Biomaterial Database

Regulation of the release of eosinophil cationic protein by eosinophil adhesion. 2000

X Xu, and L Håkansson

Department of Medical Sciences, Clinical Chemistry, University Hospital, Uppsala, Sweden.

BACKGROUND Varying release of eosinophil granule proteins depending on the stimulus and environmental factors has previously been reported. OBJECTIVE To investigate the degranulation from adherent eosinophils by using mixed granulocytes. METHODS Granulocytes isolated by Percoll gradient centrifugation were incubated on plates coated with plasma and tissue fibronectin, fibrinogen or human serum albumin (HSA) and stimulated with Mn2+, phorbol-myristate-acetate (PMA), formyl-methionyl-leucyl-phenylalanine (f-MLP) and combinations thereof, respectively. The release of eosinophil cationic protein (ECP) was measured by radioimmunoassay. RESULTS Unstimulated eosinophils incubated in wells coated with plasma and tissue fibronectin, fibrinogen or HSA did not release any ECP. Furthermore, Mn2+ (5 mmol/L) did not induce release of ECP despite the fact that adhesion of eosinophils to these four proteins was induced. PMA stimulated a dose-dependent release of ECP. Contemporaneous stimulation of eosinophils with PMA and Mn2+ induced a dramatically increased release of ECP regardless of which protein the eosinophils were adhering to. A small but significant release of ECP was found when eosinophils incubated on plates coated with fibrinogen and HSA were stimulated by f-MLP. Contemporaneous stimulation of eosinophils with f-MLP and Mn2+ did not induce any synergistic effect on the release of ECP. On the contrary, Mn2+ inhibited the release of ECP induced by f-MLP from eosinophils. Serum-opsonized Sephadex particles stimulated a potent increase of the release of ECP up to 12%-14% in the presence of plasma fibronectin and, in particular, fibrinogen. The kinetics of eosinophil adhesion and degranulation showed that the cellular adhesion preceded the degranulation response and that the degranulation patterns depend on the stimuli and environment. CONCLUSIONS The present study indicated that cellular adhesion plays an important role in the regulation of eosinophil degranulation, but that adhesion and degranulation can be induced separately.

UI	MeSH Term	Description	Entries
D008345	Manganese	A trace element with atomic symbol Mn, atomic number 25, and atomic weight 54.94. It is concentrated in cell mitochondria, mostly in the pituitary gland, liver, pancreas, kidney, and bone, influences the synthesis of mucopolysaccharides, stimulates hepatic synthesis of cholesterol and fatty acids, and is a cofactor in many enzymes, including arginase and alkaline phosphatase in the liver. (From AMA Drug Evaluations Annual 1992, p2035)
D009240	N-Formylmethionine Leucyl-Phenylalanine	A formylated tripeptide originally isolated from bacterial filtrates that is positively chemotactic to polymorphonuclear leucocytes, and causes them to release lysosomal enzymes and become metabolically activated.	F-Met-Leu-Phe,N-Formyl-Methionyl-Leucyl-Phenylalanine,Formylmet-Leu-Phe,Formylmethionyl Peptide,Formylmethionyl-Leucyl-Phenylalanine,Formylmethionylleucylphenylalanine,N-Formylated Peptide,N-formylmethionyl-leucyl-phenylalanine,fMet-Leu-Phe,F Met Leu Phe,Formylmet Leu Phe,Formylmethionyl Leucyl Phenylalanine,Leucyl-Phenylalanine, N-Formylmethionine,N Formyl Methionyl Leucyl Phenylalanine,N Formylated Peptide,N Formylmethionine Leucyl Phenylalanine,N formylmethionyl leucyl phenylalanine,Peptide, Formylmethionyl,Peptide, N-Formylated,fMet Leu Phe
D009895	Opsonin Proteins	Proteins that bind to particles and cells to increase susceptibility to PHAGOCYTOSIS, especially ANTIBODIES bound to EPITOPES that attach to FC RECEPTORS. COMPLEMENT C3B may also participate.	Opsonin,Opsonin Protein,Opsonins,Protein, Opsonin
D001798	Blood Proteins	Proteins that are present in blood serum, including SERUM ALBUMIN; BLOOD COAGULATION FACTORS; and many other types of proteins.	Blood Protein,Plasma Protein,Plasma Proteins,Serum Protein,Serum Proteins,Protein, Blood,Protein, Plasma,Protein, Serum,Proteins, Blood,Proteins, Plasma,Proteins, Serum
D002448	Cell Adhesion	Adherence of cells to surfaces or to other cells.	Adhesion, Cell,Adhesions, Cell,Cell Adhesions
D003911	Dextrans	A group of glucose polymers made by certain bacteria. Dextrans are used therapeutically as plasma volume expanders and anticoagulants. They are also commonly used in biological experimentation and in industry for a wide variety of purposes.	Dextran,Dextran 40,Dextran 40000,Dextran 70,Dextran 75,Dextran 80,Dextran B-1355,Dextran B-1355-S,Dextran B1355,Dextran B512,Dextran Derivatives,Dextran M 70,Dextran T 70,Dextran T-40,Dextran T-500,Hemodex,Hyskon,Infukoll,Macrodex,Polyglucin,Promit,Rheodextran,Rheoisodex,Rheomacrodex,Rheopolyglucin,Rondex,Saviosol,Dextran B 1355,Dextran B 1355 S,Dextran T 40,Dextran T 500
D004804	Eosinophils	Granular leukocytes with a nucleus that usually has two lobes connected by a slender thread of chromatin, and cytoplasm containing coarse, round granules that are uniform in size and stainable by eosin.	Eosinophil
D005786	Gene Expression Regulation	Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.	Gene Action Regulation,Regulation of Gene Expression,Expression Regulation, Gene,Regulation, Gene Action,Regulation, Gene Expression
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia