Interleukin-4 (IL-4, B-cell stimulatory factor 1, Lymphocyte stimulatory factor 1, Binetrakin, Pitrakinra, B cell differentiation factor gamma, B cell growth factor, interleukin-4)

IL-4 (15 to 19 kDa) is produced by a variety of T cell thymocyte populations, as well as some mast cell precursors that are non-T or B cell types. Il-4 plays an important role in the activation of resting B-cells and in the subsequent proliferation and differentiation of B-cells. IL-4 is essential for IgE synthesis in vitro and its involvement with allergic diseases has been investigated. Il-4 has anti-inflammatory effects.