measured Protocols

Category: Cell Biology and Cell Culture: Apoptosis Protocols: Apoptosis Analysis

Analysis of DNA Fragmentation Using the JAM Assay. By Shailaja Kasibhatla et al., The JAM assay is based on labeling nuclear DNA of cycling cells with [3H]thymidine and harvesting samples on glass fiber filters. Apoptosis will generate DNA fragments small enough to pass through the glass fiber filter, resulting in decreased radioactivity of the particular sample. Cell-mediated cytotoxicity or cell killing mediated by cytotoxic T lymphocytes (CTL) can also be measured by this technique. - [Read Analysis Of DNA Fragmentation Using The JAM Assay (Subscription Required)]

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: 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+]i, in cultured adherent RAW 264.7 cells, using a 96- well plate format. This objective is accomplished by using the Ca2+-sensitive fluorescent dye, fluo-3, 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 by using a bottom read of a 96-well plate, with cells that have been washed. - [Read Assay of Intracellular Free Calcium in RAW 264.7 Cells Loaded with Fluo-3 Protocol]

Category: Immunology: B Cell Protocols

Describes the antigenic stimulation of in vitro antibody production by B cells and the subsequent measurement of secreted antibodies. The first protocol is a generalized system for inducing in vitro antibody production and can accommodate various types of antigens under study. Secreted antibodies can then be measured with an enzyme-linked immunosorbent assay (ELISA) or other soluble-antibody detection systems. - [Read Assays for B Lymphocyte Function Protocols]

Category: Fungi Protocols

Serum concentrations of itraconazole should be measured in patients receiving this drug to ensure that therapeutic concentrations are being achieved. This is necessary as drug absorption can be variable, and levels may be lowered by interactions with other drugs. The assay will give an indication of whether suitable blood levels have been achieved. - [Read Bioassay for Determining Itraconazole Levels in Blood]

Category: Pharmacology and Toxicology Protocols: Cytotoxicity Protocols: Cytotoxicity Assays in Cell Culture Protocols

The cytotoxic effect of chemicals upon cells in culture is measured by cell viability (neutral red uptake) method. - [Read Frame Modified Neutral Red Uptake Cytotoxcity Test]

Category: Pharmacology and Toxicology Protocols: Cytotoxicity Protocols: Liver Toxicity Assays Protocols

The results of cytotoxicity tests in primary cultures of rat hepatocytes and in MDBK and McCoy cells can be used to predict the in vivo 4-wk maximum tolerated dose in rats and dogs.  A correlation between in vitro cytotoxicity, as measured in this system, and LD50 values in rats and mice has also been established. - [Read In Vitro Prediction of the Maximum Tolerated Dose Protocol]

Category: Cell Biology and Cell Culture: In Vitro Reconstitution Protocols

With this protocol, transcripts that were initiated from specific genes by RNA polymerases prior to permeabilization can be measured. Instead of a nuclear extract, permeabilized cells are used. Includes information on: Permeabilization of Cells; In vitro Transcription Reaction (Run-off); Isolation of RNA; Preparation of Slot Blot Membrane for Hybridization; Hybridization of Nitrocellulose Membrane; TCA Precipitation to Determine Incorporation of [32P] GTP into Nucleic Acid - [Read In Vitro Transcription Assay (Run-off Assay) using Permeabilized Cells]

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: Pharmacology and Toxicology Protocols: Cytotoxicity Protocols: Cytotoxicity Assays in Cell Culture Protocols

The cytotoxic effect of chemicals upon mammalian cells, such as BALB/c 3T3 and HepG2, in culture is measured by highest tolerated dose (HTD), cell viability (Neutral Red) and total cell protein (coomassie blue). - [Read Neutral Red Cytotoxicity Assay Protocol]

Category: Cell Biology and Cell Culture: In Vitro Reconstitution Protocols

In this protocol nuclei isolated from cells expressing the gene of interest are incubated with radiolabeled UTP which is incorporated into nascent RNA transcripts by RNA polymerase molecules that were actively transcribing at the time the cells were harvested. Because very little denovo initiation of RNA synthesis occurs in isolated nuclei, transcription of the target gene can be measured by hybridizing the radiolabeled RNA to an excess of the target gene immobilized on a nitrocellulose or nylon - [Read Protocol for Transcriptional Run- On Assays]

Category: Fungi Protocols

Serum concentrations of voriconazole should be measured in patients receiving this drug to ensure that therapeutic levels are being achieved. The assay will give an indication of whether suitable blood levels have been achieved. - [Read Protocol: Bioassay for Determining Voriconazole Levels in Blood]

Category: Immunology: T Cell Protocols

In the first protocol, IL-2-producing murine T cells are measured following stimulation by the mitogen Con A. The second protocol provides a modification for using human responder cells. The second protocol is used for estimating the proportion of cells that can generate a clone of cytotoxic effector cells when stimulated by Con A with the addition of IL-2. - [Read Quantitation of Functional T Cells by Limiting Dilution Protocols]

Category: Pharmacology and Toxicology Protocols: Cytotoxicity Protocols: Cell Specific Cytotoxicity Assays Protocols

An in vitro red blood cell assay is presented which allows the estimation of the irritation potential of tensides and tenside containing materials such as shampoos, shower gels, cleaning products, etc. The estimation is based on the fact that surfactants interact strongly with cellular membranes and proteins.  Both effects are measured photometrically by use of the inherent native dye, oxyhemoglobin. - [Read Red Blood Cell Test System Protocol]

Category: Pharmacology and Toxicology Protocols: Cytotoxicity Protocols: Cytotoxicity Assays in Cell Culture Protocols

Rabbit-derived corneal cells are cultured in the presence of test compounds, the toxicity of which are determined by their effect upon cell viability.  A decrease in cell number, as measured by uptake of the dye Neutral Red, serves as an indicator of potential cytotoxicity.  This test has been proposed as a potential replacement alternative for the Draize Eye Irritation test. - [Read SIRC Cytotoxcitiy Test]

Category: Reporter Gene Assays: Luciferase Assay Protocols

Protocol describes a split luciferase complementation assay used to study the interaction of proteins in cells. In the split protein strategy, a single reporter protein/enzyme (firefly luciferase [Fluc]) is cleaved into amino-terminal and carboxy-terminal halves; each half is fused to one of two interacting proteins, X & Y. Physical interactions between the two proteins reconstitute the functional reporter protein, leading to enzymatic activities that can be measured by in vitro or in vivo assay - [Read Split Luciferase Complementation Assay for Studying Interaction of Proteins X and Y in Cells]

Category: Pharmacology and Toxicology Protocols: Cytotoxicity Protocols: Cytotoxicity Assays in Cell Culture Protocols

The cytotoxic effect of chemicals upon cells in culture is measured by the change in total cell protein arising from the inhibition of cell proliferation (Kenacid Blue R dye binding method). - [Read The Frame Cytotoxicity Test Kenacid Blue]

Category: Plant Biology Protocols: Plant DNA RNA Isolation Protocols

During development many plant cells undergo endoreduplication, whereby ploidy increases to a multiple of the normal 2C content. For eg., trichome development is accompanied by an increase in ploidy to 32C, indicating that trichome cells undergo four rounds of endoreduplication. Protocol describes DNA levels, and hence developmental progress in the corresponding cells, are measured by staining the DNA with a fluorescent marker and then quantifying the fluorescence of individual nuclei. - [Read Whole-Mount DAPI Staining and Measurement of DNA Content in Plant Cells]