Aggregation of IgE receptors induces degranulation in rat basophilic leukemia cells permeabilized with alpha-toxin from Staphylococcus aureus

摘要: Abstract A method has been developed by which rat basophilic leukemia (RBL) cells can be permeabilized to small molecules while maintaining their ability degranulate in response aggregation of IgE receptors. alpha-Toxin was isolated from culture supernatants Staphylococcus aureus precipitation with (NH4)2SO4 and chromatography on phenyl-Sepharose. The toxin binds the plasma membrane RBL polymerizes form a transmembrane pore that allows (Mr less than 1000), but not macromolecules, diffuse freely across membrane. There no spontaneous release contents cell secretory granules during permeabilization or subsequent incubations. Substantial receptor-mediated exocytosis occurred absence Ca2+, degranulation maximal at 0.1-1.0 microM physiologically important range Ca2+ concentrations. Using these cells, (i.e., substrates inhibitors various enzymes) normally excluded introduced into cell. Moreover, intracellular concentration ions (such as Ca2+) precisely controlled. This will allow detailed examination individual biochemical events involved mast cells.