INTERLEUKIN-4

Interleukin 4 (IL-4) is a glycoprotein produced by a restricted number of cells such as T lymphocytes and mast cells. IL-4 acts on numerous cell types including T and B lymphocytes, neutrophils, basophils and eosinophils, monocytes/macrophages, fibroblasts and endothelial cells. Its biological effects depend on the status of maturation and activation of a given cell, and on the cellular environment. Moreover, IL-4 can exert biological effects in an indirect fashion as it modulates cytokine production by T and B lymphocytes, macrophages and fibroblasts. IL-4 plays a major role in IgE synthesis through the induction of isotype switching in virgin B cells. This property is blocked by interferons. IL-4 binds to a single class of high affinity receptors which are expressed at low density on many cell types and composed of at least one glycoprotein of 130 kDa. IL-4 may prove useful as an antitumoral and anti-inflammatory agent.