Biomaterial Database

Kinetics of pinocytosis studied by flow cytometry. 1984

B van Deurs, and C Röpke, and N Thorball

Kinetics of pinocytosis of FITC-Dextran (mw 70 000) was analysed in mouse L-cells using flow cytometry with a fluorescence-activated cell sorter (FACS). In each experiment information on 2 X 10(4) individual, living cells was obtained. The population of L-cells thus analysed was shown to be rather homogeneous with respect to cell size, and the peak of the FITC-fluorescence curve--a histogram of the accumulated signals from L-cells exposed to FITC-Dextran--was shown to be representative of the average size of the L-cells. It was found that the cellular accumulation of FITC-Dextran was proportional to the tracer. However, the rate of accumulation decreased with increasing time of incubation (up to 3 h). When cells were pulse-labeled for 10 min at 37 degrees C, rinsed carefully with ice-cold PBS, and reincubated at 37 degrees C for various periods of time, about 50% of the initial cellular FITC-fluorescence disappeared within approximately 15 min of reincubation, whereafter no measurable decrease in cellular fluorescence was seen. In addition, a rapid increase of intact FITC-Dextran molecules in the reincubation medium occurred within the first 15 to 30 min of reincubation, whereafter no further increase took place. Thus, a large portion of previously endocytosed FITC-Dextran becomes rapidly exocytosed, while the rest becomes sequestered within a compartment from where little or no exocytosis occurs. The deviation from linearity in accumulation related to time, and the distinct biphasic kinetics of exocytosis are taken to support a generalized two-compartment model for endocytosis and membrane recycling, the two compartments being endocytic vacuoles (endosomes) and (secondary) lysosomes, respectively.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D007739	L Cells	A cultured line of C3H mouse FIBROBLASTS that do not adhere to one another and do not express CADHERINS.	Earle's Strain L Cells,L Cell Line,L Cells (Cell Line),L-Cell Line,L-Cells,L-Cells, Cell Line,L929 Cell Line,L929 Cells,NCTC Clone 929 Cells,NCTC Clone 929 of Strain L Cells,Strain L Cells,Cell Line L-Cell,Cell Line L-Cells,Cell Line, L,Cell Line, L929,Cell Lines, L,Cell, L,Cell, L (Cell Line),Cell, L929,Cell, Strain L,Cells, L,Cells, L (Cell Line),Cells, L929,Cells, Strain L,L Cell,L Cell (Cell Line),L Cell Lines,L Cell, Strain,L Cells, Cell Line,L Cells, Strain,L-Cell,L-Cell Lines,L-Cell, Cell Line,L929 Cell,Strain L Cell
D008954	Models, Biological	Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.	Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
D010873	Pinocytosis	The engulfing of liquids by cells by a process of invagination and closure of the cell membrane to form fluid-filled vacuoles.	Pinocytoses
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
D005434	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.	Cytofluorometry, Flow,Cytometry, Flow,Flow Microfluorimetry,Fluorescence-Activated Cell Sorting,Microfluorometry, Flow,Cell Sorting, Fluorescence-Activated,Cell Sortings, Fluorescence-Activated,Cytofluorometries, Flow,Cytometries, Flow,Flow Cytofluorometries,Flow Cytofluorometry,Flow Cytometries,Flow Microfluorometries,Flow Microfluorometry,Fluorescence Activated Cell Sorting,Fluorescence-Activated Cell Sortings,Microfluorimetry, Flow,Microfluorometries, Flow,Sorting, Fluorescence-Activated Cell,Sortings, Fluorescence-Activated Cell
D005452	Fluoresceins	A family of spiro(isobenzofuran-1(3H),9'-(9H)xanthen)-3-one derivatives. These are used as dyes, as indicators for various metals, and as fluorescent labels in immunoassays.	Tetraiodofluorescein
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
D000941	Antigens	Substances that are recognized by the immune system and induce an immune reaction.	Antigen
D016650	Fluorescein-5-isothiocyanate	Fluorescent probe capable of being conjugated to tissue and proteins. It is used as a label in fluorescent antibody staining procedures as well as protein- and amino acid-binding techniques.	FITC,5-Isothiocyanatofluorescein,Fluorescein (5 or 6)-Isothiocyanate,Fluorescein-5-isothiocyanate Hydrochloride,5 Isothiocyanatofluorescein,Fluorescein 5 isothiocyanate,Fluorescein 5 isothiocyanate Hydrochloride,Hydrochloride, Fluorescein-5-isothiocyanate