| Species : | Human | 
                                
                                    | Source : | E.coli | 
                                
                                    | Protein Length : | 153 | 
                                
                                    | Description : | Interleukin-1 receptor antagonist (IL-1ra) is a member of the IL-1 family. Endogenous IL-1ra is produced in numerous animal disease models as well as in human autoimmune and chronic inflammatory diseases. It binds to IL-1 receptors in competition with IL-1, but does not elicit intracellular response from this binding. Its role in counteracting the proinflammatory effects of IL-1 is being studied by numerous research groups. IL-4 and IL-13 have been shown to amplify the stimulatory effect of IL1-beta on the production of soluble and intracellular forms of IL1-ra.The regulated expression of IL1ra in various cell types has been shown to be influenced by cytokines. In synovial fibroblasts the synthesis of IL-1ra is markedly enhanced by IL-1, TNF-alpha, or PDGF. | 
                                
                                    | Form : | Sterile Filtered White lyophilized (freeze-dried) powder. | 
                                
                                    | Bio-activity : | Fully biologically active when compared to standard. The ED50 as determined by the dose-dependant inhibition of IL-1 stimulation of D10S cells was found to be 0.5 ng/mL, corresponding to a Specific Activity of >2.0 × 10^6 IU/mg. | 
                                
                                    | Molecular Mass : | Approximately 17.0 kDa, a single non-glycosylated polypeptide chain containing 153 amino acids. | 
                                
                                    | AA Sequence : | MRPSGRKSSKMQAFRIWDVNQKTFYLRNNQLVAGYLQGPNVNLEEKIDVVPIEPHALFLGIHGGKMCLSCVKSGDETRLQLEAVNITDLSENRKQDKRFAFIRSDSGPTTSFESAACPGWFLCTAMEADQPVSLTNMPDEGVMVTKFYFQEDE | 
                                
                                    | Endotoxin : | Less than 1 EU/μg of rHuIL-1ra as determined by LAL method. | 
                                
                                    | Purity : | >95% by SDS-PAGE and HPLC analyses. | 
                                
                                    | Storage : | This lyophilized preparation is stable at 2-8 centigrade, but should be kept at -20 centigrade for long term storage, preferably desiccated. Upon reconstitution, the preparation is stable for up to one week at 2-8 centigrade. For maximal stability, apportion the reconstituted preparation into working aliquots and store at -20 to -70 centigrade. Avoid repeated freeze/thaw cycles. | 
                                
                                    | Storage Buffer : | 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 < -20C. Further dilutions should be made in appropriate buffered solutions. |