Interleukin 13
Interleukin 13 (IL-13) and its relative interleukin-4 are signalling proteins of the adaptive immune systems of vertebrates. They are immunoregulatory cytokines belonging to the type 2 cytokine family, primarily produced by activated T helper 2 (Th2) cells, as well as innate lymphoid cells type 2 (ILC2s), natural killer T cell, mast cells, basophils, eosinophils and nuocytesduring type 2 immune responses. Type 2 immune responses are essential for defense against large extracellular parasites like helminths, by promoting B-cell maturation, immunoglobulin E (IgE) class switching, eosinophil recruitment, mucus production, and alternative (M2) macrophage polarization that suppresses excessive inflammation and supports tissue repair. Interleukin-13 is a central regulator in IgE synthesis, goblet cell hyperplasia, mucus hypersecretion, airway hyperresponsiveness, fibrosis and chitinase up-regulation. It is a mediator of allergic inflammation and different diseases including asthma, and atopic dermatitis.