How does a chromium release assay work?
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 do you 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.
How is a cytotoxicity assay done?
A frequent use of cells in culture is for a commonly used cytotoxicity assay where cells are exposed to a test compound and after some period of incubation, a marker is measured to reflect the number of viable cells present compared to positive (toxin) and negative (vehicle) control treatments.
What is toxic to cells?
Cytotoxicity is the quality of being toxic to cells. Examples of toxic agents are an immune cell or some types of venom, e.g. from the puff adder (Bitis arietans) or brown recluse spider (Loxosceles reclusa).
Why is LDH released?
Lactate dehydrogenase (LDH) is a stable cytoplasmic enzyme that is found in all cells. LDH is rapidly released into the cell culture supernatant when the plasma membrane is damaged, a key feature of cells undergoing apoptosis, necrosis, and other forms of cellular damage.
Why is LDH release a good measure for cytotoxicity?
This LDH cytotoxicity assay is capable of detecting low level damage to cell membrane which cannot detected using other methods. And since it does not damage healthy cells, the LDH cytotoxicity assay can be performed directly in the cell culture wells containing a mixed population of viable and damaged cells.
What is the principle of the 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.
What is a 51 Cr release assay?
Chromium-51 ( 51 Cr) release assays are commonly used for the precise and accurate quantification of cytotoxicity, particularly in the study of tumor and viral cytolysis. The assay is used to determine the number of lymphocytes produced in response to infection or drug treatment. A brief overview of the assay principle is illustrated below.
What is Chromium-51 (51 Cr) release?
Chromium-51 (51 Cr) release assays are commonly used for the precise and accurate quantification of cytotoxicity, particularly in the study of tumor and viral cytolysis. The assay is used to determine the number of lymphocytes produced in response to infection or drug treatment. A brief overview of the assay principle is illustrated below.
What is the principle of the Chromium release assay?
Principle of the chromium release assay. The procedure can be divided into 3 main steps: 51 Cr labeling the target cell, release of the 51 Cr label by cytolysis, and detection of the released 51 Cr label. What do I need to run this assay?
How can I isolate the 51 CR label from target cells?
Target cells are labeled with 51 Cr, the label is then released from the target cells by cytolysis. The label can be isolated by centrifuging the samples and collecting the supernatants.