Discription：SF-20 or IL-25 belongs to the IL-17 family and is also named IL-17E. It is encoded by IL-25 （IL-17E） gene located on chromosome 14 in murine and secreted by several tissues at low levels. This cytokine is initially identified as a product of bone marrow-derived stromal cells and plays an important role in proliferation of lymphoid cells and is considered as an interleukin. It rests CD8+ and CD19+ cells and activated CD8+ T cells and has been shown to bind to the surface of cells expressing the receptor TSA-1 （Thymic shared Ag-1） . Additionally, it induces the production of other cytokines, including IL-4, IL-5 and IL-13 in multiple tissues, which stimulate the expansion of eosinophils. Recombinant Murine SF-20/IL-25 is a 15.8kDa protein containing 143 amino acid.
