What is immunohistochemistry (IHC)?
Immunohistochemistry is a technique used to determine the presence and level of specific cellular proteins. IHC measures protein levels using specially labeled antibodies that can bind to the proteins of interest. Samples with more protein will bind more antibody and give a stronger signal (stain). This allows the test to reveal not only whether a protein is present but also the relative amount of the protein. Test results are based on the strength of the staining and the percent of cells stained.