extracellular Protocols

Category: Cell Biology and Cell Culture: Endothelial Cell Protocols

Traditional animal models to quantify the degree of blood vessel formation are being replaced by cell culture assays that are easier to set up, statistically reliable and can be automated in a drug screening laboratory. These assays rely on the endothelial cells’ ability to form distinct blood-vessel-like tubules in an extracellular matrix where they can subsequently be visualized by fluorescence microscopy. - [Read An Image-Based Assay of Endothelial Cell Tube Formation as a Model of Angiogenesis]

Category: Cell Biology and Cell Culture: Flow Cytometry Protocols: Intracellular Ion Measurement Protocols

This protocol describes a method to assess concentrations of free cytoplasmic calcium (Ca2+) in cultured RAW 264.7 cells. This objective is accomplished with the Ca2+-sensitive fluorescent dye, fluo-3, which permeates cells as an ester and is hydrolyzed in the cell to its Ca2+-sensitive acidic form. Fluorescence is measured over time with adherent cells that have been washed free of extracellular dye. - [Read Assay of Intracellular Free Calcium in RAW 264.7 Cells for Ligand Screen Protocol]

Category: Bacterial Cell Culture Protocols

The growth conditions of microbial cell cultures and the time of sample collection should be optimized and standardized when growing cells for protein extraction. Because cells may excrete proteases and other extracellular enzymes, and compounds in the medium may interfere with extraction, wash cultures with an isotonic buffer, such as PBS or sucrose before solubilization. - [Read Extraction and Solubilization of Total Protein from Microorganisms Protocol]

Category: Signalling Signal Transduction Protocols

This protocol assays inhibition of in vivo binding of [3H]-cAMP to cAR1 by GTPγS. Dictyostelium discoideum respond to extracellular cAMP through the cAMP chemoattractant receptor (cAR1). Binding of cAMP to the G protein-coupled cAR1 is inhibited by the GTP analog GTPγS. Protocol includes information on: Solutions used, BioReagents and Chemicals and Protocol Hints. - [Read GTPγS-Induced Inhibition of cAMP Binding to the cAMP Receptor (cAR1) in Dictyostelium Discoideum]

Category: Pharmacology and Toxicology Protocols: Drug Discovery

Protocol describes an assay that relies on the endothelial cells’ ability to form distinct blood-vessel-like tubules in an extracellular matrix  where they can subsequently be visualized by fluorescence microscopy.  Although quantification of the tubules can be performed by manual tracing, this method precludes the use of the assay in unbiased high-throughput applications. - [Read Image Based Assay of Endothelial Cell Tube Formation Protocol]

Category: Molecular Biology Protocols: Carbohydrate Protocols

Indirect method measuring immunofluorescence coupled to second antibody. Best for membrane antigens in addition to intra- and extracellular antigens, may be applied to frozen tissue sections, to cells in suspension, and to cells attached to glass slides or coverslips. Tadashi Tai~Head, Department of Tumor Immunology, The Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan - [Read Immunohistochemistry using Anti-Ganglioside Antibodies]

Category: Microscopy Protocols: Live-Cell Imaging Protocols

This protocol describes a method to assess concentrations of free cytoplasmic calcium, [Ca2+]i, for cultured adherent RAW 264.7 cells in an 8-well coverglass. This objective is accomplished using the Ca2+-sensitive fluorescent dye, fura-2 acetoxymethyl (AM), which permeates cell membranes as an ester and is hydrolyzed in the cell to its Ca2+-sensitive acidic form. Fluorescence for the adherent cells is measured over time with cells that have been washed free of extracellular dye. - [Read Live Single-Cell Fura-2 Measurements to Determine the Intracellular Free Calcium]

Category: Signalling Signal Transduction Protocols: MAPK Protocols

This protocol uses mitogen-activated protein/ERK kinase (MEK) to activate the extracellular-signal-regulated (Erk) mitogen-activated protein (MAP) kinases upon agonist binding to receptors. Protocol includes information about: Harvest, Immunoprecipitation and Kinase Reaction. Also includes following solutions: Laemmli Sample Buffer (1X), ATP Mix, Kinase Buffer (10X), Lysis Buffer. Helpful protocol hints are also included. - [Read Raf-1 Kinase Assay]

Category: Transfection Protocols: Transient Transfection Protocols

Transient transfection into 293T cells is a convenient way to overexpress and obtain both cellular and extracellular (secreted or membrane) proteins. 293 is a human renal epithelial cell line which is transformed by adenovirus E1A gene product. 293T is a derivative which also express SV40 large T antigen, allowing episomal replication of plasmids containing the SV40 origin and early promoter region. They (both) have the unusual property of being highly transfectable. - [Read Transient Transfection Into 293T Cells Protocol]