{"type":"root","children":[{"type":"paragraph","children":[{"type":"text","value":"Macrophages comprise many forms of mononuclear phagocytes found in tissues that derive from hematopoietic stem cells in the bone marrow. Among the functions of macrophages are nonspecific phagocytosis and pinocytosis, killing of ingested microorganisms, and digestion and presentation of antigens to T and B-lymphocytes. Macrophages work to secrete a large number of diverse products such as lysozyme and collagenases, several complement components and coagulation factors, some prostaglandins and leukotrienes, and many regulatory molecules (Interferon, Interleukin 1)."}]},{"type":"paragraph","children":[{"type":"text","value":"Macrophage HAM-56 reacts with tingible macrophages (found in the germinal centers of lymph nodes), interdigitating macrophages of lymph nodes and tissue macrophages, (e.g., Kupffer cells of the liver and alveolar macrophages of the lung). This antibody also stains a subpopulation of endothelial cells, most prominently those of the capillaries and smaller blood vessels. HAM-56 reacts with monocytes, but is unreactive with B and T-lymphocytes."}]}]}