cascading allergic response. (optimalhealthnetwork.com)
- The second phase of the response begins at the same time, as the cell begins to synthesize in p i d - d e r i v e d mediators. (optimalhealthnetwork.com)
- Here we report that basic secretagogues activate mouse mast cells in vitro and in vivo through a single receptor, Mrgprb2, the orthologue of the human G-protein-coupled receptor MRGPRX2. (nih.gov)
- SCF also increases the survival of various hematopoietic progenitor cells, such as megakaryocyte progenitors, in vitro. (wikidoc.org)
- Such Thy-1 lo c-Kit hi "promastocytes" lack expression of FcεRI but can generate FcεRI-expressing functional mast cells in vitro and in vivo ( 12 ). (pnas.org)
- Through complex molecular research techniques it was confirmed that HRF together with HRF-reactive IgE triggered mast cell activation in vitro, confirming its pro-inflammatory role. (bmj.com)
- Cruse and Metcalfe tested their therapy on mast cells in vitro - where it eliminated activation of mast cells by allergen - and against allergic dermatitis in vivo, using a mouse model. (eurekalert.org)
- Here, we describe an innovative approach for targeting mast cells in vitro and in vivo using antisense oligonucleotide-mediated exon skipping of the β-subunit of the high affinity IgE receptor (FcεRIβ) to eliminate surface high affinity IgE receptor (FcεRI) expression and function, rendering mast cells unresponsive to IgE-mediated activation. (eurekalert.org)
- Histamine is synthesized from l -histidine by histidine decarboxylation in specific cell types, such as mast cells, basophils, enterochromaffin-like cells, and neurons. (aspetjournals.org)
- Histamine is produced by the enzymatic decarboxylation of histidine. (google.com)
- An enzyme called histidine decarboxylase ( HDC ) makes histamine from the amino acid histidine . (selfhacked.com)
- Certain microbes, including some gut bacteria , also have the HDC enzyme and can produce histamine from histidine. (selfhacked.com)