Immunodetection

=Immunodetection=

**Immunodetection** is an umbrella term for the techniques used to detect specific proteins in a mixture, using complementary antibodies which are labelled for detection. Immunodetection can be performed either //in vitro// in a homogenate sample or //in vivo// in a cell or tissue.

The antibodies used in immunodetection can be monoclonal, a single antibody species derived from a clonal cell line, or polyclonal, where there is a population of different antibodies that recognise different parts of the protein. Antibodies are obtained by inoculating a mouse with an antigen, extracting immune cells and fusing them with tumour cells to produce clonal antibody-producing cell lines called //hybridomas//.

The antibodies are labelled for detection either radioactively (125I), fluorescently using FITC (green) or rhodamine (red), or by conjugation to a fluorophore or an enzyme that catalyses a bioluminescent reaction.

Techniques include:

For the //in vitro// detection of a specific protein:
 * Immuno dot blots
 * Western blotting (or immunoblotting)
 * Immunoprecipitation (also allows detection of post-translational modifications)

For the //in vivo// detection of a specific protein:
 * Immunocytochemistry
 * Immunohistochemistry

For the //in vivo// detection of protein-DNA interactions:
 * Chromatin immunoprecipitation (chIP)

For monitoring of //in vivo// protein synthesis:
 * Pulse-chase

For the //in vitro// detection of protein-protein interactions
 * GST pull-down experiments