Proteins of this family play an important role in inducing non-specific resistance against a broad range of viral infections. They also affect cell proliferation and modulate immune responses. Produced by peripheral blood leukocytes and lymphoblastoid cells, IFNalpha is an acid stable molecule that signals through IFNalpha/betaR, which is also used by IFNbeta. Both IFNs have similar anti-viral activity and regulate expression of MHC class I antigens. IFNalpha contains four highly conserved cysteine residues which form two disulfide bonds, one of which is necessary for biological activity. Recombinant human IFNbeta is an 20kD protein containing 166aa. Due to glycosylation, IFNbeta has an approximate MW of 22.3kD based on SDS-PAGE gel and Mass Spectrometry. Recombinant protein corrresponding to human IFNB1, expressed in CHO cells. Biological Activity: Determined by a cytotoxicity assay using human TF-1 cells. The expected ED50 is 0.1ng/ml, corresponding to a specific activity of 1x10e7 units/mg. Amino Acid Sequence: MSYNLLGFLQ RSSNFQCQKL LWQLNGRLEY CLKDRMNFDI PEEIKQLQQF QKEDAALTIY EMLQNIFAIF RQDSSSTGWN ETIVENLLAN VYHQINHLKT VLEEKLEKED FTRGKLMSSL HLKRYYGRIL HYLKAKEYSH CAWTIVRVEI LRNFYFINRL TGYLRN Storage and Stability: Lyophilized and reconstituted products are stable for 6 months after receipt at -20C. Reconstitute with sterile ddH2O. For long term storage it is recommended to add a carrier protein (0.1% HSA or BSA). Aliquot to avoid repeated freezing and thawing. Store at -20C. 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.
