GM-CSF

GM-CSF is a hematopoietic growth factor that acts on myeloid progenitor cells to promote their proliferation and differentiation into granulocytes (neutrophils, eosinophils, basophils) and monocytes/macrophages. It signals through the GM-CSF receptor, activating JAK2-STAT5 pathway, leading to increased production and functional activation of these cells, including enhanced phagocytosis, antigen presentation, and respiratory burst activity in mature cells.

Clinically, recombinant GM-CSF (sargramostim) is used to treat neutropenia following chemotherapy, myelodysplastic syndrome, or after bone marrow transplantation to accelerate myeloid recovery and reduce infection risk. It is also used to mobilize hematopoietic stem cells into peripheral blood prior to stem cell collection for transplantation.

GM-CSF plays a role in several disease states: it is implicated in the pathogenesis of autoimmune diseases (e.g., rheumatoid arthritis, multiple sclerosis) due to its pro-inflammatory effects on myeloid cells, and it is used as an adjuvant in some cancer immunotherapies (e.g., sipuleucel-T for prostate cancer, talimogene laherparepvec/T-VEC for melanoma) to enhance antigen presentation and immune response against tumors.

Autoantibodies against GM-CSF or mutations affecting its receptor are implicated in pulmonary alveolar proteinosis, a disease characterized by accumulation of surfactant-derived lipoproteins in alveoli due to impaired macrophage clearance function, since GM-CSF is critical for alveolar macrophage maturation and function.

Key boards association: GM-CSF vs G-CSF - G-CSF (filgrastim) is more lineage-specific for neutrophils, while GM-CSF has broader effects on both granulocyte and monocyte lineages, and also affects eosinophils and dendritic cells.