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Due to a water main break, our U.S. warehouse is closed for the remainder of the day, Thursday, July 28. Orders placed today will ship tomorrow, Friday, July 29. We apologize for the inconvenience.

To Purchase # 8920SC

8920SC 10 µg (With Carrier) $199.00
8920SF 10 µg (Carrier Free) $199.00
8920LC 50 µg (With Carrier) $599.00
8920LF 50 µg (Carrier Free) $599.00


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Source / Purification

Recombinant human IL-21 (hIL-21) Gln30-Ser155 (Accession # NM_021803) was expressed in human 293 cells at Cell Signaling Technology.

Product Description


>98% as determined by SDS-PAGE of 6 μg reduced (+) and non-reduced (-) recombinant hIL-21. Less than 9% is nicked after Arg114 to generate 6 kDa and 10 kDa polypeptides observed in reduced (+) hIL-21.

Molecular Formula:

Recombinant hIL-21 contains no "tags" and the nonglycosylated protein has a calculated MW of 15,463. DTT-reduced and non-reduced protein migrate as 16 kDa polypeptides, with non-reduced having slightly greater mobility due to intramolecular cystines. The expected amino-terminal QGQDR of recombinant hIL-21 was verified by amino acid sequencing.


The bioactivity of recombinant hIL-21 was determined by its ability to induce IFN-γ production by NK-92 cells. The ED50 of each lot is between 1.0-6.0 ng/ml.


Less than 0.01 ng endotoxin/1 μg hIL-21.

Product Usage Information


With carrier: Lyophilized from a 0.22 μm filtered solution of PBS, pH 7.2 containing 20 μg BSA per 1 μg hIL-21. Carrier free: Lyophilized from a 0.22 μm filtered solution of PBS, pH 7.2.

Storage: Stable in lyophilized state at 4°C for 1 year after receipt. Sterile stock solutions reconstituted with carrier protein are stable at 4°C for 2 months and at -20°C for 6 months. Avoid repeated freeze-thaw cycles.Maintain sterility. Storage at -20°C should be in a manual defrost freezer.

IL-21 is produced by Th17, T follicular helper (Tfh) and NKT cells (1-3). Targets include T cells, B cells, NK cells and dendritic cells (1-3,5). IL-21 induces proliferation and activation of NK cells, thereby up-regulating IFN-γ production and cytotoxic activity (1,3,4). IL-21 increases proliferation and survival of CD40 primed B cells (1,2) and appears to have a significant role in plasma cell differentiation (2). IL-21 binds to a complex consisting of IL-21Rα and the common γ chain, γc. IL-21 binding activates the Jak1/Jak3, Stat1, Stat3 and Stat5 pathway. IL-21 binding can also activate the MAP kinase and PI3K/Akt pathways.

1.  Parrish-Novak, J. et al. (2000) Nature 408, 57-63.

2.  Konforte, D. et al. (2009) J Immunol 182, 1781-7.

3.  Parrish-Novak, J. et al. (2002) J Leukoc Biol 72, 856-63.

4.  Strengell, M. et al. (2002) J Immunol 169, 3600-5.

5.  Davis, I.D. et al. (2007) Clin Cancer Res 13, 6926-32.

Entrez-Gene Id 59067
Swiss-Prot Acc. Q9HBE4

For Research Use Only. Not For Use In Diagnostic Procedures.
Cell Signaling Technology is a trademark of Cell Signaling Technology, Inc.

Human Interleukin-21 (hIL-21)