IL21 Gene

The IL21 gene (IL21 stands for "Interleukin-21") is a protein-coding gene located on chromosome 4q27. The gene encodes a member of the"gamma chain family" of cytokines (interleukins) with immunoregulatory activity.

The encoded protein(interleukin-21) plays a role in both innate and adaptive immune responses by inducing differentiation, proliferation, and activity of several target cells such as macrophages, natural killer cells, B cells, and cytotoxic T cells. Dysregulation of this gene plays a role in numerous immune-mediated diseases such as lupus erythematosus systemic, psoriasis and various chronic inflammatory diseases. Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene.

Diseases associated with IL21 include:

• Immunodeficiency, Common Variable, 11 (CVID11)
• and
• Dacryoadenitis.

IL-21 is a cytokine with immunoregulatory activity. It, together with IL6, regulates early generation of Tfh cells and is critical for an effective antibody response to acute viral infections. May play a role in natural killer (NK) cell proliferation and maturation in synergy with IL15. May regulate proliferation of mature B and T cells in response to activating stimuli.

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