| Description : |
Human IL-21 is encoded by IL-21 gene located on Chr. 4. It is a pleiotropic cytokine produced by CD4+ T cells in response to antigenic stimulation and can regulating immune system cells, for instance cytotoxin T cells and natural killer cells. Additionally, it can induce target cells division or proliferation. IL-21 elicits its effect through binding to IL-21R, which also contains the gamma chain found in other cytokine receptors such as IL-2, IL-4, IL-7, IL-9 and IL-15. IL-21/IL-21R interaction triggers a cascade of events which includes activation of the tyrosine kinases JAK1 and JAK3, followed by activation of the transcription factors STAT1 and STAT3. IL-21 shows having much relation with clinical illnesses, including cancer immunotherapy, viral infections and allergies. |
| Source : |
E.coli |
| Species : |
Human |
| Form : |
Lyophilized from a 0.2μm filtered concentrated solution in PBS, pH 7.4. |
| Bio-activity : |
Fully biologically active when compared to standard. The ED50 as determined by a cell proliferation assay using human N1186 T cells is less than 20 ng/ml, corresponding to a specific activity of > 5.0 × 10⁴ IU/mg. |
| Molecular Mass : |
Approximately 15.4 kDa, a single non-glycosylated polypeptide chain containing 133 amino acids. |
| Protein length : |
133 |
| AA Sequence : |
QGQDRHMIRMRQLIDIVDQLKNYVN DLVPEFLPAPEDVETNCEWSAFSCF QKAQLKSANTGNNERIINVSIKKLK RKPPSTNAGRRQKHRLTCPSCDSYE KKPPKEFLERFKSLLQKMIHQHLSS RTHGSEDS |
| Endotoxin : |
Less than 1 EU/µg of rHuIL-21 as determined by LAL method. |
| Purity : |
>97% by SDS-PAGE and HPLC analysis. |
| Storage : |
Use a manual defrost freezer and avoid repeated freeze-thaw cycles. 12 months from date of receipt, -20 to -70 centigrade as supplied. 1 month, 2 to 8 centigrade under sterile conditions after reconstitution. 3 months, -20 to -70 centigrade under sterile conditions after reconstitution. |
| 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 centigrade. Further dilutions should be made in appropriate buffered solutions. |
