IL-13

Alias: Interleukin-13, NC3

IL-13 is a pleiotropic TH2 cytokine expressed by activated T helper cells, CD8+ T cells, and NK cells. IL-13 functions to suppress macrophage cytotoxic activity, upregulation of IL-1RA expression, and suppression of inflammatory cytokine expression. IL-13 binds to the receptor complex IL-13R composed of IL-4Rα and IL-13Rα1, that it shares with IL-4, on various cell types that include mononuclear phagocytes and large granular lymphocytes B cells. IL-13 induces CD23 expression on B cells, promotes B cell proliferation in combination with anti-Ig or CD40 antibodies, and stimulates secretion IgE, and IgG4. IL-13 has also been shown to prolong survival of human monocytes and increases surface expression of MHC class II and members of the integrin superfamily, like CD11b, CD11c, CD18, CD29 and CD49e, and induces IFNγ production by NK cells. IL-13 also inhibits the production of a series of cytokines that include IL-1, IL-6, IL-8, and TNFα by activated human monocytes. As a biomarker, the measurement of IL-13 in body fluids may thus provide further information about the pathophysiology of atopic diseases and is known to play a central role in the pathogenesis of asthma.