|Description||IL-21 is a pleiotropic cytokine produced by CD4+ T cells in response to antigenic stimulation. Its action generally enhances antigen-specific responses of immune cells. The biological effects of IL-21 include induction of differentiation of T-cells-stimulated B-cells into plasma cells and memory B-cells, stimulation (in conjuction) with IL-4 of IgG production, and induction of apoptotic effects in naïve B-cells and stimulated B-cells in the absence of T-cell signaling. Additionally, IL-21 promotes the anti-tumor activity of CD8+ T-cells and NK cells. IL-21 exerts its effect through binding to a specific type I cytokine receptor, IL-21R, which also contains the γ chain (γc) found in other cytokine receptors including IL-2, IL-4, IL-7, IL-9 and IL-15. The 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. Recombinant human IL-21 is a 15.4 kDa protein consisting of 132 amino acid residues.|
|BiologicalActivity||Assay #1:Determined by its ability to proliferate activated B cells. |
Assay #2:Determined by its ability to induce human CD40L-activated naïve B cells to undergo Ig isotype switching to IgG, using an IL-21 concentration of 50 ng/ml. Maximal activity was achieved after approximately five cell divisions.
Avery, D.T. et. al. (2008) J. Immunol. 181, 1767-1779.
|Authenticity||Verified by N-terminal and Mass Spectrometry analyses (when applicable).|
|Endotoxin||Endotoxin level is <0.1 ng/ µg of protein (<1EU/ µg).|
|Protein Content||Verified by UV Spectroscopy and/or SDS-PAGE gel.|
|Precautions||Animal-Free Recombinant Human IL-21 is for research use only and not for use in diagnostic or therapeutic procedures.|
Thousands of laboratories across the world have published research that depended on the performance of antibodies from Abgent to advance their research. Check out links to articles that cite our products in major peer-reviewed journals, organized by research category.
email@example.com, and receive a free "I Love Antibodies" mug.
Provided below are standard protocols that you may find useful for product applications.
If you have used an Abgent product and would like to share how it has performed, please click on the "Submit Review" button and provide the requested information. Our staff will examine and post your review and contact you if needed.
If you have any additional inquiries please email technical services at firstname.lastname@example.org.