Description: Human GM-CSF (Granulocyte/Monocyte-Colony Stimulating Factor) is a differentially glycosylated factor produced mainly by activated T cells and macrophages. Endothelial cells and fibroblasts can also produce GM-CSF after exposure to TNF alpha, IL-1, IL-2 and IFN gamma. GM-CSF is found associated with extracellular matrix and in membrane-bound formats too. GM-CSF stimulates proliferation, activation and differentiation of macrophages and granulocytes and their progenitors.