Immunohistochemistry (IHC) Principle

Immunohistochemistry (IHC) is a wide-used biological technique that combines anatomy, physiology, immunology and biochemistry. Developed from the antigen-antibody binding reaction, immunohistochemistry can be considered as a method that visualize distribution and localization of specific antigen or cellular components in separated tissues, or tissue sections. Compared to other bio-techniques that are based on the antigen-antibody reaction such as immunoprecipitation, or western-blot, immunohistochemistry provides in situ information which promises a more convincing experimental result.
Major components in a complete immunohistochemistry experiment:
1)Primary antibody binds to specific antigen;
2)The antibody-antigen complex is formed by incubation with a secondary, enzyme-conjugated, antibody;
3)With presence of substrate and chromogen, the enzyme catalyzes to generate colored deposits at the sites of antibody-antigen binding.