Stromal Cell Derived Factor 1 beta, Recombinant, Human (SDF1b, CXCL12b, Pre-B Cell Growth-stimulating Factor, PBSF, hIRH, Chemokine (C-X-C Motif) Ligand 12b, TPAR1, SCYB12, TLSF-b)
|Growth Factors, Cytokines||Storage: -20°CShipping: RT|
Recombinant Human SDF-1b is a non-glycosylated, Polypeptide chain containing 72 amino acids and having a molecular mass of 8508 Dalton.
SDF-1 (stromal cell-derived factor-1) is small cytokine belonging to the chemokine family that is officially designated Chemokine (C-X-C motif) ligand 12 (CXCL12). Stromal cell-derived factors 1-alpha and 1-beta are small cytokines that belong to the intercrine family, members of which activate leukocytes and are often induced by proinflammatory stimuli such as lipopolysaccharide, TNF, or IL1. The intercrines are characterized by the presence of 4 conserved cysteines which form 2 disulfide bonds. They can be classified into 2 subfamilies. In the CC subfamily, which includes beta chemokine, the cysteine residues are adjacent to each other. In the CXC subfamily, which includes alpha chemokine, they are separated by an intervening amino acid. The SDF1 proteins belong to the latter group. SDF-1 is produced in two forms, SDF-1a/CXCL12a and SDF-1b/CXCL12b, by alternate splicing of the same gene. Chemokines are characterized by the presence of four conserved cysteines, which form two disulfide bonds. The CXCL12 proteins belong to the group of CXC chemokines, whose initial pair of cysteines are separated by one intervening amino acid.
CXCL12 is strongly chemotactic for lymphocytes. During embryogenesis it directs the migration of hematopoietic cells from foetal liver to bone marrow and the formation of large blood vessels. Mice which were knocked-out for CXCL12 gene were lethal before the birth or within just 1 hour of life. In adulthood CXCL12 plays an important role in angiogenesis by recruiting endothelial progenitor cells (EPC) from the bone morrow through a CXCR4 dependent mechanism. It is this function of CXCL12 that makes it a very important factor in carcinogenesis and the neovascularisation linked to tumor progression.  CXCL12 was shown to be expressed in many tissues in mice (including brain, thymus, heart, lung, liver, kidney, spleen and bone marrow).
The receptor for this chemokine is CXCR4, which was previously called fusin. This CXCL12-CXCR4 interaction used to be considered exclusive (unlike for other chemokines and their receptors), but recently it was suggested that CXCL12 is also bound by CXCR7 receptor. The gene for CXCL12 is located on human chromosome 10. In human and mouse both CXCL12 and CXCR4 show high identity of sequence: 99% and 90%, respectively.
The sequence of the first five N-terminal amino acids was determined and was found to be Lys-Pro-Val-Ser-Leu.
Dimers and Aggregates:
1% as determined by silver-stained SDS-PAGE gel analysis.
SDF-1b is fully biologically active when compared to standard. The specific activity as determined by its ability to chemoattract human peripheral T cells activated with PHA and IL-2 using a concentation of 20-80ng/ml.
0.1ng/ug (IEU/ug) of Recombinant Human Stromal Cell-Derived Factor-1 beta.
SDF-1b protein quantitation was carried out by two independent methods:
1. UV spectroscopy at 280nm using the absorbency value of 1.06 as the extinction coefficient for a 0.1% (1mg/ml) solution. This value is calculated by the PC GENE computer analysis program of protein sequences (IntelliGenetics).
2. Analysis by RP-HPLC, using a calibrated solution of Recombinant Human Stromal Cell-Derived Factor-1 beta as a Reference Standard.
Reconstitute the lyophilized SDF-1beta in sterile 18MO-cm H2O not less than 100µg/ml, which can then be further diluted to other aqueous solutions.
Storage and Stability:
Lyophilized powder may be stored at 4°C for short-term only. Reconstitute to nominal volume by adding sterile dH2O and store at -20°C. Reconstituted product is stable for 12 months at -20°C. For maximum recovery of product, centrifuge the original vial prior to removing the cap. Further dilutions can be made in assay buffer.
