Interferon beta 1 (IFNb1, beta 1b,IFNb1b), human recombinant (rHuIFNb1)

One of the type I interferons produced by fibroblasts in response to stimulation by live or inactivated virus or by double-stranded RNA. It is a cytokine with antiviral, antiproliferative, and immunomodulating activity. The synthesis of IFN-beta can be induced by common inducers of interferons, including viruses, double-stranded RNA, and micro-organisms. It is induced also by some cytokines such as TNF and IL-1. Recombinant Human IFN-beta 1b is a single, non-glycosylated mutein (variant form) of human Interferon beta-1b polypeptide chain containing 165 amino acids and having a molecular mass of 18.5kD. The Interferon beta gene was cloned from human fibroblasts and altered to substitute Serine for the Cysteine residue found at position 17. , Amino Acid Sequence:, The sequence of the first five N-terminal amino acids was determined and was found to be Ser-Tyr-Asn-Leu-Leu. Biological Activity: Interferon beta-1b is fully biologically active when compared to standard. The specific activity as determined in a viral resistance assay (human "Wish" cell line and VSV virus or the monkey VERO cell line with EMCV virus) was found to be 32x10e6IU/mg. Protein Content: Protein quantitation was carried out by two independent methods: , 1. UV spectroscopy at 280nm using the absorbency value of 1.493 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 calibrated solution of IFN-beta as a Reference Standard. Storage and Stability: Lyophilized powder may be stored at -20°C. Stable for 12 months after receipt at -20°C. Reconstitute with sterile ddH2O. Aliquot to avoid repeated freezing and thawing. Store at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.