GM-CSF, Recombinant, Human, aa18-144 (CHO-expressed, CSF2)

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 a number of different cell types (including 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 is a survival factor for and activates the effector functions of granulocytes, monocytes/macrophages, and eosinophils (1, 2). GM­CSF promotes a Th1 biased immune response, angiogenesis, allergic inflammation, and the development of autoimmunity (3-5). It shows clinical effectiveness in ameliorating chemotherapy­induced neutropenia, and GM-CSF transfected tumor cells are utilized as cancer vaccines (6, 7). The 22kD glycosylated GM-CSF, similar to IL­3 and IL­5, is a cytokine with a core of four bundled alpha-helices (8-12). Mature human GM-CSF shares 63%-70% amino acid sequence identity with canine, feline, porcine, and rat GM-CSF and 54% with mouse GM-CSF. GM-CSF exerts its biological effects through a heterodimeric receptor complex composed of GM-CSF Ralpha/CD116 and the signal transducing common beta chain (CD131) which is also a component of the high­affinity receptors for IL-3 and IL-5 (13, 14). In addition, GM-CSF binds a naturally occurring soluble form of GM-CSF Ralpha (15). Human GM-CSF is active on canine and feline cells but not on murine cells (16-18). Source: Recombinant protein corresponding to aa18-144 from human GM-CSF, CHO-derived. Molecular Weight: ~20-35kD, Endotoxin: <0.01EU/1ug (LAL method), Storage and Stability: Lyophilized powder may be stored at -20°C. Stable for 12 months at -20°C. Reconstitute in sterile ddH2O or PBS. Aliquot to avoid repeated freezing and thawing. Store at -20°C. Reconstituted product is stable for 12 months at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.