IL-21 Recombinant Protein

IL-21, Interleukin-21, IL-21

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 conjunction) with IL-4 of IgG production, and induction of apoptotic effects in na?ve 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 gamma 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 murine IL-21 is a 15.0 kDa protein consisting of 130 amino acid residues.

Assay #1: Measured by its ability to induce STAT3 signaling in U937 Stat3-Luc reporter cells.

Assay #2: Determined by its ability to stimulate the proliferation of human ANBL-6 cells. The expected ED50 is < 1.0 ng/ml, corresponding to a specific activity of > 1 x 106 units/mg

60505

interleukin 21

Il21

Mus musculus

Lyophilized

NP_068554.1

11140821

Greater than 98% by SDS-PAGE gel and HPLC analyses.

Endotoxin level is less than 0.1 ng per μg (1EU/μg).

#N/A

E. coli

Q9ES17