Myeloperoxidase, human white blood cells (MPO) is a peroxidase. In Myeloperoxidase, human white blood cells mediate oxidative stress by promoting the production of reactive oxygen species (ROS) and active nitrogen (RNS), regulating the polarization and inflammation-related signaling pathways of microglia and neutrophils. Myeloperoxidase, human white blood cells has antibacterial activity^[1][2].