Granulocyte macrophage colony-stimulating factor, often abbreviated to GM-CSF, is a protein secreted by macrophages that stimulates stem cells to produce granulocytes (neutrophils, eosinophils, and basophils) and macrophages. It is thus part of the immune/inflammatory cascade, whereby activation of a small number of macrophages produces more of them in circulation.
Granulocyte macrophage colony-stimulating factor is distinct from granulocyte colony-stimulating factor.
Also known as sargramostim when the protein is expressed in yeast cells (trademarked Leukine®), granulocyte macrophage colony-stimulating factor is used as a medication to stimulate the production of white blood cells, especially granulocytes and macrophages, following chemotherapy.
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Leukine.com (sargramostim) - Official pharmaceutical website offers information for patients and prescriber.
Sargramostim - Information about dosage, side effects, and other aspects of use of this medication for HIV-related conditions. Brand names include Leukine, Prokine, and GM-CSF.