Granulocyte-macrophage colony-stimulating factor (GM-CSF) (GM-CSF)

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a monomeric glycoprotein cytokine secreted by various cells including macrophages, T cells, mast cells, natural killer cells, endothelial cells, and fibroblasts. It stimulates hematopoietic stem cells to produce granulocytes—such as neutrophils, eosinophils—and monocytes that mature into macrophages and dendritic cells. This makes it crucial for both innate immunity and inflammatory responses. Unlike more lineage-restricted factors such as G-CSF—which primarily affects neutrophil production—GM-CSF has broader effects on multiple myeloid lineages. The biological activity of GM-CSF is mediated through binding to its specific cell surface receptor—a heterodimer composed of an alpha chain conferring ligand specificity and a beta chain shared with IL‑3/IL‑5 receptors responsible for signal transduction via JAK2/STAT5-, PI3K-, MAPK-, ERK-dependent pathways. These cascades regulate survival, proliferation, differentiation, activation state changes in target immune/myeloid populations. Clinically recombinant forms such as sargramostim are used therapeutically to treat chemotherapy-induced neutropenia/failure or mobilize peripheral blood stem cells before transplantation. Conversely—inhibitors targeting this pathway are being explored for treatment-resistant autoimmune diseases where excessive myeloid-driven inflammation plays a pathogenic role. The term “granulocyte-macrophage colony-stimulating factor induction” does not refer directly to any single protein/receptor but rather describes processes that increase expression/secretion/activity levels of this cytokine; thus it should be replaced with either “granulocyte-macrophage colony-stimulating factor” or “granulocyte-macrophage colony-stimulating factor receptor” when referring specifically to drug targets.[1][2][4][5]

Other names

Colony-stimulating factor 2CSF2

For agonists like sargramostim/molgramostim: - Bind to and activate the GM-CSF receptor, stimulating proliferation/differentiation of granulocytes and macrophages. For antagonists/mimetics under investigation: - Block binding of endogenous GM-CSF to its receptor, inhibiting downstream inflammatory signaling pathways implicated in autoimmunity/inflammation