IL-15
IL-15 (interleukin 15) is a cytokine that regulates the activation and proliferation of T cells and natural killer cells, shaping both innate and adaptive immune responses. It is encoded by the IL15 gene, also known as MGC9721, and belongs to the IL-15/IL-21 family. Browse Assay Genie's current range of IL-15 research reagents below, or read on for the biology behind the target.
IL-15 plays a major role in the development of inflammatory and protective immune responses to microbial invaders and parasites, acting on immune cells of both the innate and adaptive systems. It stimulates the proliferation of natural killer cells, T cells and B cells and promotes the secretion of several cytokines. In monocytes it induces production of IL-8 and monocyte chemotactic protein 1 (CCL2), two chemokines that attract neutrophils and monocytes respectively to sites of infection.
Unlike most cytokines, which are released in soluble form, IL-15 is expressed in association with its high-affinity receptor IL-15RA on the surface of IL-15-producing cells. It then delivers signals to target cells that express the IL-2RB and IL-2RG receptor subunits. Receptor binding triggers phosphorylation of JAK1 and JAK3, followed by recruitment and phosphorylation of STAT3 and STAT5. In mast cells, IL-15 also induces rapid tyrosine phosphorylation of STAT6, which controls mast cell survival and the release of cytokines such as IL-4. Studies of the mouse counterpart suggest IL-15 may raise expression of the apoptosis inhibitor BCL2L1 (BCL-x(L)), possibly through STAT6, and so prevent apoptosis.
IL-15 and IL-2 share many biological activities. They bind common haematopoietin receptor subunits and may compete for the same receptor, thereby negatively regulating each other. The number of CD8+ memory cells is controlled by the balance between the two cytokines. The IL-15 protein is found in the secreted form as well as in the cytoplasm and nucleus, and alternatively spliced transcript variants of the IL-15 gene have been reported. Orthologous genes are present in mouse and rat (both Il15).
IL-15 regulates the activation and proliferation of natural killer cells and T cells, making it central to studies of lymphocyte expansion.
The balance between IL-15 and IL-2 controls the number of CD8+ memory cells, a focus for immune memory research.
IL-15 receptor binding triggers JAK1 and JAK3 phosphorylation and activates STAT3, STAT5 and STAT6, providing a model for cytokine signal transduction.
IL-15 drives protective responses to microbes and parasites and induces IL-8 and CCL2 in monocytes, linking it to inflammatory recruitment.
IL-15 is a cytokine that stimulates the proliferation of natural killer cells, T cells and B cells and promotes cytokine secretion. It signals through IL-2RB and IL-2RG subunits, triggering JAK1 and JAK3 phosphorylation and activating STAT3 and STAT5, supporting inflammatory and protective immune responses.
The gene symbol is IL15, with the full name interleukin 15 and the alias MGC9721. UniProt names the protein Interleukin-15 and places it in the IL-15/IL-21 family. NCBI Gene reports that alternatively spliced transcript variants of the gene exist.
IL-15 and IL-2 share many activities and bind common receptor subunits, so they may compete and negatively regulate each other. Together they balance CD8+ memory cell numbers. Mouse and rat both carry an Il15 ortholog; check the datasheet of any product for its validated reactivity.
Other interleukins, including IL-2 and IL-21, and related cytokines in immune signalling with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P40933; product specifications from Assay Genie datasheets.