A large white blood cell, derived from monocytes (a subclass of mononuclear_leukocytes ). Properties include phagocytosis and antigen presentation to T-cells. Macrophages]] contain granules or packets of chemicals and enzymes (such as IL1 ) which serve the purpose of ingesting and destroying microbes, antigens and other foreign substances.
macrophage|Macrophages are not found in the bloodstream but at locations where body organs interface with the environment or the bloodstream. For example, in the lungs, spleen , bone marrow and liver. Similar cells in the blood are the monocytes.