GM-CSF is a hematopoietic factor that is produced by T cells, macrophages, fibroblasts and endothelial cells. This multifunctional cytokine stimulates progenitor cells of neutrophils, eosinophils and macrophages. GM-CSF is also a differentiation and activating factor for granulocytic and monocytic cells. The MP1-31G6 antibody reacts with mouse granulocyte/macrophage-colony stimulating factor (GM-CSF). The MP1-31G6 antibody can neutralize the bioactivity of natural or recombinant GM-CSF.