Source: E. coli
Purity: 98% by RP-HPLC, FPLC, or reducing/non-reducing SDS-PAGE Silver Stain. Chromatographically purified.
Form: Supplied as a lyophilized powder. No additives.
Important Note: This product as supplied is intended for research use only, not for use in human, therapeutic or diagnostic applications without the expressed written authorization of United States Biological.
1. "Entrez Gene: CXCL12 chemokine (C-X-C motif) ligand 12 (stromal cell-derived factor 1)".
2. De La Luz Sierra et al. Differential processing of stromal-derived factor-1alpha and beta explains functional diversity. Blood 103:2452-2459, 2004.
3. Bleul et al. A highly efficacious lymphocyte chemoattractant, stromal cell-derived factor 1 (SDF-1). J. Exp. Med. 184: 1101-1109, 1996.
4. Ara et al. Impaired colonization of the gonads by primordial germ cells in mice lacking a chemokine, stromal cell-derived factor-1 (SDF-1). Proc. Nat. Acad. Sci. 100: 5319-5323, 2003.
5. Askari et al. Effect of stromal-cell-derived factor 1 on stem-cell homing and tissue regeneration in ischaemic cardiomyopathy. Lancet 362: 697-703, 2003.
6. Ma et al. Impaired B-lymphopoiesis, myelopoiesis, and derailed cerebellar neuron migration in CXCR4- and SDF-1-deficient mice. Proc. Nat. Acad. Sci. 95: 9448-9453, 1998.
7. Zheng H, Fu G, Dai T, Huang H. Migration of endothelial progenitor cells mediated by stromal cell-derived factor-1alpha/CXCR4 via PI3K/Akt/eNOS signal transduction pathway.J Cardiovasc Pharmacol. 2007 Sep;50(3):274-80.Click here to read
8. Kryczek I, Wei S, Keller E, Liu R, Zou W. Stroma-derived factor (SDF-1/CXCL12) and human tumor pathogenesis. Am J Physiol Cell Physiol. 2007 Mar;292(3):C987-95.
9. Bleul et al. The lymphocyte chemoattractant SDF-1 is a ligand for LESTR/fusin and blocks HIV-1 entry. Nature 382: 829-833, 1996.
10. Balabanian et al. The chemokine SDF-1/CXCl12 binds to and signals through the orphan receptor RDC1 in T lymphocytes. J Biol Chem 280:35760-35766, 2005.
11. Burns et al. A novel chemokine receptor for SDF-1 and I-TAC involved in cell survival, cell adhesion, and tumor development. J Exp Med. 203:2201-2213, 2006.
12. Deloukas et al. The DNA sequence and comparative analysis of human chromosome 10. Nature 429:375-381, 2004.
1. Hepatocyte growth factor plays roles in the induction and autocrine maintenance of bone marrow stromal cell IL-11, SDF-1 alpha, and stem cell factor. Matsuda-Hashii Y, Takai K, Fujisaki H, Matsumoto K, Exp Hematol 2004 Oct;32(10):955-61 2. Heparan sulfate/heparin oligosaccharides protect stromal cell-derived factor-1 (SDF-1)/CXCL12 against proteolysis induced by CD26/dipeptidyl peptidase IV. Sadir R, Imberty A, Lortat-Jacob H, J Biol Chem 2004 Oct 15;279(42):43854-60 3. SDF-1 involvement in endothelial phenotype and ischemia-induced recruitment of bone marrow progenitor cells. De Falco E, Porcelli D, Straino S, Biglioli P, Blood 2004 Dec 1;104(12):3472-82 4. Primordial germ cell migration in the chick and mouse embryo: the role of the chemokine SDF-1/CXCL12. Stebler J, Spieler D, Molyneaux KA, Wylie C, Dev Biol 2004 Aug 15;272(2):351-61 5. Progenitor cell trafficking is regulated by hypoxic gradients through HIF-1 induction of SDF-1. Ceradini DJ, Kulkarni AR, Tepper OM, Galiano RD, Nat Med 2004 Aug;10(8):858-64 6. Inhibition of HIV-1 replication by GB virus C infection through increases in RANTES, MIP-1alpha, MIP-1beta, and SDF-1. Xiang J, George SL, Chang Q, Lancet 2004 Jun 19;363(9426):2040-6.