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, IFN-α is an acid-stable molecule that signals through IFN-α/βR, which is also used by IFN-β. Both IFNs have similar anti-viral activity and regulate expression of MHC class I antigens. IFN-α contains four highly conserved cysteine residues that form two disulfide bonds, one of which is necessary for biological activity. PeproTech’s Recombinant Human IFN-β is a 20.0 kDa protein containing 166 amino acid residues. Due to glycosylation, IFN-β has an approximate MW of 22.3 kDa based on SDS-PAGE gel and Mass Spectrometry.
Amino Acid Sequence
Chinese Hamster Ovary Cells (CHO)
Assay #1:Measured by its ability to induce apoptosis in HeLa cells. The expected ED 50 for this effect is 20–30 ng/ml. Assay #2: Determined by its ability to stimulate the proliferation of human TF-1 cells. The expected ED 50 is ≤ 0.1 ng/ml, corresponding to a specific activity of ≥ 1×10 7 units/mg.
Endotoxin level is <0.1 ng/μg of protein (<1EU/μg).
Centrifuge the vial prior to opening. Reconstitute in water to a concentration of 1.0 mg/ml. Do not vortex. This solution can be stored at 2–8°C for up to 1 week. For extended storage, it is recommended to further dilute in a buffer containing a carrier protein (example 0.1% BSA) and store in working aliquots at –20°C to –80°C.