summary: Antibodies are used to identify specific proteins usually in fixed specimens.
Antibodies are proteins produced by the immune system that recognize proteins from foreign organisms (infections etc) and tell the immune system to attack the infection. To make antibodies to a specific protein, the purified protein is injected into animals (often rabbits or mice) and they produce antibodies that can be collected in the blood of the injected animal. The serum is then purified to remove non-specific antibodies that don’t bind to the injected protein. These purified antibodies can be used for a variety of techniques including immunofluorescence
Ab-specific Immunofluorescence Labeling:
To observe one’s favorite protein (e.g.: a protein called tubulin, the protein that makes up microtubulesG) in C. elegans‘ embryo, one can inject tubulin into animals (rabbits, mice or —) to produce anti-tubulin antibodies. With anti-tubulin antibodies, the amount and localization of tubulin can be detected in C. elegans embryos. Below is a flash movie showing the expression of 2 proteins (tubulin & syntaxin-4) using antibody-specific immunofluorescence labeling.