IL-21 Protein (AA 30-162)

Catalog No. ABIN2666654

This Recombinant IL-21 protein is expressed in Escherichia coli (E. coli).

Quick Overview for IL-21 Protein (AA 30-162) (ABIN2666654)

Target: IL-21 (IL21) (Interleukin 21 (IL21))

Protein Type: Recombinant

Biological Activity: Active

Origin: Human

Source: Escherichia coli (E. coli)

Application: Flow Cytometry (FACS)

Purity: > 98 % , as determined by Coomassie stained SDS-PAGE.

Product Details

Protein Characteristics: AA 30-162

Sterility: 0.22 μm filtered

Endotoxin Level:

Less than 0.01 ng per μg cytokine as determined by the LAL method.

Application Details

Application Notes: Optimal working dilution should be determined by the investigator.

Comment:

Biological activity: The ED50 is 0.3-0.5 ng/ml, corresponding to a specific activity 2.0-3.3 x 106 units/mg as determined by a dose-dependent induction of IFNγ secretion by NK-92 cells.

Restrictions: For Research Use only

Handling

Format: Liquid

Reconstitution: For maximum results, quick spin vial prior to opening. The protein can be aliquoted and stored from -20 °C to -70 °C. Stock solutions can also be prepared at 50-100 μg/mL in sterile buffer (PBS, HPBS, DPBS, or EBSS) containing carrier protein such as 0.2-1 % BSA or HSA and stored in working aliquots at -20 °C to -70 °C.

Buffer: 0.22 μm filtered protein solution is in PBS.

Handling Advice: Avoid repeated freeze/thaw cycles.

Storage: -20 °C

Storage Comment: Unopened vial can be stored between 2°C and 8°C for one month, at -20°C for six months, or at -70°C for one year.

Target Details

Target: IL-21 (IL21) (Interleukin 21 (IL21))

Alternative Name: IL-21

Background: IL-21 was identified by a functional screening from conditioned medium of activated T cells using Baf3-IL-21R transfectants. In normal B cells, IL-21 can mediate cell proliferation, growth arrest, and terminal differentiation, or apoptosis, depending on their activation status. IL-21 enhances B cell proliferation following incubation with an activating CD40 antibody. This result suggests that IL-21 enhances B cell function following T:B cell interactions. Nevertheless, IL-21 inhibits the proliferation of murine and human B cells stimulated with anti-IgM antibodies. In addition, IL-21 enhances proliferation, cytotoxic activity, and IFNγ production by CD8-effector T cells, and induces terminal differentiation of activated natural killer (NK) cells. Also, IL-21 can drive Th17 responses in conjunction with TGF-β. Nevertheless, IL-21 is not essential for the differentiation of Th17 cells in vitro or in vivo, as it was showed using IL-21 and IL-21R-deficient mice. IL-6 induces the production of IL-21 from CD4 T cells upon TCR stimulation. In addition, IL-6 and IL-21 are key players in the Tfh differentiation, characterized by increased protein expression of both Bcl-6 and CXCR5. IL-21R complex is formed with the IL-21R-alpha chain and the common subunits (γc) shared with other interleukins, such as IL-2, IL-4, IL-7, IL-9, and IL-15.

Molecular Weight: The 133 amino acid recombinant protein has a predicted molecular mass of approximately 15.5 kDa. The DTT-reduced and non-reduced protein migrate at approximately 16 kDa by SDS-PAGE. The N-terminal amino acid is Glutamine.

Pathways: JAK-STAT Signaling, Regulation of Leukocyte Mediated Immunity, Positive Regulation of Immune Effector Process, Production of Molecular Mediator of Immune Response