Invitrogen™ Mouse IL-12 p70

Description

Interleukin-12 (IL-12) is a heterodimeric 70 kDa cytokine composed of two covalently linked, glycosylated chains with molecular weights of 40kD (p40) and 35-kD (p35). IL-12 is mainly produced by monocytes, macrophages, and dendritic cells in response to bacterial products such as lipopolysaccharides (LPS), to intracellular pathogens or upon interaction with activated T cells. IL-12 was originally discovered because of its ability to induce interferon-gamma (IFN-g) production, cell proliferation, and cytotoxicity mediated by natural killer cells and T cells. Studies have established that IL-12 also plays a key role in the development of Th1 responses, leading to IFN-g and IL-2 production. These cytokines can in turn promote T-cell responses and macrophage activation. Recombinant mouse IL-12 p70 is produced in baculovirus-infected insect cells as an authentic heterodimer of precursor p35 and p40 subunits using a dual promoter expression system. IL-12 p70 is distinct from other available forms of the protein in that it is expressed as a true heterodimer, as opposed to a single-chain, pseudo-heterodimer in which the subunits are joined by an artificial linker. The responses of lymphocytes to this cytokine are mediated by the activator of transcription protein STAT4. Nitric oxide synthase 2A (NOS2A/NOS2) is found to be required for the signaling process of this cytokine in innate immunity. Human and mouse IL-12 p40 share about 70% amino acid sequence homology. Description: Interleukin-12 (IL-12) is a heterodimeric 70 kD (p70) cytokine composed of two covalently linked, glycosylated chains, 40kD (p40) and 35-kD (p35). IL-12 is mainly produced by monocytes, macrophages, and dendritic cells in response to bacterial products such as lipopolysaccharides (LPS), to intracellular pathogens or upon interaction with activated T cells. IL-12 was originally discovered because of its ability to induce interferon-gamma (IFN-g) production, cell proliferation, and cytotoxicity mediated by natural killer cells and T cells. It is now established that IL-12 also plays a key role in the development of Th1 responses, leading to IFN-g and IL-2 production. These cytokines can in turn promote T-cell responses and macrophage activation. eBioscience′s recombinant mouse IL-12 p70 is produced in baculovirus-infected insect cells as an authentic heterodimer of precursor p35 and p40 subunits using a dual promoter expression system. It is distinct from other available forms of the protein in that it is expressed as a true heterodimer, as opposed to a single-chain, pseudo-heterodimer in which the subunits are joined by an artificial linker. Applications Reported: Recombinant mouse IL-12 is biologically active and can be used as a standard for p40 or p70 ELISA. Applications Tested: The ED50 of this protein, as measured by IFN gamma induction assay in mouse splenocytes, is less than or equal to 175 pg/mL. This corresponds to a specific activity of greater than or equal to 5.7 x 10e6 Units/mg. Source: Insect cells infected with baculovirus: mouse p40, amino acids met 1-Ser 335, accession &Num; NM_008352 was co-expressed with mouse p35, amino acids met 1-Ala 215, accession &Num; NM_008351. Bioactivity: The ED50 of this protein, as measured by IFN gamma induction assay in mouse splenocytes, is less than or equal to 175 pg/mL. This corresponds to a specific activity of greater than or equal to 5.7 x 10e6 Units/mg. Endotoxin: Less than 0.01ng/ug cytokine as determined by the LAL assay. Purity: >98% as determined by SDS-PAGE. Molecular Weight: The heterodimeric, p40, amino acids met 23-ser 335, cystine linked to p35, amino acids arg 23-ala 215, has a predicted molecular mass of 57,496. On non-reducing SDS-PAGE the heterodimeric cystine-linked protein migrates as a 65 kDa protein. The DTT reduced protein migrates as 43 kDa and 24 kDa polypeptides. Storage and handling: For best recovery, quick-spin vial prior to opening. Use in a sterile environment. Purity: Greater than 98%, as determined by SDS-PAGE. Aggregation: Less than 10%, as determined by HPLC. Filtration: 0.2μm post-manufacturing filtered.