一.產品名稱：Recombinant Human IL-21/Peprotech  IL-21

二.Catalog Number:AF-200-21

三.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 conjunction) 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 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 15.0 kDa protein consisting of 132 amino acid residues. Manufactured using all non-animal reagents.

四.Synonyms:none

五.AA Sequence:

MQDRHMIRMR QLIDIVDQLK NYVNDLVPEF LPAPEDVETN CEWSAFSCFQ KAQLKSANTG NNERIINVSI KKLKRKPPST NAGRRQKHRL TCPSCDSYEK KPPKEFLERF KSLLQKMIHQ HLSSRTHGSE DS

六.Source:E.coli

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

八.Biological Activity:

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 approximay five cell divisions.

Avery, D.T. et. al. (2008) J. Immunol. 181, 1767-1779.

九.Cross Reactivity:Human, Mouse