Recombinant Human IL-15 (I-196-GRP)

Interleukin-15 (IL-15), also known as IL-T and MGC9721, is an immunomodulating cytokine that stimulates the proliferation of T lymphocytes and shares many biological properties with IL-2 (1). IL-15 mRNA is expressed in many cell types and tissues including adherent peripheral blood mononuclear cells, fibroblasts, and epithelial cells, monocytes, placenta and skeletal muscle. It exerts its biological activities primarily on T cells and is essential in the development, survival and activation of NK cells (2). IL-15 is also secreted by activated monocytes/macrophages following infection by virus (3). It competes for binding sites with IL-2, as both stimulate the growth of cells through the IL-2 receptor and thus negatively regulate each other's activity (4). IL-15 induces the activation of JAK kinases, as well as the phosphorylation and activation of transcription activators STAT3, STAT5, and STAT6. It can recruit and activate T lymphocytes in the synovial membrane, thereby contributing to Rheumatoid arthritis pathogenesis (5). Increased expression of IL-15 has also been implicated with inflammatory bowl disease and diseases affiliated with retroviruses HIV and HTLV-I (6). Human IL-15 is biologically active on mouse cells as measured by the dose-dependent stimulation of the proliferation of mouse CTLL cells.