Is LDH release a good measure for cytotoxicity?

The CyQUANT LDH Cytotoxicity Assay is a colorimetric assay that provides a simple and reliable method for determining cellular cytotoxicity. Lactate dehydrogenase (LDH) is a cytosolic enzyme present in many different cell types that is released into the cell culture medium upon damage to the plasma membrane.

How does LDH cytotoxicity assay work?

The LDH assay protocol is based on an enzymatic coupling reaction: LDH released from the cell oxidizes lactate to generate NADH, which then reacts with WST to generate a yellow color. Cells can be cultured in regular 10% serum containing medium; no reducing serum or special medium is required for the assay.

What is an LDH activity assay?

Cells release LDH into the bloodstream after tissue damage or red blood cell hemolysis. The LDH Activity Assay kit quantifies LDH activity in variety of biological samples. The assay is quick, convenient, and sensitive. In this kit, LDH reduces NAD to NADH, which is specifically detected by colorimetric (450 nm) assay.

How 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.

How is cytotoxicity detected?

Loading target cells with an artificial measurable marker such as pro-fluorescent Calcein-AM (12) or radioactive 51Cr (13) has been used to measure cytotoxicity, mostly for assays that involve mixtures of more than one cell type (e.g. effector and target cells in antibody dependent cell mediated cytotoxicity assays).

Why do damaged tissues release LDH?

LDH is a type of protein, known as an enzyme. LDH plays an important role in making your body’s energy. When these tissues are damaged, they release LDH into the bloodstream or other body fluids. If your LDH blood or fluid levels are high, it may mean certain tissues in your body have been damaged by disease or injury.

Why is LDH released in tissue damage?

LDH is a soluble cytoplasmic enzyme that is present in almost all cells and is released into extracellular space when the plasma membrane is damaged (9). In the first step, LDH produces reduced nicotinamide adenine dinucleotide (NADH) when it catalyzes the oxidation of lactate to pyruvate.

What is cell viability and cytotoxicity?

Cell viability and cytotoxicity assays measure cellular or metabolic changes associated with viable or nonviable cells. These assays can detect structural changes such as loss of membrane integrity upon cell death or physiological and biochemical activities indicative of living cells.

How stable is LDH?

Serum specimens stored at 25 degrees C and -20 degrees C retained 74% and 87% of total activity after 45 days of storage. LD-1 was stable at all three temperatures, with a maximum loss of 10%.

Why is LDH released during tissue damage?

Upon tissue damage, the cells release LDH in the bloodstream. Depending upon the type of tissue injury, the enzyme can remain elevated for up to 7 days in the bloodstream. The elevated LDH in serum as a result of organ destruction occurs due to significant cell death that results in loss of cytoplasm.

Why cytotoxicity assay is performed?

Cytotoxicity assays measure loss of some cellular or intercellular structure and/or functions, including lethal cytotoxicity. They thus give an indication of the potential to cause cell and tissue injury and as such have been used by some investigators to predict tissue injury, including eye injury.

What is an LDH cytotoxicity assay?

CytoScan™ LDH Cytotoxicity Assay is a colorimetric method of assaying cellular cytotoxicity. The assay can be used with different cell types for assaying cell mediated cytotoxicity as well as cytotoxicity mediated by chemicals and other test compounds.

What is LDH in cell culture?

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.

What is the role of LDH as a cell death marker?

Since this only happens when cell membrane integrity is compromised, the presence of this enzyme in the culture medium can be used as a cell death marker. The relative amounts of live and dead cells within the medium can then be quantitated by measuring the amount of released LDH using a colorimetric or fluorometric LDH cytotoxicity assay.

How do you measure cell viability with lactate dehydrogenase?

Analysis of Cell Viability by the Lactate Dehydrogenase Assay. A common method for determining cytotoxicity is based on measuring the activity of cytoplasmic enzymes released by damaged cells. Lactate dehydrogenase (LDH) is a stable cytoplasmic enzyme that is found in all cells.