Immunofluorescence is an assay which is used primarily on biological samples and is classically defined as a procedure to detect antigens in cellular contexts using antibodies. The specificity of antibodies to their antigen is the base for immunofluorescence. The biological samples include tissue and cells. Immunofluorescence allows researchers to evaluate whether or not cells in a particular sample express the antigen in question. In cases where an immunopositive signal is found, immunofluorescence also allows researchers to determine which subcellular compartments are expressing the antigen. Immunofluorescence can be used on cultured cell lines, tissue sections, or individual cells.
Immunofluorescence may be used to analyze the distribution of proteins, glycans, and small biological and non-biological molecules. Immunofluorescence has been widely used in biological research and medical research yield and becomes one most important and effective method
There are two different immunofluorescence assay which include indirect immunofluorescence assay and direct immunofluorescence assay.For indirect immunofluorescence assay, the protocol mainly include tissue or tell treparation, tissue or cell fixation, serum blocking, primary antibody incubation, marked second antibody incubation, staining, result judgment and imaging. For direct immunofluorescence assay, there are only marked primary antibody been incubated without second antibody and other steps are same.