Abbreviation
Recombinant Human IL-21 protein (Active)
Purity
Greater than 95% as determined by SDS-PAGE.
Endotoxin
≤10 EU/mg by the LAL method
Activity
Measured by its ability to enhance IFN-gamma secretion in NK-92 human natural killer lymphoma cells. The ED50 for this effect is ≤ 20 ng/mL.
Alternative Names
Interleukin-21; IL-21; Za11; IL21
Species
Homo sapiens (Human)
Expression Region
25-162aa
Target Protein Sequence
HKSSSQGQDRHMIRMRQLIDIVDQLKNYVNDLVPEFLPAPEDVETNCEWSAFSCFQKAQLKSANTGNNERIINVSIKKLKRKPPSTNAGRRQKHRLTCPSCDSYEKKPPKEFLERFKSLLQKMIHQHLSSRTHGSEDS
Note: The complete
sequence may include tag sequence, target protein sequence, linker sequence and extra sequence that is
translated with the protein sequence for the purpose(s) of secretion, stability, solubility, etc.
If the exact amino acid sequence of this recombinant protein is critical to your application,
please explicitly request the full and complete sequence of this protein before ordering.
Protein Length
Full Length of Mature Protein
Tag Info
Tag free
The tag type will be determined during production process. If you have specified tag type, please tell us and we will develop the specified tag preferentially.
Buffer
Lyophilized from a 0.2 μm filtered solution containing PBS, 5% mannitoland 0.01% Tween 80, pH 7.4
Storage
Store at -20°C/-81°C upon receipt, aliquoting is necessary for mutiple use. Avoid repeated freeze-thaw cycles.
Lead Time
3-7 business days
Note: All of our proteins are default shipped with normal blue ice packs, if you request to ship with dry ice, please communicate with us in advance and extra fees will be charged.
Notes
Repeated freezing and thawing is not recommended. Store working aliquots at 4°C for up to one week.
Shelf Life
The shelf life is related to many factors, storage state, storage temperature and the stability of the product itself. Generally, the shelf life of lyophilized form is 6 months at -20°C/-80°C from the date of receipt.
Datasheet & COA
Please contact us to get it.
Description
Interleukin-21 plays a central role in regulating NK cell and T cell effector functions, yet its short half-life and tendency to aggregate during production have historically limited experimental reproducibility. This tag-free recombinant human IL-21, spanning the complete mature protein sequence (aa 25–162), demonstrates robust biological activity with an ED50 ≤ 20 ng/mL in stimulating IFN-γ secretion from NK-92 cells, providing a quantitative benchmark for dose-response studies in NK cell activation assays and co-culture experiments examining cytotoxic lymphocyte function. The endotoxin level of ≤10 EU/mg satisfies the contamination thresholds typical for primary immune cell assays, where LPS artifacts can confound interpretation of cytokine-driven signaling through JAK1/JAK3 and STAT3 pathways. Purity exceeding 95% by SDS-PAGE, combined with mammalian expression that preserves native glycosylation, supports use in differentiation studies with naïve T cells, B cell proliferation assays, and as a positive control in IL-21 detection platforms.