Biomaterial Database

Characterization of specific receptors for leukotriene D4 on human alveolar macrophages. 1984

F A Opmeer, and H C Hoogsteden

Using 3H-leukotriene D4, a specific receptor assay has been developed for human alveolar macrophages, obtained by broncho-alveolar lavage of patients undergoing fiberoptic bronchoscopy because of suspected bronchial carcinoma. Lavage was performed in a carcinoma-free lobe of the lung and alveolar macrophages were subsequently isolated and incubated for binding studies. 3H-Leukotriene D4 was found to bind specifically with high affinity (Kd = 3.8 nM), in a saturable manner (Bmax = 90 fmol/10(6) cells), reversible and selective. Specific binding was linear with protein concentration and equilibrium binding at 4 degrees C was reached at 50 min. Scatchard and Hill analysis revealed a single class of binding sites with no cooperativity among the sites. Displacement studies with LTD4, the selective SRS-A antagonist FPL 55712 and with leukotriene C4 revealed respective Ki values of 3.4; 16; and 110 nM. The data suggest that human alveolar macrophages may contain a specific receptor type for LTD4, which has a relatively low affinity for LTC4, and are discussed in relation to modulatory processes in the lung, apart from direct actions of LTD4 on smooth muscle receptors. From the data here acquired, it may be apparent that the study of characteristics of receptors specific for a broncho-active substance like LTD4 on human alveolar macrophages, which play an important role in immuno-inflammatory processes seen in many chronic lung diseases, may yield major insights into the pathogenesis and therapy decisions involved in these diseases.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008264	Macrophages	The relatively long-lived phagocytic cell of mammalian tissues that are derived from blood MONOCYTES. Main types are PERITONEAL MACROPHAGES; ALVEOLAR MACROPHAGES; HISTIOCYTES; KUPFFER CELLS of the liver; and OSTEOCLASTS. They may further differentiate within chronic inflammatory lesions to EPITHELIOID CELLS or may fuse to form FOREIGN BODY GIANT CELLS or LANGHANS GIANT CELLS. (from The Dictionary of Cell Biology, Lackie and Dow, 3rd ed.)	Bone Marrow-Derived Macrophages,Monocyte-Derived Macrophages,Macrophage,Macrophages, Monocyte-Derived,Bone Marrow Derived Macrophages,Bone Marrow-Derived Macrophage,Macrophage, Bone Marrow-Derived,Macrophage, Monocyte-Derived,Macrophages, Bone Marrow-Derived,Macrophages, Monocyte Derived,Monocyte Derived Macrophages,Monocyte-Derived Macrophage
D011956	Receptors, Cell Surface	Cell surface proteins that bind signalling molecules external to the cell with high affinity and convert this extracellular event into one or more intracellular signals that alter the behavior of the target cell (From Alberts, Molecular Biology of the Cell, 2nd ed, pp693-5). Cell surface receptors, unlike enzymes, do not chemically alter their ligands.	Cell Surface Receptor,Cell Surface Receptors,Hormone Receptors, Cell Surface,Receptors, Endogenous Substances,Cell Surface Hormone Receptors,Endogenous Substances Receptors,Receptor, Cell Surface,Surface Receptor, Cell
D011982	Receptors, Prostaglandin	Cell surface receptors that bind prostaglandins with high affinity and trigger intracellular changes which influence the behavior of cells. Prostaglandin receptor subtypes have been tentatively named according to their relative affinities for the endogenous prostaglandins. They include those which prefer prostaglandin D2 (DP receptors), prostaglandin E2 (EP1, EP2, and EP3 receptors), prostaglandin F2-alpha (FP receptors), and prostacyclin (IP receptors).	Prostaglandin Receptors,Prostaglandin Receptor,Receptor, Prostaglandin,Receptors, Prostaglandins,Prostaglandins Receptors
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D001667	Binding, Competitive	The interaction of two or more substrates or ligands with the same binding site. The displacement of one by the other is used in quantitative and selective affinity measurements.	Competitive Binding
D013189	SRS-A	A group of LEUKOTRIENES; (LTC4; LTD4; and LTE4) that is the major mediator of BRONCHOCONSTRICTION; HYPERSENSITIVITY; and other allergic reactions. Earlier studies described a "slow-reacting substance of ANAPHYLAXIS" released from lung by cobra venom or after anaphylactic shock. The relationship between SRS-A leukotrienes was established by UV which showed the presence of the conjugated triene. (From Merck Index, 11th ed)	Slow Reacting Substance of Anaphylaxis
D014316	Tritium	The radioactive isotope of hydrogen also known as hydrogen-3. It contains two NEUTRONS and one PROTON in its nucleus and decays to produce low energy BETA PARTICLES.	Hydrogen-3,Hydrogen 3
D018077	Receptors, Leukotriene	Cell-surface receptors that bind LEUKOTRIENES with high affinity and trigger intracellular changes influencing the behavior of cells. The leukotriene receptor subtypes have been tentatively named according to their affinities for the endogenous leukotrienes LTB4; LTC4; LTD4; and LTE4.	Leukotriene Receptors,Receptors, SRS-A,SRS-A Receptors,Leukotriene Receptor,Receptors, Leukotrienes,SRS-A Receptor,Slow Reacting Substance of Anaphylaxis Receptors,Slow Reaction Substance of Anaphylaxis Receptors,Leukotrienes Receptors,Receptor, Leukotriene,Receptor, SRS-A,Receptors, SRS A,SRS A Receptor,SRS A Receptors