Biomaterial Database

Plasminogen activator of guinea pig basophilic leukocytes: probable localization to the plasma membrane. 1978

H F Dvorak, and N S Orenstein, and J Rypysc, and R B Colvin, and A M Dvorak

The plasminogen activator (PA) activity of guinea pig basophil-enriched leukocyte preparations was localized to basophils, and not to contaminating lymphocytes and eosinophils, by correlating PA activity with basophil frequency and, more directly, by means of an improved cytochemical method here described. PA activity was fully expressed in living cells in the absence of immunologic stimuli and was suppressed/lost to a variable extent by different techniques of cell disruption. Conversely, killed, but not living, basophils expressed significant plasminogen-independent fibrinolytic activity, presumably reflecting access of cytoplasmic proteases of broken basophils to fibrin substrate. The PA activity of intact cells was destroyed by gentle trypsinization under conditions that did not impair cell viability. When disrupted cells were ultracentrifuged on a sucrose density gradient, PA activity was absent from purified granules and was confined to fractions containing cell membranes. The simplest explanation of these data is that guinea pig basophils have PA activity associated with their plasma membranes. This conclusion has several important implications for basophil functions in cell-mediated and other immunologic reactions in vivo.

UI	MeSH Term	Description	Entries
D010960	Plasminogen Activators	A heterogeneous group of proteolytic enzymes that convert PLASMINOGEN to FIBRINOLYSIN. They are concentrated in the lysosomes of most cells and in the vascular endothelium, particularly in the vessels of the microcirculation.	Extrinsic Plasminogen Activators,Plasminogen Activator,Uterine-Tissue Plasminogen Activator,Uterine Tissue Plasminogen Activator
D002462	Cell Membrane	The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.	Plasma Membrane,Cytoplasmic Membrane,Cell Membranes,Cytoplasmic Membranes,Membrane, Cell,Membrane, Cytoplasmic,Membrane, Plasma,Membranes, Cell,Membranes, Cytoplasmic,Membranes, Plasma,Plasma Membranes
D002469	Cell Separation	Techniques for separating distinct populations of cells.	Cell Isolation,Cell Segregation,Isolation, Cell,Cell Isolations,Cell Segregations,Cell Separations,Isolations, Cell,Segregation, Cell,Segregations, Cell,Separation, Cell,Separations, Cell
D005342	Fibrinolysis	The natural enzymatic dissolution of FIBRIN.	Fibrinolyses
D006651	Histocytochemistry	Study of intracellular distribution of chemicals, reaction sites, enzymes, etc., by means of staining reactions, radioactive isotope uptake, selective metal distribution in electron microscopy, or other methods.	Cytochemistry
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
D001491	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.	Basophil
D014357	Trypsin	A serine endopeptidase that is formed from TRYPSINOGEN in the pancreas. It is converted into its active form by ENTEROPEPTIDASE in the small intestine. It catalyzes hydrolysis of the carboxyl group of either arginine or lysine. EC 3.4.21.4.	Tripcellim,Trypure,beta-Trypsin,beta Trypsin
D051379	Mice	The common name for the genus Mus.	Mice, House,Mus,Mus musculus,Mice, Laboratory,Mouse,Mouse, House,Mouse, Laboratory,Mouse, Swiss,Mus domesticus,Mus musculus domesticus,Swiss Mice,House Mice,House Mouse,Laboratory Mice,Laboratory Mouse,Mice, Swiss,Swiss Mouse,domesticus, Mus musculus