Secretion assay
Encyclopedia
Secretion assay is a process used in cell biology
to identify cells that are secreting
a particular protein
(usually a cytokine
). It was first developed by Manz et al. in 1995.
Usually, a cell that is secreting the protein of interest is isolated using an antibody-antibody complex that coats the cell and is able to "catch" the secreted molecules. The cell is then detected by another fluorochrome-labelled antibody
, and is subsequently extracted using a process called fluorescent-activated cell sorting (FACS). The FACS method is broadly similar to the enzyme-linked immunosorbent assay (ELISA
) antibody format, except that the encapsulated cells remain intact. This is advantageous as the cells are still living after the extraction has taken place.
Further advances now mean that it is possible to extract the secreting cells using a magnetic-based separation system or using a flow cytometer.
A number of commercial applications exist for secretion assay. One such example is the Gel Microdrop (GMD) techonology, developed by One Cell Systems. One Cell asserts that GMD typically recovers a higher number of viable secreting cells than other methods, whilst ignoring any cells which are not secreting the desired protein.
Cell biology
Cell biology is a scientific discipline that studies cells – their physiological properties, their structure, the organelles they contain, interactions with their environment, their life cycle, division and death. This is done both on a microscopic and molecular level...
to identify cells that are secreting
Secretion
Secretion is the process of elaborating, releasing, and oozing chemicals, or a secreted chemical substance from a cell or gland. In contrast to excretion, the substance may have a certain function, rather than being a waste product...
a particular protein
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
(usually a cytokine
Cytokine
Cytokines are small cell-signaling protein molecules that are secreted by the glial cells of the nervous system and by numerous cells of the immune system and are a category of signaling molecules used extensively in intercellular communication...
). It was first developed by Manz et al. in 1995.
Usually, a cell that is secreting the protein of interest is isolated using an antibody-antibody complex that coats the cell and is able to "catch" the secreted molecules. The cell is then detected by another fluorochrome-labelled antibody
Antibody
An antibody, also known as an immunoglobulin, is a large Y-shaped protein used by the immune system to identify and neutralize foreign objects such as bacteria and viruses. The antibody recognizes a unique part of the foreign target, termed an antigen...
, and is subsequently extracted using a process called fluorescent-activated cell sorting (FACS). The FACS method is broadly similar to the enzyme-linked immunosorbent assay (ELISA
ELISA
Enzyme-linked immunosorbent assay , is a popular format of a "wet-lab" type analytic biochemistry assay that uses one sub-type of heterogeneous, solid-phase enzyme immunoassay to detect the presence of a substance in a liquid sample."Wet lab" analytic biochemistry assays involves detection of an...
) antibody format, except that the encapsulated cells remain intact. This is advantageous as the cells are still living after the extraction has taken place.
Further advances now mean that it is possible to extract the secreting cells using a magnetic-based separation system or using a flow cytometer.
A number of commercial applications exist for secretion assay. One such example is the Gel Microdrop (GMD) techonology, developed by One Cell Systems. One Cell asserts that GMD typically recovers a higher number of viable secreting cells than other methods, whilst ignoring any cells which are not secreting the desired protein.
External links
- One Cell Systems - Gel Microdrop (GMD) Secretion Assay techonology.
- Turcanu V, Williams NA Cell identification and isolation on the basis of cytokine secretion: a novel tool for investigating immune responses Nat Med. 2001 Mar;7(3):373-6