Mononuclear Phagocytes and the Complement System

Mononuclear phagocytes are white blood cells with a single, un-lobed nucleus that defend the body by phagocytosis — engulfing and digesting pathogens and cellular debris. This group includes circulating monocytes, the macrophages that monocytes mature into once they migrate into tissues, and specialised, tissue-resident macrophages such as Kupffer cells in the liver and microglia in the brain — together forming a widely distributed surveillance-and-clean-up network throughout the body. …