Recombinant Murine GM-CSF

GM-CSF was initially characterized as a factor that can support the in vitro colony formation of granulocyte-macrophage progenitors. It is also a growth factor for erythroid, megakaryocyte, and eosinophil progenitors. GM-CSF is produced by T cells, B cells, macrophages, mast cells, endothelial cells, fibroblasts, and adipocytes in response to cytokine or inflammatory stimuli. On mature hematopoietic cells, GM-CSF acts as a prosurvival factor and activates effector functions of granulocytes, monocytes/macrophages, and eosinophils. It promotes a Th1 biased immune response, angiogenesis, allergic inflammation, and the development of autoimmunity. The 22 kDa glycosylated GM-CSF, similar to IL-3 and IL-5, is a cytokine with a core of four bundled alpha-helices. Mature mouse GM-CSF shares 49% - 54% amino acid sequence identity with canine, feline, human, and porcine GM-CSF and 69% with rat GM-CSF. The activity of GM-CSF is species specific between human and mouse. Mouse GM-CSF is only weakly active on rat cells, although rat GM-CSF is fully active on mouse cells.