SDF-1α and β are stromal-derived, CXC chemokines that signal through the CXCR4 receptor. SDF-1α and β chemoattract B and T cells, and have been shown to induce migration of CD34+ stem cells. Additionally, the SDF-1 proteins exert HIV-suppressive activity in cells expressing the CXCR4 receptor. Human and murine SDF-1 proteins act across species. SDF-1α and β contain the four highly conserved cysteine residues present in CXC chemokines. The mature SDF-1β protein, produced by an N-terminal truncation of two additional amino acids, after removal of the signal sequence, contains 72 amino acid residues. Recombinant Human SDF-1β is an 8.5 kDa protein containing 72 amino acid residues.
Amino Acid Sequence
Determined by its ability to chemoattract human peripheral T cells activated with PHA and IL-2 using a concentration range of 20–80 ng/ml.
Endotoxin level is <0.1 ng/μg of protein (<1EU/μg).
Centrifuge the vial prior to opening. Reconstitute in water to a concentration of 0.1–1.0 mg/ml. Do not vortex. This solution can be stored at 2–8°C for up to 1 week. For extended storage, it is recommended to further dilute in a buffer containing a carrier protein (example 0.1% BSA) and store in working aliquots at –20°C to –80°C.