Description
Protocol
Available protocols: Functional
Background
Cell death can occur either by apoptosis, a highly regulated biochemical pathway involving signal transduction cascades, or by necrosis. Necrosis is accompanied by mitochondrial swelling and increased plasma membrane permeability, while apoptosis involves an articulated breakdown of the cell into membrane-bound apoptotic bodies (1). There are a number of assays that are designed to measure cytotoxicity and cell death, independent of mechanism. Most of these assays assess cell viability by measuring plasma membrane permeability (2). Lactate dehydrogenase (LDH) is a stable, soluble enzyme located in the cytosol of many different cell types. The enzyme is released into the surrounding culture medium upon plasma membrane damage. LDH activity in the culture medium can, therefore, be used as a reliable indicator of cell membrane integrity, and thus a measurement of cytotoxicity.
