Rat Interleukin-18 (Recombinant)

Recombinant Rat Interleukin-18

Source: E.Coli

Background: Interleukin-18 is a member of the interleukin-1 family of cytokines with pro-inflammatory and tumor-suppressive properties. Its ability to potently enhance the production of interferon-gamma indicates in particular the crucial function of interleukin-18 as an immunomodulatory molecule. In fact, high levels of interleukin-18 are detected in human diseases associated with immunoactivation including viral or bacterial infections and chronic inflammation. Animal models suggest suppression of interleukin-18 bioactivity as a novel therapeutic concept specifically for the treatment of chronic inflammatory diseases such as rheumatoid arthritis, Crohn\\\'s disease, and psoriasis. It is the only cytokine with a unique capacity to induce T helper 1 or T helper 2 polarization, depending on the immunologic context.

Description: Recombinant Rat IL-18 produced in E.Coli is a single, non-glycosylated polypeptide chain containing 158 amino acids and having a molecular mass of 18260 Dalton. Recombinant Rat Interleukin-18 is purified by proprietary chromatographic techniques.

Physical Appearance: Sterile Filtered White lyophilized (freeze-dried) powder.

Formulation: Lyophilized from a concentrated (1mg/ml) solution in water containing 0.4 x PBS pH=7.2.

Solubility: It is recommended to reconstitute the lyophilized IL-18 in sterile 18MO-cm H2O not less than 100 g/ml, which can then be further diluted to other aqueous solutions.

Stability: Lyophilized Interlekin-18 although stable at room temperature for 3 weeks, should be stored desiccated below -180C. Upon reconstitution IL-18 should be stored at 40C between 2-7 days and for future use below -180C. For long term storage it is recommended to add a carrier protein (0.1% HSA or BSA). Please avoid freeze-thaw cycles.

Purity: Greater than 95.0% as determined by: (a) Analysis by RP-HPLC. (b) Anion-exchange FPLC. (c) Analysis by reducing and non-reducing SDS-PAGE Silver Stained gel.

Amino acid sequence: The sequence of the first five N-terminal amino acids was determined and was found to be His-Phe-Gly-Arg-Leu.

Dimers and aggregates: Less than 1% as determined by silver-stained SDS-PAGE gel analysis.

Biological Activity: ProSpec\\\'s Rat IL-18 is fully biologically active when compared to standard. The ED50 as determined by the dose-dependant stimulation of IFN-gamma by murine lymph node cells (4 x 105 cells/well) co-stimulated with sub optimal dose of ConA (0.75ug/ml) is 12 ng/ml. The medium was RPMI containing 10% FCS and 50 M 2-ME.

Endotoxin: Less than 0.1 ng/ g (IEU/ g) of rat IL-18.

Protein content: Protein quantitation was carried out by two independent methods: 1. UV spectroscopy at 280 nm using the absorbency value of 0.213 as the extinction coefficient for a 0.1% (1mg/ml) solution. This value is calculated by the PC GENE computer analysis program of protein sequences (IntelliGenetics). 2. Analysis by RP-HPLC, using a standard solution of IL-18 as a Reference Standard.

Usage: BioWORLD\\\'s products are furnished for LABORATORY RESEARCH USE ONLY. The product may not be used as drugs, agricultural or pesticidal products, food additives or household chemicals.