Product Information：

Formulation：

Lyophilized from 0.22 μm filtered solution in PBS，5%mannital，0.01% Tween80 pH7.4. 

Quality Control：

Purity: ≥ 95% as determined by reducing SDS-PAGE.    

Endotoxin: ＜ 0.5 EU/mg  as determined by LAL test.

Storage：

Use a manual defrost freezer and avoid repeated freeze - thaw cycles.
12 months from date of receipt, -20 to -70℃ as supplied.
1 month, 2 to 8℃ under sterile conditions after reconstitution.
6 months, -20 to -70℃ under sterile conditions after reconstitution.

FOR RESEARCH USE ONLY

Description：

This protein is a member of the common-gamma chain family of cytokines with immunoregulatory activity. The encoded protein 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 cells, B cells and cytotoxic T cells. Dysregulation of this gene plays a role in multiple immune-mediated diseases including lupus, psoriasis and chronic inflammatory diseases. Alternatively, spliced transcript variants encoding multiple isoforms have been observed for this gene. [provided by RefSeq, Dec 2011]

Interleukin (IL) -21 is a member of the common gamma chain (γc) family of cytokines and is expressed by multiple immune cell types, with activated CD4+ T cells, including T follicular helper (TFH) cells and natural killer (NK) T cells, being the major sources of this cytokine. The biological functions of IL-21 are mediated by binding to its corresponding receptor, IL-21R. IL-21R is expressed by a wide range of immune cells, including T and B cells, NK cells, DCs and macrophages as well as non-immune cells, including epithelial cells and keratinocytes. The IL-21/IL-21R signaling activates the JAK1/3-STAT, ,MAPK and PI3K signaling pathway. IL-21 has been proven to play an important role in the immune system, for example, by promoting proliferation and the development of TFH and Th17 cells, balancing helper T cell subsets, inducing B cell generation and differentiation into plasma cells, and enhancing the production of immunoglobulin. IL-21 levels are increased in the peripheral blood and tissues of patients with systematic lupus erythematosus, rheumatoid arthritis, type 1 diabetes, immune thrombocytopenia, primary Sjogren’s syndrome, autoimmune thyroid disease and psoriasis.

Figure. Signal transduction of IL-21

References：

[1] Solaymani-Mohammadi S, et al. 2019. Front Cell Infect Microbiol. 9:401.

[2] Long D, et al. 2019. J Autoimmun. 99:1-14.