Interleukin-15 (IL15) (Active), human, recombinant

Organism: Homo sapiens (Human). Source: E.coli. Expression Region: 49-162aa. Protein Length: Full Length of Mature Protein. Tag Info: Tag-Free. Target Protein Sequence: NWVNVISDLK KIEDLIQSMH IDATLYTESD VHPSCKVTAM KCFLLELQVI SLESGDASIH DTVENLIILA NNSLSSNGNV TESGCKECEE LEEKNIKEFL QSFVHIVQMF INTS. Purity: Greater than 95% as determined by SDS-PAGE. Endotoxin: Less than 1.0 EU/µg as determined by LAL method. Biological Activity: The ED50 as determined in a cell proliferation assay using CTLL-2 mouse cytotoxic T cells is 40-200pg/ml. Form: Lyophilized powder. Buffer: Lyophilized from a 0.2 µm filtered 20 mM PB, 150 mM NaCl, pH 7.0. Reconstitution: We recommend that this vial be briefly centrifuged prior to opening to bring the contents to the bottom. Please reconstitute protein in deionized sterile water to a concentration of 0.1-1.0 mg/mL.We recommend to add 5-50% of glycerol (final concentration) and aliquot for long-term storage at -20 °C/-80 °C. Our default final concentration of glycerol is 50%. Customers could use it as reference. Storage: The shelf life is related to many factors, storage state, buffer ingredients, storage temperature and the stability of the protein itself. Generally, the shelf life of liquid form is 6 months at -20 °C/-80 °C. The shelf life of lyophilized form is 12 months at -20 °C/-80 °C. Notes: Repeated freezing and thawing is not recommended. Store working aliquots at 4 °C for up to one week. Relevance: Human Interleukin 15 (IL-15) is a cytokine that regulates T cell and natural killer cell activation and proliferation. IL-15 binds to the alpha subunit of the IL15 receptor (IL-15RA) with high affinity. IL-15 also binds to the beta and gamma chains of the IL-2 receptor, but not the alpha subunit of the IL2 receptor. IL-15 is structurally and functionally related to IL-2. Both cytokines share some subunits of receptors, allowing them to compete for and negatively regulate each other's activity. The number of CD8+ memory T cells is controlled by a balance between IL-15 and IL-2. Despite their many overlapping functional properties, IL-2 and IL-15 are, in fact, quite distinct players in the immune system. IL-15 is constitutively expressed by a wide variety of cell types and tissues, including monocytes, macrophages and DCs. Mature Human IL-15 shares 70% amino acid sequence identity with Mouse and Rat IL-15. Reference: n/a. Function: Cytokine that stimulates the proliferation of T-lymphocytes. Stimulation by IL-15 requires interaction of IL-15 with components of IL-2R, including IL-2R beta and probably IL-2R gamma but not IL-2R alpha.