What is chromium release assay?
Abstract. The chromium-release assay developed in 1968 is still the most commonly used method to measure cytotoxicity by T cells and by natural killer cells. Target cells are loaded in vitro with radioactive chromium and lysis is determined by measuring chromium in the supernatant released by dying cells.
How to calculate specific lysis?
The percentage of specific lysis for each well was calculated as follows: % specific lysis = 100 – ((CFSE low/CFSE high) in the presence of effector cells / mean of the three wells containing target cells alone in the absence of effector cells) x100.
What is Chromium 51 used for?
A synthetic radioactive isotope of chromium having a half-life of 27.7 days and decaying by electron capture with emission of γ rays (0.32 MeV); it is used to label red blood cells for measurement of mass or volume, survival time, and sequestration studies, for the diagnosis of gastrointestinal bleeding, and to label …
What is cd107?
Recently, lysosomal-associated membrane protein-1 (LAMP-1 or CD107a) has been described as a marker of CD8+ T-cell degranulation following stimulation. Here we describe CD107a as a marker of NK cell functional activity using multi-parameter flow cytometry.
What is MTT cytotoxicity assay?
The MTT assay is used to measure cellular metabolic activity as an indicator of cell viability, proliferation and cytotoxicity. It is a quantitative assay that allows rapid and convenient handling of a high number of samples.
What is the principle of MTT assay?
The MTT assay is a colorimetric assay for measuring cell metabolic activity. It is based on the ability of nicotinamide adenine dinucleotide phosphate (NADPH)-dependent cellular oxidoreductase enzymes to reduce the tetrazolium dye MTT to its insoluble formazan, which has a purple color (Fig. 10.1).
What is the use of gold 198?
Gold-198 seeds are used in permanent seed implant therapy involving injecting approximately 30-100 radioactive seeds into the prostate gland. They give off their radiation at a low dose rate over several weeks, and then the seeds can remain in the prostate gland permanently.
How is iron 59 used for diagnosis?
From the intestine, iron is transported on transferrin to the liver or the bone marrow. iron 59 a radioisotope of iron having a half-life of 44.5 days; used in ferrokinetics tests to determine the rate at which iron is cleared from the plasma and incorporated in red blood cells.
Is CD107a a surface marker?
In particular, CD107a/LAMP-1 has been widely used as a marker for degranulating cytotoxic lymphocytes, because surface expression is induced upon degranulation. CD107a is a highly glycosylated protein comprising a 40-kDa backbone with predicted 17 N-glycosylation and 9 O-glycosylation sites.
What is degranulation assay?
A degranulation assay is based on flow cytometry, an thus this test can be combined with cellular phenotyping and analysis of effector molecule production (both cytokines and cytolytic components), for example, during characterization.
What is the 51 Cr release assay?
During the 1960s a sensitive in vitro assay, the 51 Cr-release assay, was developed to measure the ability of T lymphocytes from immunized mice to kill allogeneic tumor cells (labeled with the 51 Cr radioisotope) (Brunner et al., 1968).
How do you do a Chromium release assay?
But before you start your assay, be sure to read up on proper safety measures when handling radioactive materials. To do a chromium release assay, you first incubate your target cells (T) with 51 Cr. You then incubate the target cells with effector cells (your T cells; E).
How can I detect Cr51 in human cells?
Either Gamma or Beta Counting can be used for Cr51 detection. Spontaneous Release: Target cells without Effector cells. Incubate Target cells with an equal volume of media or buffer only. Maximum Release : Incubate Target cells with media or buffer containing 1-2% detergent to completely lyse Target cells (e.g. SDS, Triton X-100).
What is a real-time cytotoxicity assay?
A Real-Time Cytotoxicity Assay as an Alternative to the Standard Chromium-51 Release Assay for Measurement of Human NK and T Cell Cytotoxic Activity This unit describes the monitoring and quantification of cellular cytotoxicity using a non-radioactive and real-time cytotoxic assay.