名稱：重組人SDF-1β/CXCL12β

Synonyms：hSDF-1 beta, IRH, hIRH, PBSF

Species：9

Accession：P48061

GeneID：6387

Source：Escherichia coli.

Molecular Weight：Approximately 8.5 kDa, a single non-glycosylated polypeptide chain containing 72 amino acid residues.

Quantity：2μg/10μg/1000μg

AA Sequence：KPVSLSYRCP CRFFESHVAR ANVKHLKILN TPNCALQIVA RLKNNNRQVC IDPKLKWIQE YLEKALNKRF KM

Purity：> 97 % by SDS-PAGE and HPLC analyses.

Biological Activity：Fully biologically active when compared to standard. The biological activity determined by a chemotaxis bioassay using PHA and rHuIL-2 activated human peripheral blood T-lymphocytes is in a concentration range of 20-80 ng/ml.

Physical Appearance：Sterile Filtered White lyophilized (freeze-dried) powder.

Formulation：Lyophilized from a 0.2 μm filtered concentrated solution in PBS, pH 7.4.

Endotoxin：Less than 1 EU/μg of rHuSDF-1β/CXCL12β as determined by LAL method.

Reconstitution：We recommend that this vial be briefly centrifuged prior to opening to bring the contents to the bottom. Reconstitute in sterile distilled water or aqueous buffer containing 0.1 % BSA to a concentration of 0.1-1.0 mg/mL. Stock solutions should be apportioned into working aliquots and stored at ≤ -20 °C. Further dilutions should be made in appropriate buffered solutions.

Stability & Storage：Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
- 12 months from date of receipt, -20 to -70 °C as supplied.
- 1 month, 2 to 8 °C under sterile conditions after reconstitution.
- 3 months, -20 to -70 °C under sterile conditions after reconstitution.

Reference：1. Shirozu M, Nakano T, Inazawa J, et al. 1995. Genomics. 28:495-500.
2. Yu L, Cecil J, Peng SB, et al. 2006. Gene. 374:174-9.
3. De La Luz Sierra M, Yang F, Narazaki M, et al. 2004. Blood. 103:2452-9.
4. Charnaux N, Brule S, Hamon M, et al. 2005. FEBS J. 272:1937-51.
5. Bleul CC, Fuhlbrigge RC, Casasnovas JM, et al. 1996. J Exp Med. 184:1101-9.
6. Ara T, Nakamura Y, Egawa T, et al. 2003. Proc Natl Acad Sci U S A. 100:5319-23.
7. Askari AT, Unzek S, Popovic ZB, et al. 2003. Lancet. 362:697-703.
8. Ma Q, Jones D, Borghesani PR, et al. 1998. Proc Natl Acad Sci U S A. 95:9448-53.
9. Kryczek I, Wei S, Keller E, et al. 2007. Am J Physiol Cell Physiol. 292:C987-95.

Background：CXCL12 also known as SDF-1 is belonging to the CXC chemokine family. It is encoded by the CXCL12 gene. In recently study, Human CXCL12 is expressed as six isoforms that differ only in the C-terminal tail. And all SDF-1 isoforms undergo proteolytic processing of the first two N-terminal amino acids. In all SDF-1 isoforms, SDF-1β is the canonical sequence. It has the complete amino acids in the C-terminal tail. On the cell surface, the receptor for this chemokine is CXCR4 and syndecan4. CXCL12 is strongly chemotactic for T-lymphocytes, monocytes, but not neutrophils. CXCL12 is a very important factor in carcinogenesis and the neovascularisation linked to tumor progression.

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