INTERLEUKIN 21 HUMAN (C15-1717-985)

General description

IL21 (interleukin 21) is a member of the γ-chain type I cytokine family, and a four-α-helix bundle pleiotropic cytokine. This gene is localized to human chromosome 4q26–q27. Although, it is predominantly produced by T follicular helper (TFH) and T helper-17 (TH17) cells, it is also produced by CD4⁺ T cells, neutrophils and natural killer cells. Under certain conditions, it is also produced by CD8⁺ T cells. Recombinant human IL-21 is a 15.0 kDa protein consisting of 132 amino acid residues.

Biochem/physiol Actions

IL21 (interleukin 21) functions on its heterodimeric receptor IL21R, which is expressed widely on immune and non-immune cells. Therefore, IL21 exerts its effects on a wide range of cell types and has a pleiotropic role in immune response regulation. This protein activates Janus kinase (JAK)-signal transducer and activator of transcription (STAT) signaling pathway and functions through mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K)-AKT signaling pathways. Studies show that in rheumatoid arthritis fibroblast-like synoviocytes (RA-FLS), IL21 facilitates migration, invasion and production of MMPs (MMP-2, MMP-3, MMP-9, MMP-13) (matrix metalloproteinases). Therefore, it has potential as a therapeutic target in the treatment of RA. Studies show that CD3⁺TCRvβ11⁺ NK (natural killer) T cells isolated from a local Mycobacterium tuberculosis infection site produce IL21, which in turn assists B cells to produce and release IgG (immunoglobulin) and IgA, to help fight the infection.

Sequence

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

Physical form

Lyophilized from a sterile (0.2 micron) filtered aqueous solution containing 10 mM sodium phosphate, pH 7.5

Reconstitution

Centrifuge the vial prior to opening. Reconstitute in water to a concentration of 0.1-1.0 mg/ml. Do not vortex. This solution can be stored at 2-8°C for up to 1 week. For extended storage, it is recommended to further dilute in a buffer containing a carrier protein (example 0.1% BSA) and store in working aliquots at -20°C to -80°C.