Synonyms:
IL-21, CVID11, Za11
Description:
Interleukin 21 (IL-21) is a member of the common-gamma chain family of cytokines with
immunoregulatory activity. IL-21 plays a role in both the innate and adaptive immune
responses by inducing the differentiation, proliferation and activity of multiple target cells
including macrophages, natural killer (NK) cells, B cells and cytotoxic T cells. IL-21 is
produced by CD4+ T cells in response to antigenic stimulation. Its action generally
enhances antigen-specific responses of immune 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. The IL-21R activates the JAK/STAT
signaling pathway and is expressed on T, B, and NK cells. Within the B cell lineage, IL-21
is a switch factor regulating IgG1 and IgG3 antibody production. IL-21 also cooperates
with IL-4 for the production of multiple antibody classes in B cells.
Uniprot Name:
Interleukin-21
Molecular Weight:
15.4 kDa (132 aa)
Physical State:
Lyophilized
Formulation:
Lyophilized from sterile-filtered 10 mM sodium phosphate, pH 7.5.
Purity:
>95% by reducing and non-reducing SDS-PAGE
Biological Activity:
ED50 < 50 ng/ml, determined by dose-dependent proliferation of B9 cells.
ED50 < 2.0 ng/ml, determined by dose-dependent proliferation of ANBL-6 cells.
Specific Activity:
> 2.0 × 104 U/mg, determined by dose-dependent proliferation of B9 cells.
> 5.0 × 105 U/mg, determined by dose-dependent proliferation of ANBL-6 cells.
Endotoxin Level:
≤1 EU/µg of protein by kinetic LAL analysis
Amino Acid Sequence:
MQDRHMIRMR QLIDIVDQLK NYVNDLVPEF LPAPEDVETN CEWSAFSCFQ KAQLKSANTG NNERIINVSI KKLKRKPPST NAGRRQKHRL TCPSCDSYEK KPPKEFLERF KSLLQKMIHQ HLSSRTHGSE DS
Reconstitution:
Centrifuge vial prior to opening. Add sterile distilled water to a concentration of 0.1 mg/ml. DO NOT VORTEX. Allow several minutes for complete reconstitution. Further dilutions should be made in appropriate buffered solutions.
Storage/Stability:
Lyophilized product is stable at room temperature for shipping purposes. Upon receipt, store at -20°C to -80°C for up to 1 year. Upon reconstitution, the preparation is stable for up to 1 month at 2-8°C. For long term storage, freeze in working aliquots and store at -20 to -80°C. For maximal stability, dilute to working aliquots in a 0.1% BSA solution. Avoid repeated freeze-thaw cycles.