背景介绍 SDF-1alpha and SDF-1beta are small cytokines belonging to the CXC- Chemokines. SDF-1 is identical with a chemokine reported to function as a pre-B-cell growth factor in the presence of IL-7 and isolated originally from a murine bone marrow stromal cell line. Human SDF-1alpha and SDF-1beta are encoded by a single gene and arise by alternative splicing. SDF-1 acts on lymphocytes and monocytes but not neutrophils in vitro and is a highly potent chemoattractant for mononuclear cells in vivo. In addition, SDF-1 also induces intracellular actin polymerization in lymphocytes. SDF acts as a chemoattractant for human hematopoietic progenitor cells expressing CD34 giving rise to mixed types of progenitors, and more primitive types. The chemotactic response is inhibited by pertussis toxin. Chemotaxis of CD34(+) cells in response to SDF is increased by IL-3 in vitro. SDF has been shown also to induce a transient elevation of cytoplasmic calcium in these cells. 产品介绍 Recombinant SDF-1 alpha is a disulfide-linked monomer protein consisting of 69 amino acid residues, migrates as an approximately 8 kDa protein under non-reducing and reducing conditions in SDS-PAGE. Optimized DNA sequence encoding human Stromal Cell-Derived Factor-1 alpha was expressed in E. coli.