Recombinant Mouse Interleukin-21 protein (Il21)

Function

Cytokine with immunoregulatory activity. May promote the transition between innate and adaptive immunity. Induces the production of IgG(1) and IgG(3) in B-cells (PubMed:15100251). Implicated in the generation and maintenance of T follicular helper (Tfh) cells and the formation of germinal-centers. Together with IL6, control the early generation of Tfh cells and are critical for an effective antibody response to acute viral infection (PubMed:23045607). May play a role in proliferation and maturation of natural killer (NK) cells in synergy with IL15 (PubMed:11970879). May regulate proliferation of mature B- and T-cells in response to activating stimuli. In synergy with IL15 and IL18 stimulates interferon gamma production in T-cells and NK cells (By similarity). During T-cell mediated immune response may inhibit dendritic cells (DC) activation and maturation (PubMed:12893770)

Subcellular Location

Secreted

Tissue Specificity

Expressed in CD4(+) T cells

• Parrish-Novak J. et al. Interleukin 21 and its receptor are involved in NK cell expansion and regulation of lymphocyte function. — Nature (2000)
• Guobing C. et al. Mouse interleukin 21 can improve the anti-tumor effect of LAK cells. (OCT-)
• Kasaian M.T. et al. IL-21 limits NK cell responses and promotes antigen-specific T cell activation: a mediator of the transition from innate to adaptive immunity. — Immunity (2002)
• Brandt K. et al. Interleukin-21 inhibits dendritic cell activation and maturation. — Blood (2003)
• Pene J. et al. IL-21 is a switch factor for the production of IgG1 and IgG3 by human B cells. — J. Immunol. (2004)
• Karnowski A. et al. B and T cells collaborate in antiviral responses via IL-6, IL-21, and transcriptional activator and coactivator, Oct2 and OBF-1. — J. Exp. Med. (2012)