<unk> , more commonly known as leukopoietin, is a category of substances produced by neutrophils when they encounter a foreign antigen. Leukopoietin stimulates the bone marrow to increase the rate of leukopoiesis in order to replace the neutrophils that will inevitably be lost when they begin to phagocytose the foreign antigens.<unk> s include colony stimulating factors (CSFs) (produced by monocytes and T lymphocytes), interleukins (produced by monocytes, macrophages, and endothelial cells), prostaglandins, and lactoferrin.
Leukocyte-promoting factor
Macrophage-activating factor
Lymphokine
Leukemia inhibitory factor
Macrophage colony-stimulating factor
Cytokine
Passenger leukocyte
Tumor antigen