MPO is usually stored in a certain type of white blood cell. These cells release MPO when blood vessels are injured or become inflamed. Myeloperoxidase (MPO) is an unequivocal marker of myeloid differentiation which is routinely detected using cytochemistry (CC), flow cytometry (FC) and immunohistochemistry (IH).
Immunohistochemistry is a more sensitive marker for the detection of myeloperoxidase in acute myeloid leukemia compared with flow cytometry and cytochemistry. IHC takes its name from the roots 'immuno', in reference to antibodies used in the procedure, and 'histo,' which means “tissue”. Immunohistochemistry is also widely used in basic research to understand the distribution and localization of biomarkers and differentially expressed proteins in different parts of a biological tissue.