Immunohistochemistry, Immunocytochemistry, and Immunofluorescence are three commonly used applications in biology, with their English names being Immunohistochemistry (IHC), Immunocytochemistry (ICC), and Immunofluorescence (IF).
Root meanings:
Immuno- refers to immune techniques (for example, the binding of antibodies and antigens).
Histo- refers to tissues (cells and their surrounding extracellular matrix).
Cyto- refers to cells (excluding the extracellular matrix).
Chemistry- here refers to chemical detection methods (for example, color changes).
Fluorescence- refers to the detection of excited fluorophores.
Immunohistochemistry (IHC) involves labeling cellular proteins in tissue samples using specific primary antibodies and visualizing the targets with detection reagents. IHC can assess protein expression through chromogenic detection or fluorescence detection. Both detection systems rely on antigen recognition mediated by primary antibodies. Chromogenic IHC utilizes enzyme-catalyzed deposition of chromogens at the antigen location, while fluorescent IHC employs fluorophores to assist in visualizing the target antigens through direct or indirect immunofluorescence methods.
Immunocytochemistry is a detection technique that combines cytochemical techniques with immunological techniques. Based on the specific recognition of antigens and antibodies, it specifically detects the presence and distribution of peptides, proteins, and other substances on the cell surface or within cells using specific chemical chromogenic or fluorescent substances.
IHC and ICC are easily distinguishable in Chinese, as one application uses tissue samples (IHC), while the other uses cell samples (ICC). However, once fluorescence labeling is used, it seems that people become unsure about which to use, because immunofluorescence refers to the use of fluorescent labeling, making it easy to simply write one IF without specifying whether it is tissue (IHC) or cells (ICC).
In summary, both IHC and ICC are techniques used to localize and detect antigen expression. IHC applies to tissue sections, while ICC applies to adherent or suspended cells. Both first fix the samples to maintain cell integrity, followed by incubation with blocking reagents to cover non-specific binding sites that antibodies might attach to. Finally, primary and secondary antibodies are incubated to detect the sample, and the signal results are observed under a microscope.
Welcome to follow the Lab Family public account: labfamily
Or scan the QR code below:
