IL-1ra was originally isolated from the urine of patients with monocytic leukemia and has also been purified from adherent monocytes. The naturally occurring, fully glycosylated form has an apparent molecular weight of about 25,000 Daltons. The protein shows 26% amino acid homology to IL-1 beta and 19% homology to IL-1 alpha. It will compete with either factor for receptor binding, but does not interact with either one. Human IL-1ra will bind to both types of IL-1 receptor (I and II) on human cells, but reportedly will not block binding to the type II receptor on murine pre-B cell lines. The recombinant, non-glycosylated form of IL-1ra blocks binding of IL-1 to its receptor equally as well as the naturally-occurring, glycosylated form. The IL-1ra has been shown to block the inflammatory responses induced by IL-1 both in vitro and in vivo. Currently, pre-clinical and clinical studies are underway to test possible therapeutic applications for IL-1ra in the treatment of sepsis, rheumatoid arthritis and chronic myelogenous leukemia. Product Properties Synonyms IL-1RN, IRAP Accession P18510 GeneID 3557 Source E.coli-derived Human IL-1RA, Arg26-Glu177. Molecular Weight Approximately 26.2 kDa. AA Sequence RPSGRKSSKM QAFRIWDVNQ KTFYLRNNQL VAGYLQGPNV NLEEKIDVVP IEPHALFLGI HGGKMCLSCV KSGDETRLQL EAVNITDLSE NRKQDKRFAF IRSDSGPTTS FESAACPGWF LCTAMEADQP VSLTNMPDEG VMVTKFYFQE DE Tag None Physical Appearance Sterile Filtered White lyophilized (freeze-dried) powder. Purity > 96% by SDS-PAGE and HPLC analyses. Biological Activity The ED50 as determined by inhibiting IL-1α-dependent proliferation of murine D10S cells is less than 40 ng/mL, corresponding to a specific activity of > 2.5 × 104 IU/mg in the presence of 50 pg/ml rHuIL-1α. Fully biologically active when compared to standard. Endotoxin < 1.0 EU per 1μg of the protein by the LAL method. Formulation Lyophilized from a 0.2 µm filtered concentrated solution in PBS, pH 7.4. Reconstitution We recommend that this vial be briefly centrifuged prior to opening to bring the contents to the bottom. Reconstitute in sterile distilled water or aqueous buffer containing 0.1% BSA to a concentration of 0.1-1.0 mg/mL. Stock solutions should be apportioned into working aliquots and stored at ≤ -20°C. Further dilutions should be made in appropriate buffered solutions. Shipping and Storage The products are shipped with ice pack and can be stored at -20℃ to -80℃ for 1 year. Recommend to aliquot the protein into smaller quantities when first used and avoid repeated freeze-thaw cycles. Cautions 1. Avoid repeated freeze-thaw cycles. 2. For your safety and health, please wear lab coats and disposable gloves for operation. 3. For research use only!
