Hu Recom GM-CSF (E.coli Exp), 20 µg

Supplied by STEMCELL Technologies as a lyophilized laboratory reagent, the product is recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF; also known as colony-stimulating factor 2, CSF-2, MGI-1GM, or Pluripoitin-alpha) expressed in E. coli with a reported purity of ≥ 95%, prepared as a lyophilized powder from a sterile-filtered aqueous solution containing sodium phosphate at pH 7.5 (S2, S3).

GM-CSF promotes the proliferation and differentiation of hematopoietic progenitor cells and supports the generation of neutrophils, eosinophils, and macrophages. In synergy with cytokines such as stem cell factor, IL-3, erythropoietin, and thrombopoietin, it also stimulates erythroid and megakaryocyte progenitors. GM-CSF is produced by multiple cell types, including stromal cells, Paneth cells, macrophages, dendritic cells, endothelial cells, smooth muscle cells, fibroblasts, chondrocytes, and Th1 and Th17 T cells. The GM-CSF receptor is composed of the cytokine-specific α subunit (GMRα; CD116) and the common βc subunit (CD131) shared with IL-3 and IL-5 receptors (S2).

The protein has a predicted molecular mass of 14.6 kDa (UniProt accession P04141) and is reported as not active on mouse cells. Specific activity is approximately 1.6 x 10^4 IU/µg when calibrated against the human recombinant GM-CSF WHO International Standard (NIBSC code 88/646), and ≥ 5 x 10^6 units/mg, with an EC50 ≤ 200 pg/mL by a TF-1 cell proliferation assay. Endotoxin is ≤ 1 EU/µg protein by kinetic LAL analysis. According to the safety data sheet, the material is a solid that is not classified as hazardous under the Globally Harmonized System. For use, centrifuge the vial before opening and reconstitute in sterile water to at least 0.1 mg/mL by pipetting down the sides of the vial without vortexing; bovine serum albumin may be added to 0.1% for longer storage. Store at -20°C to -80°C; stable as supplied for 12 months from date of receipt (S1, S2, S3).