Anti-MPO antibodies are essential reagents in flow cytometry for detecting the target protein, myeloperoxidase. MPO is an enzyme that produces antimicrobial hypochlorous acid as part of the host defense system of polymorphonuclear leukocytes, including neutrophils. The 150-kDa MPO protein is a cationic heterotetramer localized to cellular lysosomes. Examine the supplier's provided validation data when comparing MPO antibodies for flow cytometry. Also look for application-specific recommendations, such as dilutions, protocols, sample types, and other helpful usage notes.